Neuroendoscopic Lavage: a single-center retrospective cohort in in the United States

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We describe an initial uni-center series from the United States. Methods Retrospective review was performed for premature infants with IVH that underwent NEL at our institution between 2020–2023. Patient characteristics, clinical variables, and radiological assessments were collected. Results Eleven patients (five female) with IVH grade III/IV underwent 13 procedures. Mean gestational age (GA) was 25 weeks and two days. Mean birth weight (BW) was 0.83 kilograms (kg). Average age at NEL was 40.4 ± 21.5 days, mean weight was 1.51 ± 0.3 kg. Mean frontal horn index decreased from 0.68 to 0.56 after NEL (p < 0.001). Cerebrospinal fluid infection was diagnosed in 18.2%, secondary hemorrhage in 18.2%, seizures in 27.3% of patients. One patient died postoperatively with refractory coagulopathy. Conversion to ventriculoperitoneal shunt at six-month follow up was 8/11 (72.7%), with 50% one-year revision-free shunt survival. No patients required a multi-catheter system. Rates of comorbidities and shunt dependency showed very strong positive correlations, hyaline membrane disease rate (R 2 = 0.950), necrotizing enterocolitis (R 2 = 0.999) and persistent ductus arteriosus (R 2 = 0.975). Prematurity and shunt dependency showed a moderate to strong negative correlation, GA (R 2 = 0.527) and BW (R 2 = 0.344). Conclusion Extreme prematurity and comorbidities are associated with increased shunt dependency. However, NEL may decrease the development of complex multi-lobulated hydrocephalus and the need for future shunt revisions. Larger, long-term studies are needed to define optimal timing and criteria for NEL and its benefits and impact on neurodevelopment in this fragile population. Intraventricular Hemorrhage Posthemorrhagic hydrocephalus prematurity ventriculosubgaleal shunt Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Intraventricular hemorrhage (IVH) is a serious complication of prematurity, impacting 20–40% of premature births weighing < 1.5 kilograms (kg) worldwide [ 1 ]. Risk of severe IVH is inversely associated with infant maturity, as represented by gestational age (GA) and birth weight (BW), with mortality rates up to 40% [ 2 ]. Several factors contribute to the morbidity and mortality of severe IVH including injury from the primary hemorrhage and secondary complications. Of patients with IVH, 25–50% of infants < 1500 g will develop posthemorrhagic hydrocephalus (PHH) requiring neurosurgical intervention [ 3 – 5 ]. IVH may elevate concentrations of transforming growth factor-β (TGF-β) and other cytokines potentially exacerbating cerebral damage and neuroinflammation [ 6 , 7 ]. Neurosurgical treatments for IVH include ventriculosubgaleal shunts (VSGS), lumbar punctures, ventricular aspiration, and ventricular access devices (VAD) [ 8 ]. Despite multiple studies and guidelines there is no treatment consensus [ 9 ]. Drainage, irrigation, and fibrinolytic therapy (DRIFT) was a randomized controlled trial that, despite early discontinuation due to hemorrhage-associated morbidity, did show decreased shunt dependency compared with standard treatment through ten year follow up [ 7 , 8 ]. Neuroendoscopic lavage (NEL), guided by the DRIFT framework, enables early IVH blood products via controlled endoscopy, with lower rebleed rates, favorable outcomes in multiple European cohorts, and level III CNS guideline support [ 9 – 16 ]. Despite multiple European studies, there is a paucity of studies from North America. A recent study conducted in the United States (US) reported an initial favorable experience with NEL [ 17 ]. Variations in neonatal populations and practices between the US and Europe may reveal cohort differences impacting IVH severity and outcomes. We report our initial experience with NEL in a US cohort of patients with IVH of prematurity and PHH. Methods Patient Selection All very preterm neonates (<32 weeks) with IVH of prematurity and PHH who underwent NEL at our institution from 2020-2023 with a minimum eighteen month follow up were included for retrospective chart review. Indications for neurosurgical evaluation were based on our modification of the Hydrocephalus Clinical Research Network (HCRN) clinical care pathway [18]. Each surgical intervention was based on multidisciplinary neonatology/neurosurgery collaboration (Figure 1) . Patients with grade I/II IVH hemodynamic instability, and/or uncorrectable coagulopathy were excluded from NEL. This study was approved by our Institutional Review Board (IRB#2023-6158). Endoscopes Flexible (Storz, Tuttlingen, Germany) and rigid endoscopes (Minop Rigid [Aesculap, Tuttlingen, Germany] Lotta and Little Lotta [Storz, Tuttlingen, Germany]) are used, as determined by surgeon preference and equipment availability ( Figure 2) . NEL procedure Under general anesthesia, patients were placed supine with their head turned 90 degrees lateral, approach side facing up, on a DORO (Pro Med Instruments GmbH, Freiburg, Germany) headholder system. Thorough plastic draping kept the infant’s body warm and dry during procedural irrigation. Weight-based dosing of antibiotics were given within one hour of skin incision. The frontal incision was made two centimeters off midline, anterior to the coronal suture, and lateral to the anterior fontanelle. The endoscope was inserted into the lateral ventricle with or without ultrasound guidance. Once bloody or hemosiderin-laden cerebrospinal fluid (CSF) is encountered, warm normal saline irrigation is initiated to assist with visualization of expected anatomic landmarks for orientation. Blood products are removed via the endoscope working portal by applying gentle manual syringe suction proximally. Septostomy allowed access to the contralateral ventricle to repeat this process. Warm irrigation was continued until it ran clear. Following endoscope removal, the VSGS intraventricular catheter was placed through the same burr hole, while the tapping reservoir, and patent opening distal to the reservoir to allow for CSF egress were placed in the subgaleal space (Figure 3). Multidisciplinary management is essential for postoperative care following NEL. Screening video electroencephalography (vEEG) was part of our clinical pathway to avoid over- or under-treatment with anti-epileptics. Additional seizure medications were given for clinical seizures or EEG changes. Head ultrasound (HUS) was followed at least weekly with de-escalation over time if the patient’s neurologic exam remained stable. If clinical or radiographic signs of hydrocephalus recurred, additional CSF diversion procedures were considered including repeat NEL, VSGS revision, endoscopic third ventriculostomy (ETV) with or without lysis of adhesions, and/or placement of shunt. Continued bedside temporization for infants <2kg most commonly involved VSGS reservoir taps. Patient Factors Patient risk factors such as GA, BW, pre-operative modified Papile grade, and comorbid conditions were reviewed. Comorbid conditions included hyaline membrane disease (HMD), persistent ductus arteriosus (PDA), necrotizing enterocolitis (NEC), meningitis (suspected or proven), and seizures. Perioperative Events Perioperative events included CSF infection (defined by positive CSF cultures), secondary hemorrhage (defined by new/increased blood volume on imaging within 72 hours following surgery), and postoperative subclinical electrographic seizures (defined by detection on routine screening vEEG by the neonatal neurology team). Radiographic Assessment and Analysis IVH severity was described using the modified Papile classification [19]. Grading was performed by pediatric neuroradiologists, or if unavailable, the study team. Frontal occipital horn ratio (FOHR) and ventricular index (VI) were measured from the most recent preoperative HUS (within 72 hours) of NEL and first postoperative HUS. FOHR is defined as the sum of the frontal horn width and the occipital horn width divided by two times the biparietal diameter. VI is the distance between the lateral wall of the anterior horn and the falx (Supplementary figure 1). Ventriculoperitoneal shunt (VPS) Decision for VPS placement after NEL+VAD/VSGS was based on surgeon assessment. Shunt revisions were recorded for patients who received a VPS. Statistical Analysis Delta was calculated by subtracting the preoperative measurement of VI and FOHR from the postoperative values, respectively. A paired, one-tailed Student’s T-test was used to compare pre-and post-operative FOHR and VI. P≤0.05 was considered significant. Linear regression was performed with mean prematurity and comorbidities as independent variables and mean shunt dependency rate as a dependent variable. R 2 values were interpreted using the following determinations: very strong (0.7-1.0), strong (0.4-0.69), moderate (0.3-0.39), and weak (0.2-0.29). Statistical analysis was completed using RStudio (RStudio Team, 2023). Studies were included in the linear regression if mean values for shunt dependency were independently reported for an NEL only group. Results Patient Characteristics Eleven infants (five female), with BW <1.5 kg underwent NEL+VSGS/VAD between June 2020 and September 2023. In our cohort, 2/11 patients (18.2%) had grade III IVH, 9/11 (81.2) had grade IV IVH. The mean FOHR was 0.51 ±.08 at time of consultation. All patients showed clinical and imaging findings of worsening ventriculomegaly meeting criteria for CSF diversion via temporizing measure ( Figure 1 ). Patient demographics are described in Table 1 . Table 1. Demographics and Surgery Characteristics Case no. GA, sex BW/ Weight at Sx (g) DOL at Sx Endoscope Temporizing Device Operative Time (mins) LOS Follow-up (days) 1 24w4d, M 0.89 / 1.68 47 Flexible Storz VSGS 92 258 1104 2 24w2d, F 0.75 / 1.51 40 Flexible Storz VSGS 113 289 1223 3 23w0d, F 0.61/ 0.81 28 Flexible Storz VSGS 43 140 873 4 24w0d, F 0.60 / 1.59 46 Minop Rigid VSGS 61 68 737 5 25w1d, M 0.72 / 1.71 53 Lotta Rigid VSGS 65 54 54 6 25w3d, M 0.83/ 1.65 57 Minop Rigid VAD 71 217 522 7 25w5d, M 0.65 / 1.54 41 Minop Rigid VSGS 49 146 475 8 27w5d, M 1.18 / 1.24 15 Little Lotta Rigid VSGS 105 34 364 9 27w2d, F 1.07 / 1.26 18 Lotta Rigid VAD 62 166 281 10 27w0d, F 1.10 / 1.04 14 Little Lotta Rigid VSGS 41 202 215 11 24w0d, M 0.74 / 2.58 84 Flexible Storz VSGS 41 221 184 GA, Gestational Age; M, male, F, Female; BW, birth weight Sx, surgery; IVH, intraventricular hemorrhage; DOL, day of life; kg, gram; w, weeks; d, days; VSGS, Ventriculosubgaleal shunt; VAD, Ventricular access device; LOS, length of stay The cohort self-identified as White (5/11, 45.5%), Black (2/11, 18.2%), Asian (1/11, 9.1%), and Other (3/11, 27.3%). Hispanic/Latino was the reported ethnicity in 3/11 patient families (27.3%). Mean gestational age at birth was 25 weeks and 2 days ± 1.5 weeks. Average BW was 0.83kg (range 0.6-1.1kg). Comorbidities in this cohort included HMD in all cases, PDA in 10/11 (90.9%), NEC in 8/11 (72.3%), and meningitis in 2/11 (18.2%). Seizures were diagnosed by vEEG in 5/11 (45.5%) of the patients, with two patient seizures occurring only in the preoperative period. Prior to neurosurgical intervention, seven patients had coagulopathies and cytopenias necessitating blood product transfusions and six patients required vasopressors to maintain normotension. The average length of stay in the neonatal intensive care unit (NICU) was 158±83 days. The mean in-hospital ventilation duration was 70.3 days (range 2-279 days). At discharge 5/10 were on room air, 3/10 required nasal canula with supplemental oxygen, and 2/10 were ventilator-dependent with a tracheostomy. Nutrition status at discharge included 1/10 taking oral feeds, 4/10 requiring a nasogastric tube, and 5/10 with a gastrostomy tube. The mean total follow-up was 29.5 months (range 1.8-52.7 months). Perioperative variables Average age at time of NEL was 40.4±21.5 days and mean weight was 1.51±0.3 kg. One patient received an NEL at 2.6 kg due to prior bowel perforation and expected future abdominal surgeries, despite meeting VPS criteria. Mean operative time was 67.5±26 minutes. Mean estimated blood loss was 1.5±0.6 milliliters (Table 1). The Storz flexible endoscope was used in four patients, the MINOP Rigid endoscope in three patients, the Lotta Rigid in two patients, and the Little Lotta Rigid in two patients. Two patients received blood product transfusions and one patient required vasopressors perioperatively. Perioperative events Outcomes and perioperative events are shown in Table 2 . Table 2. Outcomes Case # FOHR ∆ VI (mm >97 th ) ∆ Operative Time (mins) Perioperative events Clot Burden Remaining Permanent CSF diversion 1 -0.10 -8.30 92 preop seizure Yes yes 2 -0.26 -9.10 113 preop seizure, CSF infection * yes 3 -0.14 -10.05 43 Local skin Infection No no 4 -0.06 -4.85 61 Wound dehiscence * yes 5 -0.05 0.80 65 Hemorrhage, Death Yes no 6 -0.24 -12.10 71 none * yes 7 -0.08 -7.00 49 preop seizure, vEEG seizure POD 1 Yes yes 8 -0.11 -4.25 105 CSF infection Yes yes 9 -0.11 -3.00 62 vEEG seizure POD 3 Yes yes 10 -0.06 2.60 41 none * yes 11 -0.08 -6.30 41 vEEG seizure POD2, hemorrhage No No ∆ represents the change in preoperative and postoperative FOHR or VI , *data was unavailiable, #, Number; FOHR, frontal-occipital horn ratio; VI, ventricular index; LOS, length of stay; CSF, cerebrospinal fluid; vEEG, video EEG; POD, post-op day There was one mortality in a patient with grade IV IVH, multiple comorbidities and redirection of goals of care. This patient was excluded from perioperative adverse event frequency calculations. CSF infection in the postoperative period was diagnosed in two patients, one with enterobacter cloacae, another with methicillin sensitive staphylococcus aureus. Two patients had secondary IVH within two days post-operatively. Four (36.4%) patients required repeat temporizing measures (all with re-do VSGS; two with and two without NEL) before definitive CSF diversion as they had hostile distal CSF shunting sites or low body weight. Three (27.3%) patients had vEEG evidence of a seizure within 72 hours postoperatively. Radiographic measurements Cranial imaging in the form of a HUS was obtained postoperatively (mean = four days, range 0-10 days). The mean FOHR decreased from 0.68 prior to NEL to 0.56 after NEL (∆ -0.12, p97 th percentile decreased from 11.8 mm prior to NEL to 6.2 mm after NEL (∆ -5.6, p<0.001). Following NEL all IVH grades were stable or improved: one patient had grade 0, three patients had grade I, three had grade II, one had grade III, an four had grade IV IVH. Permanent CSF diversion Patients had an average follow-up of 30 months. Eight patients thus far have required permanent CSF diversion. Seven patients had a VPS placed and one had a ventriculoatrial shunt placed given a hostile abdomen. Mean time between NEL and shunt insertion time was 149 days. Mean age at shunt insertion was 6.1±5.6 months and the mean weight was 3.87±1.8 kg. The mean number of revisions was 1.6. Four patients required at least one revision at 23, 28, 119 and 120 days. The remaining four patients have not required shunt revisions (mean 33±10.4 months). Revision free shunt-survival at one year was 50%. The Kaplan-Meier curve for revision free shunt-survival is shown in Supplementary Figure 2 . Four of eleven patients developed multiloculated hydrocephalus. Neuroendoscopic fenestration enabled all cases to be successfully managed by a single ventricular catheter. Compared with most European cohorts our patients demonstrated higher shunt dependency rates ( Table 3 ). Table 3. Comparison with published cohorts Lurie Schulz, 2014 D’Arcangues, 2018 Tirado-Caballero, 2020 Frassanito 2021 Honeyman, 2022 Flanders, 2025 N= 11 19 56 46 24 26 12^ GA at Birth 25w2d 27w6d 27w6d 30w1d 28w5d 29w4d 25w0d Birth Weight (kg) 0.83 1.04 1.11 1.67 1.31 1.41 0.78 IVH Grade II 0 (0.0%) 2 (10.5%) 5 (8.9%) 0 (0.0%) * 1 (3.8%) 0 III 2 (18.2%) 13 (68.4%) 23 (41.1%) 28 (60.1%) * 8 (3.1%) * IV 9 (81.2%) 3(15.8%) 28 (50.0%) 18 (39.1%) * 17 (65.4%) * Comorbid Conditions HMD 11 (100%) * * 22 (47.8%) * 18 (69.2%) * NEC 8 (72.3%) * * 5 (10.9%) * 11 (42.3%) * PDA 10 (90.9%) * * 11 (23.9%) * 17 (65.3%) * PMA at NEL 30.86w 31.71w 31.28w * 32.7w 39.6w 29.82w Weight at NEL (g) 1.51 1.45 1.52 * * * 1.29 Perioperative Events CSF Infection 2 (18.2%) 2 (10.5%) 2 (3.6%) 10 (21.7%) 1 (4.2%) 2 (7.7%) 1 (8.3%) Re-bleed 2 (18.2%) * 5 (8.9%) 3 (6.52%) * 1 (3.8%) 1 (8.3%) Death 1 (9.1%) * 3 (5.4%) 3 (6.52%) 1 (4.2%) 0 (0.0%) 1 (8.3%) Permanent CSF diversion 72.7% 58.0% 56.6% 58.7% 87% 5.4% 72.7% Time to Shunt (w) 10.4 6.0 6.02 * 4.6 10.14 10 1-year Shunt Survival 50% * 63.6% 50% * 64.7% * Median # of Procedures 2 2 2 * * * * *data was not available ; ^Flanders et al. Only reported demographic information for 11 patients; #, number Linear regression between comorbidities and shunt dependency were performed using patient-level values reported in Tirado-Caballero et al. and Honeyman et al [13, 14].There was a very strong positive correlation between HMD rate (R 2 =0.950), NEC (R 2 =0.999) and PDA (R 2 =0.975) and shunt dependency ( Figure 4 ). Linear regression between prematurity was performed using data from five published cohorts [10, 12–14, 17]. There was a strong negative correlation between gestational age and shunt dependency, GA (R 2 =0.527) and moderate negative correlation between BW and shunt dependency (R 2 =0.344, Figure 5 ). Discussion This retrospective cohort study describes a single-center US experience with NEL. This US cohort is similar in average GA (25 weeks and 2 days) and BW (0.87 kg) to one published in another US institution (average GA 25 weeks, BW 0.78 kg) [ 17 ]. Prior studies have shown the incidence of IVH is significantly higher in North American compared to European cohorts (p-value < 0.001), and that the incidence proportion of severe IVH for GA 25–27 weeks is higher in North America as well (North America: 0.22, Europe 0.16) [ 20 ]. When compared with European cohorts, our patients are more premature with greater medical comorbidities. These differences may reflect variations in neonatal populations and practices between the US and Europe. [ 21 ]. Comorbid conditions in our cohort included higher rates of HMD, bronchopulmonary dysplasia, PDA, and NEC, which corresponds with 55% of our patients being discharged on respiratory support and 91% with nutritional support with tube feeds. Our cohort also had longer average mechanical ventilation duration (70.3 days) versus four days in D’Arcangues et al cohort [ 12 ]. Complication rates in this study are similar to previous NEL cohorts. Secondary hemorrhage is similar to European cohorts (18.2%), and is lower than in DRIFT (35% [ 22 ]. Screening vEEG detected post-operative seizures in 27.3% of our patients. This modality gives perspective on the incidence of perioperative seizures in these patients: data that has not been previously quantified or explored in published cohorts. It also allows for early seizure detection and timely treatment, which is critical as the number of days with EEG-confirmed seizures has been identified as a potentially modifiable risk factor to developing postnatal epilepsy [ 23 ]. Our observed CSF infection rate was lower than the Spanish cohort and higher than the published UK and German cohorts [ 10 , 12 – 14 ]. In our study, one patient died postoperatively. This mortality rate is consistent with previously published cohorts, reflecting the medical complexity and fragility of these patients, and underscoring the need for multidisciplinary care and ongoing research. A prospective study of the impact of IVH on mortality in very preterm (26–32 weeks GA) and low BW infants (< 1.5 kg) found that patients with grade III/IV IVH were 14 times more likely to die before NICU discharge compared with grade I/II IVH; surgical interventions for IVH were not reported [ 24 ]. In the North America HCRN Shunting Outcomes in Posthemorrhagic Hydrocephalus (SOPHH) study, 12.7% (13 of the premature infants < 1.5kg BW) who underwent a VAD/VSGS died within six months post-operatively [ 18 ]. A 15-year retrospective study from our institution prior to adoption of NEL similarly found a 10% mortality (n = 3) after temporizing measure (VSGS/VAD) for grade III/IV IVH ([ 25 ]. Amongst both the German and Spanish NEL series (n > 45), they each reported three deaths (6.6%) [ 12 , 13 ]. Similarly, Flanders et al. reported one death (8.3%) among their US NEL patients [ 26 ]. Our mortality case had family wishes for redirection of goals of care after encountering refractory coagulopathy, acute anemia, large volume transfusions, and cardiopulmonary arrest. Our rate of permanent CSF diversion was 72.7% compared to published European cohorts of 56-87.9% [ 12 – 15 ]. This rate is lower than shunt dependency rates reported in our prior retrospective study (77.8%) for grade III/IV IVH and other US studies after VAD/VSGS alone (90–95%) [ 3 , 25 , 27 ]. Flanders et al, whose US cohort had similar BW and GA to this cohort, also reported a permanent CSF diversion rate of 72.7% [ 17 ]. Severe prematurity is a significant risk factor for PHH and subsequent need for VP shunt insertion [ 27 , 28 ]. Pooling data from the studies above increased prematurity and medical comorbidities were associated with greater hunt dependency. A learning curve has also been described. Tirado-Caballero et al saw a 72.72% rate of permanent shunting in their first 11 patients; in subsequent epochs in their experience, this rate dropped to < 54% [ 13 ]. A 2020 Italian retrospective study of 63 infants reported an 87.9% rate of permanent CSF diversion when comparing VSGS and VSGS ± NEL for PHH. Shunt dependency may also be influenced by the extent of IVH. Our series only included grade III/IV IVH patients, with 81.2% having grade IV. Grade IV IVH has a 52% increased risk of shunt dependency as compared to grade II IVH, regardless of intervention [ 29 ]. European studies include patients with Grade II IVH; this variability precludes direct comparison. Surgical timing in preterm infants with IVH involves multidisciplinary risk-benefit assessment. While our time-to-intervention from birth to NEL (5.7 weeks) was longer than most European studies (3.95 weeks), it was more similar to the other US cohort (4.82 weeks). Previous studies have demonstrated improved outcomes and reduced shunt rates with earlier intervention [ 29 – 31 ]. Others have suggested ventriculomegaly indices thresholds of FOHR ≥ 0.66, VI ≥ 8.4mm above the 97th percentile prior to CSF diversion [ 30 ]. We noted an increased time from NEL to shunt insertion of 10.4 weeks for those with NEL versus six weeks without NEL in our historical cohort [ 1 , 10 , 25 ]. The differences in GA at birth and comorbidity burden may also influence timing of shunt insertion. Distal shunt site can be challenging in these patients: two had bowel resections with inhospitable abdomens and four had long-term venous catheters terminating in the right atrium. Ventriculopleural shunts are typically not considered in this age range and is further contraindicated by our patients’ respiratory complications of prematurity. Another reported benefit of NEL is the reduction of complex hydrocephalus [ 12 , 15 ]. Previously conventional treatment cohorts report a median of 3.5 shunt revisions [ 10 , 12 ]. Our study had a median of two neurosurgical procedures. While we recognize that secondary shunt failures are multifactorial and not always preventable, our NEL series has had successful avoidance of multi-catheter multiloculated hydrocephalus. Four patients in our series required additional neuroendoscopic fenestration which has been durable thus far, with none requiring multiple catheter systems. Similarly, the one-year revision free shunt survival in this small US cohort of 50% is similar to European cohorts, and it compares to historically reported rates of 44% in European and US cohorts (13–15, 32). Neurodevelopmental outcomes will be discerned at longer term follow up. The Treatment of Post-Hemorrhagic Hydrocephalus (TROPHY) international prospective database seeks to compare various temporizing measures and is expected to yield additional multicenter information on NEL safety, efficacy, and neurodevelopmental outcomes [ 33 ], and has encouraging 6 month follow up results so far.[ 34 ] Limitations include those inherent to single institution retrospective series with small sample size and relatively short follow up as our cohort matures. Neurodevelopmental outcomes at two and five years follow up will be essential. In addition, our center included three neurosurgeons with evolving access to four endoscopes in the timeframe of the study [ 35 ]. D’Arcangues et al. only used rigid endoscopes with inflow/outflow channels, while the ongoing ENLIVEN-UK randomized controlled trial recruiting across 11 UK centers does not prescribe a standard endoscopic choice [ 12 ] [ 36 ]. For each center, experience using neuroendoscopy, development of standardized perioperative protocols, and multidisciplinary collaboration of neonatology, neurology, neurosurgery, and neuroanesthesiology teams are essential. Conclusions This study shares our single US institution’s initial NEL experience for IVH of prematurity and PHH in a group with greater comorbidities and lower mean GA and birth weight compared with published European cohorts. Further studies are necessary to define the risks and benefits of NEL, the criteria for optimal case selection, and the most appropriate outcomes measures, including long-term neurodevelopment. Abbreviations Neuroendoscopic lavage= NEL; intraventricular hemorrhage= IVH; Gestational Age= GA; kilograms= kg; Birth weight= BW; posthemorrhagic hydrocephalus= PHH; ventriculosubgaleal shunts= VSGS; ventricular access devices (VAD); Drainage, irrigation, and fibrinolytic therapy= DRIFT; Hydrocephalus Clinical Research Network =HCRN; cerebrospinal fluid= CSF; video electroencephalography=vEEG; head ultrasound= HUS; endoscopic third ventriculostomy= ETV; hyaline membrane disease=HMD; persistent ductus arteriosus= PDA; necrotizing enterocolitis=NEC; Frontal occipital horn ratio= FOHR; ventricular index=VI; ventriculoperitoneal shunt=VPS; neonatal intensive care unit= NICU; Shunting Outcomes in Posthemorrhagic Hydrocephalus= SOPHH; Treatment of Post-Hemorrhagic Hydrocephalus= TROPHY Declarations Acknowledgements: The authors acknowledge Megan Votoupal for her help with data collection and study coordination as well as Samantha Leon for her help with initial data extraction. Competing interests: The authors have no conflicts of interest or funding sources to disclose. We confirm that we have read the journal’s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines. Ethics approval: This retrospective chart review study involving human participants was in accordance with the ethical standards of the declaration of Helsinki. The Ann & Robert H. Lurie Children’s Hospital of Chicago (LCH) Institutional Review Board approved this study prior to its initiation (IRB: 2023-6158). Consent: Written informed consent was obtained from patients/parents prior to treatment. Data transparency: All relevant data is included in the manuscript body. Author Contributions: Conceptualization: Sunny Abdelmageed, Sandi Lam; Methodology: Sunny Abdelmageed, Jonathan Scoville, Sandi Lam; Data Curation- Sunny Abdelmageed, Lucinda Chiu; Formal analysis and investigation: Sunny Abdelmageed; Writing-original draft preparation: Sunny Abdelmageed, Lucinda Chiu; Writing- review and editing: Sunny Abdelmageed, Lucinda Chiu, Maria Dizon MD, Ulrich- Wilhelm Thomale, Jeffrey S. Raskin, Michael DeCuypere, Sandi Lam Resources: Maria Dizon, Jeffrey S. Raskin, Michael DeCuypere, Sandi Lam; Visualization- Sunny Abdelmageed, Lucinda Chiu, Jonathan Scoville, Ulrich-Wilhem Thomale, Sandi Lam; Supervision: Jeffrey S. Raskin. All authors have read and approved the final version of the manuscript. Sandi Lam is responsible for the overall content of the manuscript and serves as the guarantor. References El-Atawi K (2016) Risk Factors, Diagnosis, and Current Practices in the Management of Intraventricular Hemorrhage in Preterm Infants: A Review. 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J Neurosurg Pediatr Nov 1:8–23. https://doi.org/10.3171/2014.7.PEDS14322 Schulz M, Buhrer C, Pohl-Schickinger A, et al (2014) Neuroendoscopic lavage for the treatment of intraventricular hemorrhage and hydrocephalus in neonates. J Neurosurg Pediatr Jun 13:626–35. https://doi.org/10.3171/2014.2.PEDS13397 Behrens P, Tietze A, Walch E (2020) Neurodevelopmental outcome at 2 years after neuroendoscopic lavage in neonates with posthemorrhagic hydrocephalus. J Neurosurg Pediatr Aug 26:495–503. https://doi.org/10.3171/2020.5.PEDS20211 d’Arcangues C, Schulz M, Buhrer C, et al (2018) Extended Experience with Neuroendoscopic Lavage for Posthemorrhagic Hydrocephalus in Neonates. World Neurosurg Aug 116:e217-e224:. https://doi.org/10.1016/j.wneu.2018.04.169 Tirado-Caballero J, Rivero-Garvia M, Arteaga-Romero F, et al (2020) Neuroendoscopic lavage for the management of posthemorrhagic hydrocephalus in preterm infants: safety, effectivity, and lessons learned. J Neurosurg Pediatr May 26:237–246. https://doi.org/10.3171/2020.2.PEDS2037 Honeyman SI, Boukas A, Jayamohan J, Magdum S (2022) Neuroendoscopic lavage for the management of neonatal post-haemorrhagic hydrocephalus: a retrospective series. Childs Nerv Syst Jan 38:115–121. https://doi.org/10.1007/s00381-021-05373-8 Frassanito P, Serrao F, Gallini F (2021) Ventriculosubgaleal shunt and neuroendoscopic lavage: refining the treatment algorithm of neonatal post-hemorrhagic hydrocephalus. Childs Nerv Syst 37:3531–3540. https://doi.org/10.1007/s00381-021-05216-6 Kandula V, Mohammad LM, Thirunavu V, et al (2022) The role of blood product removal in intraventricular hemorrhage of prematurity: a meta-analysis of the clinical evidence. Childs Nerv Syst 38:239–252. https://doi.org/10.1007/s00381-021-05400-8 Flanders TM, Hwang M, Julian NW, et al (2025) Neuroendoscopic lavage for posthemorrhagic hydrocephalus of prematurity: preliminary results at a single institution in the United States. J Neurosurg Pediatr 35:345–352. https://doi.org/10.3171/2024.10.PEDS24119 Wellons JC, Shannon CN, Holubkov R, et al (2017) Shunting outcomes in posthemorrhagic hydrocephalus: results of a Hydrocephalus Clinical Research Network prospective cohort study. J Neurosurg Pediatr 20:19–29. https://doi.org/10.3171/2017.1.PEDS16496 Papile LA, Burstein J, Burstein R, Koffler H (1978) Incidence and evolution of subependymal and intraventricular hemorrhage: a study of infants with birth weights less than 1,500 gm. J Pediatr Apr 92:529–34. https://doi.org/10.1016/s0022-3476(78)80282-0 Lai GY, Shlobin N, Garcia RM, et al (2022) Global incidence proportion of intraventricular haemorrhage of prematurity: a meta-analysis of studies published 2010-2020. Arch Child Fetal Neonatal Ed 107:513–519. https://doi.org/10.1136/archdischild-2021-322634 Singh J, Fanaroff J, Andrews B (2007) Resuscitation in the “gray zone” of viability: determining physician preferences and predicting infant outcomes. Pediatr Sep 120:519–26. https://doi.org/10.1542/peds.2006-2966 Whitelaw A, Jary S, Kmita G (2010) Randomized trial of drainage, irrigation and fibrinolytic therapy for premature infants with posthemorrhagic ventricular dilatation: developmental outcome at 2 years. Pediatr Apr 125:. https://doi.org/10.1542/peds.2009-1960 Shellhaas RA, Wusthoff CJ, Numis AL, et al (2021) Early-life epilepsy after acute symptomatic neonatal seizures: A prospective multicenter study. Epilepsia 62:1871–1882. https://doi.org/10.1111/epi.16978 Pascal A, Bruyn N, Naulaers G (2023) The Impact of Intraventricular Hemorrhage and Periventricular Leukomalacia on Mortality and Neurodevelopmental Outcome in Very Preterm and Very Low Birthweight Infants: A Prospective Population-based Cohort Study. J Pediatr 262:. https://doi.org/10.1016/j.jpeds.2023.113600 Lai GY, Abdelmageed S, DeRegnier R-AO, et al (2022) Degree of ventriculomegaly predicts school-aged functional outcomes in preterm infants with intraventricular hemorrhage. Pediatr Res 91:1238–1247. https://doi.org/10.1038/s41390-021-01631-2 Flanders TM, Hwang M, Julian NW, et al (2024) Technique and protocol for bedside neuroendoscopic lavage for post-hemorrhagic hydrocephalus: technical note. Childs Nerv Syst ChNS Off J Int Soc Pediatr Neurosurg 41:39. https://doi.org/10.1007/s00381-024-06697-x Bock HC, Feldmann J, Ludwig HC (2018) Early surgical management and long-term surgical outcome for intraventricular hemorrhage-related posthemorrhagic hydrocephalus in shunt-treated premature infants. J Neurosurg Pediatr Jul 22:61–67. https://doi.org/10.3171/2018.1.PEDS17537 Horbar JD, Badger GJ, Carpenter JH (2002) Trends in mortality and morbidity for very low birth weight infants, 1991-1999. Pediatr Jul 110:143–51. https://doi.org/10.1542/peds.110.1.143 Cizmeci MN, Groenendaal F, Liem KD (2020) Randomized Controlled Early versus Late Ventricular Intervention Study in Posthemorrhagic Ventricular Dilatation: Outcome at 2 Years. J Pediatr Nov 226:28–35. https://doi.org/10.1016/j.jpeds.2020.08.014 Lai GY, Chu-Kwan W, Westcott AB, et al (2021) Timing of Temporizing Neurosurgical Treatment in Relation to Shunting and Neurodevelopmental Outcomes in Posthemorrhagic Ventricular Dilatation of Prematurity: A Meta-analysis. J Pediatr 234:54-64 e20. https://doi.org/10.1016/j.jpeds.2021.01.030 Jin MC, Parker JJ, Rodrigues AJ (2022) Development of an integrated risk scale for prediction of shunt placement after neonatal intraventricular hemorrhage. J Neurosurg Pediatr Apr 29:444–453. https://doi.org/10.3171/2021.11.PEDS21390 Simon TD, Whitlock KB, Riva-Cambrin J (2012) Association of intraventricular hemorrhage secondary to prematurity with cerebrospinal fluid shunt surgery in the first year following initial shunt placement. J Neurosurg Pediatr Jan 9:54–63. https://doi.org/10.3171/2011.10.PEDS11307 Thomale U-W, Cinalli G, Kulkarni AV (2019) TROPHY registry study design: a prospective, international multicenter study for the surgical treatment of posthemorrhagic hydrocephalus in neonates. Childs Nerv Syst 2019;35(4):613–619:. https://doi.org/10.1007/s00381-019-04077-4 Thomale UW, Lukoschus FN, Pennacchietti V, et al (2025) Treatment of posthemorrhagic hydrocephalus (TROPHY) Registry Study-6 Months Follow-up Data. ESPN 29: Wassef CE, Thomale UW, LoPresti MA, et al (2024) Experience in endoscope choice for neuroendoscopic lavage for intraventricular hemorrhage of prematurity: a systematic review. Childs Nerv Syst 40:2373–2384. https://doi.org/10.1007/s00381-024-06408-6 Collaborators D-U (2022) A standardised protocol for neuro-endoscopic lavage for post-haemorrhagic ventricular dilatation: A Delphi consensus approach. Childs Nerv Syst Nov 38:2181–2187. https://doi.org/10.1007/s00381-022-05632-2 Additional Declarations No competing interests reported. Supplementary Files SupplementaryFigure2.tiff SupplementaryFig.1.tiff Cite Share Download PDF Status: Published Journal Publication published 13 Nov, 2025 Read the published version in Child's Nervous System → Version 1 posted Editorial decision: Revision requested 28 Aug, 2025 Reviews received at journal 26 Aug, 2025 Reviewers agreed at journal 19 Aug, 2025 Reviewers agreed at journal 16 Aug, 2025 Reviewers invited by journal 16 Aug, 2025 Editor assigned by journal 26 Jun, 2025 Submission checks completed at journal 26 Jun, 2025 First submitted to journal 23 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6960828","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":502350446,"identity":"6105c2ea-b0e1-4ecc-8e8c-81877dfe927f","order_by":0,"name":"Sunny Abdelmageed","email":"","orcid":"","institution":"Ann and Robert H. Lurie Children’s Hospital of Chicago","correspondingAuthor":false,"prefix":"","firstName":"Sunny","middleName":"","lastName":"Abdelmageed","suffix":""},{"id":502350447,"identity":"a4216378-01cd-49ac-b81f-bd2a00310281","order_by":1,"name":"Lucinda Chiu","email":"","orcid":"","institution":"Rush University Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Lucinda","middleName":"","lastName":"Chiu","suffix":""},{"id":502350448,"identity":"a340d249-5349-4b29-8ee1-b37f2bd239f0","order_by":2,"name":"Maria Dizon","email":"","orcid":"","institution":"Ann and Robert H. Lurie Children’s Hospital of Chicago","correspondingAuthor":false,"prefix":"","firstName":"Maria","middleName":"","lastName":"Dizon","suffix":""},{"id":502350449,"identity":"5e03bf61-dcb4-42aa-aaca-1b1a5f6db12b","order_by":3,"name":"Ulrich-Wilhelm Thomale","email":"","orcid":"","institution":"Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health","correspondingAuthor":false,"prefix":"","firstName":"Ulrich-Wilhelm","middleName":"","lastName":"Thomale","suffix":""},{"id":502350453,"identity":"50358b2a-7e0f-4106-bbce-39ebc2a9ebd4","order_by":4,"name":"Jeffrey S. Raskin","email":"","orcid":"","institution":"Ann and Robert H. Lurie Children’s Hospital of Chicago","correspondingAuthor":false,"prefix":"","firstName":"Jeffrey","middleName":"S.","lastName":"Raskin","suffix":""},{"id":502350454,"identity":"d9b7178b-3cf0-4be2-b054-58c3aeb71755","order_by":5,"name":"Michael DeCuypere","email":"","orcid":"","institution":"Ann and Robert H. Lurie Children’s Hospital of Chicago","correspondingAuthor":false,"prefix":"","firstName":"Michael","middleName":"","lastName":"DeCuypere","suffix":""},{"id":502350455,"identity":"99a229f5-b51e-4ce2-9571-30acee5a3000","order_by":6,"name":"Jonathan Scoville","email":"","orcid":"","institution":"Ann and Robert H. Lurie Children’s Hospital of Chicago","correspondingAuthor":false,"prefix":"","firstName":"Jonathan","middleName":"","lastName":"Scoville","suffix":""},{"id":502350456,"identity":"56222f3e-008b-499f-9bd7-14a30213e1f5","order_by":7,"name":"Sandi Lam","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA70lEQVRIiWNgGAWjYDACdiD+UMDAwAZCCQXMRGgBqmGcYQDTYkCkFmYeAzATqIsYLfLNzE832xgczudjb3724IGBdT6/dPsDho97anFqMTjMZnY7x+CwZRvPMXODBIN0y5lzzhgwznh2HLcWZgawFgM2iRw2iQQgw+BGDtCpB47hcRj7t9sWIC3ybyBa7G+kP8CrheEwj9ltBrAtPFBbgCRQSw0ev/CU3ewxSDdg40kzAypON5C4kWNwcMaBA7gd1t6+7caPCmsD+fbDzyRBDP4Z6Q8ffDhQh9thWAHQisMkagECUm0ZBaNgFIyCYQwAEF9OH46t30kAAAAASUVORK5CYII=","orcid":"","institution":"Ann and Robert H. Lurie Children’s Hospital of Chicago","correspondingAuthor":true,"prefix":"","firstName":"Sandi","middleName":"","lastName":"Lam","suffix":""}],"badges":[],"createdAt":"2025-06-24 02:53:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6960828/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6960828/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00381-025-06994-z","type":"published","date":"2025-11-13T15:56:57+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":89977394,"identity":"95d578de-1a72-4878-90ea-4a661fbae06b","added_by":"auto","created_at":"2025-08-27 06:09:16","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":238175,"visible":true,"origin":"","legend":"\u003cp\u003eThe multidisciplinary care pathway utilized at our institution for management of patients with premature IVH. Indications for neurosurgery consultation, neurosurgical intervention, and types of neurosurgical intervention are listed.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/d2299f645cd4709c5f51e4d2.png"},{"id":89977395,"identity":"97941b29-bf0d-409a-884b-c44ea6a52d84","added_by":"auto","created_at":"2025-08-27 06:09:16","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":98279,"visible":true,"origin":"","legend":"\u003cp\u003eRepresentation of neuroendoscopes utilized for NEL in order of smallest to largest size (left to right). Each endoscope working channel is color coded here. The working portal (blue, left/bottom) allows different instruments to be passed though, including a bipolar or grasping forceps. The optic channel for visualization is shown in pink (right/top), and the inflow/outflow portals for irrigation and CSF is shown in yellow (left/right). Of note, the flexible endoscope does not have an inflow/outflow portal. All scopes are from Karl Storz [Storz, Tuttlingen, Germany] except the Minop scope [Aesculap, Tuttlingen, Germany]\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/3f990873697d58957755184f.png"},{"id":89977397,"identity":"b0834b0a-4766-45f2-b1e7-3b9da4546868","added_by":"auto","created_at":"2025-08-27 06:09:16","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":600493,"visible":true,"origin":"","legend":"\u003cp\u003eThis figure demonstrates the neuroendoscopic lavage procedure (NEL). The brain is depicted from a lateral view. The neuroendoscope is depicted in gray with, two sets of arrows are visible blue (right) to represent the inflow of saline irrigation during the procedure and red (left) to represent the outflow of bloody CSF. Tubing for inflow and outflow, neuroendoscope camera, and syringe attached to 3-way stopcock in-line with tubing are not shown here.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/6cbfef77092db21f681c6826.png"},{"id":89979059,"identity":"a8bc2a9d-ea15-4c4f-ac51-e2bcdc1fd2b1","added_by":"auto","created_at":"2025-08-27 06:17:16","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":93369,"visible":true,"origin":"","legend":"\u003cp\u003eGraphs depicting linear regression performed for medical comorbidities (0-100%, x-axis) affecting shunt dependency rate (0-100%, y-axis) for all applicable cohorts. The linear regression line is in red and R\u003csup\u003e2 \u003c/sup\u003evalue is depicted for each graph. As seen in the legend at the bottom markers depict the study cohort: circle for the present study, triangle for Tirado-Caballero and square for Honeyman. These depicts very strong positive correlations between necrotizing enterocolitis rate (NEC) and shunt dependency, R\u003csup\u003e2\u003c/sup\u003e=0.999 (left), patent ductus arteriosus rate (PDA) and shunt dependency, R\u003csup\u003e2\u003c/sup\u003e=0.975 (middle), and hyaline membrane disease (HMD) and shunt dependency, R\u003csup\u003e2\u003c/sup\u003e=0.950) (right).\u0026nbsp;\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/f4cfaca5fa2433cee4209cae.png"},{"id":89977403,"identity":"cc5794b6-44c7-47dc-9d4c-fc8618f82080","added_by":"auto","created_at":"2025-08-27 06:09:16","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":104429,"visible":true,"origin":"","legend":"\u003cp\u003eGraphs depicting linear regression performed for prematurity (x-axis) affecting shunt dependency rate (0-100%, y-axis) for all applicable cohorts. The linear regression line is in red and R\u003csup\u003e2 \u003c/sup\u003evalue is depicted for each graph. Right depicts a moderate negative correlation between birth weight and shunt dependency, R\u003csup\u003e2\u003c/sup\u003e=0.380. Left depicts a strong negative correlation between gestational age (GA) and shunt dependency R\u003csup\u003e2\u003c/sup\u003e=0.527\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/70d33aad4aa0dd67d460d53b.png"},{"id":96105320,"identity":"0383d4fc-75bb-423c-8701-fce1b2ea8336","added_by":"auto","created_at":"2025-11-17 16:11:07","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1940132,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/1bd62bbe-579b-4598-b06a-370cff40f080.pdf"},{"id":89977408,"identity":"87031ef3-7382-4494-87c7-4888236aa38c","added_by":"auto","created_at":"2025-08-27 06:09:16","extension":"tiff","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":8629978,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryFigure2.tiff","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/975dd22b2aed5911075980d1.tiff"},{"id":89977418,"identity":"e1d4a3a3-e52b-44e4-b786-6a27b7016f4e","added_by":"auto","created_at":"2025-08-27 06:09:18","extension":"tiff","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":38507012,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryFig.1.tiff","url":"https://assets-eu.researchsquare.com/files/rs-6960828/v1/f103a65b75efa4d6c225f773.tiff"}],"financialInterests":"No competing interests reported.","formattedTitle":"Neuroendoscopic Lavage: a single-center retrospective cohort in in the United States","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIntraventricular hemorrhage (IVH) is a serious complication of prematurity, impacting 20\u0026ndash;40% of premature births weighing\u0026thinsp;\u0026lt;\u0026thinsp;1.5 kilograms (kg) worldwide [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Risk of severe IVH is inversely associated with infant maturity, as represented by gestational age (GA) and birth weight (BW), with mortality rates up to 40% [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eSeveral factors contribute to the morbidity and mortality of severe IVH including injury from the primary hemorrhage and secondary complications. Of patients with IVH, 25\u0026ndash;50% of infants\u0026thinsp;\u0026lt;\u0026thinsp;1500 g will develop posthemorrhagic hydrocephalus (PHH) requiring neurosurgical intervention [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. IVH may elevate concentrations of transforming growth factor-β (TGF-β) and other cytokines potentially exacerbating cerebral damage and neuroinflammation [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eNeurosurgical treatments for IVH include ventriculosubgaleal shunts (VSGS), lumbar punctures, ventricular aspiration, and ventricular access devices (VAD) [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Despite multiple studies and guidelines there is no treatment consensus [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Drainage, irrigation, and fibrinolytic therapy (DRIFT) was a randomized controlled trial that, despite early discontinuation due to hemorrhage-associated morbidity, did show decreased shunt dependency compared with standard treatment through ten year follow up [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Neuroendoscopic lavage (NEL), guided by the DRIFT framework, enables early IVH blood products via controlled endoscopy, with lower rebleed rates, favorable outcomes in multiple European cohorts, and level III CNS guideline support [\u003cspan additionalcitationids=\"CR10 CR11 CR12 CR13 CR14 CR15\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDespite multiple European studies, there is a paucity of studies from North America. A recent study conducted in the United States (US) reported an initial favorable experience with NEL [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Variations in neonatal populations and practices between the US and Europe may reveal cohort differences impacting IVH severity and outcomes. We report our initial experience with NEL in a US cohort of patients with IVH of prematurity and PHH.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003ePatient Selection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll very preterm neonates (\u0026lt;32 weeks) with IVH of prematurity and PHH who underwent NEL at our institution from 2020-2023 with a minimum eighteen month follow up were included for retrospective chart review. Indications for neurosurgical evaluation were based on our modification of the Hydrocephalus Clinical Research Network (HCRN) clinical care pathway [18]. \u0026nbsp;Each surgical intervention was based on multidisciplinary neonatology/neurosurgery collaboration \u003cstrong\u003e(Figure 1)\u003c/strong\u003e. Patients with grade I/II IVH hemodynamic instability, and/or uncorrectable coagulopathy were excluded from NEL. This study was approved by our Institutional Review Board (IRB#2023-6158).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEndoscopes\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFlexible (Storz, Tuttlingen, Germany) and rigid endoscopes (Minop Rigid [Aesculap, Tuttlingen, Germany] Lotta and Little Lotta [Storz, Tuttlingen, Germany]) are used, as determined by surgeon preference and equipment availability (\u003cstrong\u003eFigure 2)\u003c/strong\u003e. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNEL procedure\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eUnder general anesthesia, patients were placed supine with their head turned 90 degrees lateral, approach side facing up, on a DORO (Pro Med Instruments GmbH, Freiburg, Germany) headholder system. Thorough plastic draping kept the infant\u0026rsquo;s body warm and dry during procedural irrigation. Weight-based dosing of antibiotics were given within one hour of skin incision. The frontal incision was made two centimeters off midline, anterior to the coronal suture, and lateral to the anterior fontanelle. The endoscope was inserted into the lateral ventricle with or without ultrasound guidance. Once bloody or hemosiderin-laden cerebrospinal fluid (CSF) is encountered, warm normal saline irrigation is initiated to assist with visualization of expected anatomic landmarks for orientation. Blood products are removed via the endoscope working portal by applying gentle manual syringe suction proximally. Septostomy allowed access to the contralateral ventricle to repeat this process. Warm irrigation was continued until it ran clear. Following endoscope removal, the VSGS intraventricular catheter was placed through the same burr hole, while the tapping reservoir, and patent opening distal to the reservoir to allow for CSF egress were placed in the subgaleal space \u003cstrong\u003e(Figure 3).\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMultidisciplinary management is essential for postoperative care following NEL. Screening video electroencephalography (vEEG) was part of our clinical pathway to avoid over- or under-treatment with anti-epileptics. Additional seizure medications were given for clinical seizures or EEG changes. Head ultrasound (HUS) was followed at least weekly with de-escalation over time if the patient\u0026rsquo;s neurologic exam remained stable. If clinical or radiographic signs of hydrocephalus recurred, additional CSF diversion procedures were considered including repeat NEL, VSGS revision, endoscopic third ventriculostomy (ETV) with or without lysis of adhesions, and/or placement of shunt. Continued bedside temporization for infants \u0026lt;2kg most commonly involved VSGS reservoir taps. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePatient Factors\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatient risk factors such as GA, BW, pre-operative modified Papile grade, and comorbid conditions were reviewed. Comorbid conditions included hyaline membrane disease (HMD), persistent ductus arteriosus (PDA), necrotizing enterocolitis (NEC), meningitis (suspected or proven), and seizures.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePerioperative Events\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePerioperative events included CSF infection (defined by positive CSF cultures), secondary hemorrhage (defined by new/increased blood volume on imaging within 72 hours following surgery), and postoperative subclinical electrographic seizures (defined by detection on routine screening vEEG by the neonatal neurology team).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRadiographic Assessment and Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIVH severity was described using the modified Papile classification [19]. Grading was performed by pediatric neuroradiologists, or if unavailable, the study team. Frontal occipital horn ratio (FOHR) and ventricular index (VI) were measured from the most recent preoperative HUS (within 72 hours) of NEL and first postoperative HUS. FOHR is defined as the sum of the frontal horn width and the occipital horn width divided by two times the biparietal diameter. VI is the distance between the lateral wall of the anterior horn and the falx \u003cstrong\u003e(Supplementary figure 1).\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eVentriculoperitoneal shunt (VPS)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDecision for VPS placement after NEL+VAD/VSGS was based on surgeon assessment.\u0026nbsp;Shunt revisions were recorded for patients who received a VPS.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDelta was calculated by subtracting the preoperative measurement of VI and FOHR from the postoperative values, respectively. A paired, one-tailed Student\u0026rsquo;s T-test was used to compare pre-and post-operative FOHR and VI. P\u0026le;0.05 was considered significant. Linear regression was performed with mean prematurity and comorbidities as independent variables and mean shunt dependency rate as a dependent variable. R\u003csup\u003e2\u003c/sup\u003e values were interpreted using the following determinations: very strong (0.7-1.0), strong (0.4-0.69), moderate (0.3-0.39), and weak (0.2-0.29). Statistical analysis was completed using RStudio (RStudio Team, 2023). Studies were included in the linear regression if mean values for shunt dependency were independently reported for an NEL only group.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003ePatient Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEleven infants (five female), with BW \u0026lt;1.5 kg underwent NEL+VSGS/VAD between June 2020 and September 2023. In our cohort, 2/11 patients (18.2%) had grade III IVH, 9/11 (81.2) had grade IV IVH. The mean FOHR was 0.51\u0026nbsp;\u0026plusmn;.08 at time of consultation. All patients showed clinical and imaging findings of worsening ventriculomegaly meeting criteria for CSF diversion via temporizing measure (\u003cstrong\u003eFigure 1\u003c/strong\u003e). Patient demographics are described in \u003cstrong\u003eTable 1\u003c/strong\u003e. \u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"609\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"9\" style=\"width: 609px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 1.\u003c/strong\u003e Demographics and Surgery Characteristics\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003eCase no.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003eGA, sex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003eBW/ Weight at Sx (g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003eDOL at Sx\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 104px;\"\u003e\n \u003cp\u003eEndoscope\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eTemporizing Device\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003eOperative Time (mins)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003eLOS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003eFollow-up (days)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e24w4d, M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.89 / 1.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eFlexible Storz\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e258\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e1104\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e24w2d, F\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.75 / 1.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eFlexible Storz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e113\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e289\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e1223\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e23w0d, F\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.61/ 0.81\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eFlexible Storz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e140\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e873\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e24w0d, F\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.60 / 1.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eMinop Rigid\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e737\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e25w1d, M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.72 / 1.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eLotta Rigid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e54\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e25w3d, M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.83/ 1.65\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eMinop Rigid\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVAD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e217\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e522\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e25w5d, M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.65 / 1.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eMinop Rigid\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e146\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e475\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e27w5d, M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e1.18 / 1.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eLittle Lotta Rigid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e364\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e27w2d, F\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e1.07 / 1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eLotta Rigid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVAD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e166\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e281\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e27w0d, F\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e1.10 / 1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eLittle Lotta Rigid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e202\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e215\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 71px;\"\u003e\n \u003cp\u003e24w0d, M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.74 / 2.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003eFlexible Storz\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 54px;\"\u003e\n \u003cp\u003eVSGS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e221\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 70px;\"\u003e\n \u003cp\u003e184\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eGA, Gestational Age; M, male, F, Female; BW, birth weight Sx, surgery; IVH, intraventricular hemorrhage; DOL, day of life; kg, gram; w, weeks; d, days; VSGS, Ventriculosubgaleal shunt; VAD, Ventricular access device; LOS, length of stay\u003c/p\u003e\n\u003cp\u003eThe cohort self-identified as White (5/11, 45.5%), Black (2/11, 18.2%), Asian (1/11, 9.1%), and Other (3/11, 27.3%). Hispanic/Latino was the reported ethnicity in 3/11 patient families (27.3%). Mean gestational age at birth was 25 weeks and 2 days \u0026plusmn; 1.5 weeks. Average BW was 0.83kg (range 0.6-1.1kg). Comorbidities in this cohort included HMD in all cases, PDA in 10/11 (90.9%), NEC in 8/11 (72.3%), and meningitis in 2/11 (18.2%). Seizures were diagnosed by vEEG in 5/11 (45.5%) of the patients, with two patient seizures occurring only in the preoperative period. Prior to neurosurgical intervention, seven patients had coagulopathies and cytopenias necessitating blood product transfusions and six patients required vasopressors to maintain normotension. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe average length of stay in the neonatal intensive care unit (NICU) was 158\u0026plusmn;83 days. The mean in-hospital ventilation duration was 70.3 days (range 2-279 days). At discharge 5/10 were on room air, 3/10 required nasal canula with supplemental oxygen, and 2/10 were ventilator-dependent with a tracheostomy. Nutrition status at discharge included 1/10 taking oral feeds, 4/10 requiring a nasogastric tube, and 5/10 with a gastrostomy tube. The mean total follow-up was 29.5 months (range 1.8-52.7 months).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePerioperative variables\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAverage age at time of NEL was 40.4\u0026plusmn;21.5 days and mean weight was 1.51\u0026plusmn;0.3 kg. One patient received an NEL at 2.6 kg due to prior bowel perforation and expected future abdominal surgeries, despite meeting VPS criteria. Mean operative time was 67.5\u0026plusmn;26 minutes. Mean estimated blood loss was 1.5\u0026plusmn;0.6 milliliters \u003cstrong\u003e(Table 1).\u0026nbsp;\u003c/strong\u003eThe Storz flexible endoscope was used in four patients, the MINOP Rigid endoscope in three patients, the Lotta Rigid in two patients, and the Little Lotta Rigid in two patients. Two patients received blood product transfusions and one patient required vasopressors perioperatively. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePerioperative events\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOutcomes and perioperative events are shown in \u003cstrong\u003eTable 2\u003c/strong\u003e.\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"606\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\" style=\"width: 606px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 2.\u003c/strong\u003e Outcomes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003eCase #\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003eFOHR\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e∆\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003eVI\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(mm \u0026gt;97\u003csup\u003eth\u003c/sup\u003e)\u003c/p\u003e\n \u003cp\u003e∆\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003eOperative Time (mins)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 174px;\"\u003e\n \u003cp\u003ePerioperative events\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003eClot Burden Remaining\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003ePermanent CSF diversion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-8.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003epreop seizure\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 72px;\"\u003e\n \u003cp\u003e-9.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e113\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003epreop seizure, CSF infection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-10.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003eLocal skin Infection\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-4.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003eWound dehiscence\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003eHemorrhage, Death\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-12.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-7.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 174px;\"\u003e\n \u003cp\u003epreop seizure, vEEG seizure POD 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-4.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003eCSF infection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003evEEG seizure POD 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e2.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eyes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e-0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e-6.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 84px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 174px;\"\u003e\n \u003cp\u003evEEG seizure POD2, hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 78px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e∆\u0026nbsp;\u003c/strong\u003erepresents the change in preoperative and postoperative FOHR or VI , *data was unavailiable, #, Number; FOHR, frontal-occipital horn ratio; VI, ventricular index; LOS, length of stay; CSF, cerebrospinal fluid; vEEG, video EEG; POD, post-op day\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThere was one mortality in a patient with grade IV IVH, multiple comorbidities and redirection of goals of care. This patient was excluded from perioperative adverse event frequency calculations. CSF infection in the postoperative period was diagnosed in two patients, one with enterobacter cloacae, another with methicillin sensitive staphylococcus aureus. Two patients had secondary IVH within two days post-operatively. Four (36.4%) patients required repeat temporizing measures (all with re-do VSGS; two with and two without NEL) before definitive CSF diversion as they had hostile distal CSF shunting sites or low body weight. Three (27.3%) patients had vEEG evidence of a seizure within 72 hours postoperatively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRadiographic measurements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCranial imaging in the form of a HUS was obtained postoperatively (mean = four days, range 0-10 days). The mean FOHR decreased from 0.68 prior to NEL to 0.56 after NEL (∆ -0.12, p\u0026lt;0.001, \u003cstrong\u003eTable 2\u003c/strong\u003e). The VI \u0026gt;97\u003csup\u003eth\u003c/sup\u003e percentile decreased from 11.8 mm prior to NEL to 6.2 mm after NEL (∆ -5.6, p\u0026lt;0.001). Following NEL all IVH grades were stable or improved: one patient had grade 0, three patients had grade I, three had grade II, one had grade III, an four had grade IV IVH.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePermanent CSF diversion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatients had an average follow-up of 30 months. Eight patients thus far have required permanent CSF diversion. Seven patients had a VPS placed and one had a ventriculoatrial shunt placed given a hostile abdomen. Mean time between NEL and shunt insertion time was 149 days. Mean age at shunt insertion was 6.1\u0026plusmn;5.6 months and the mean weight was 3.87\u0026plusmn;1.8 kg. The mean number of revisions was 1.6. Four patients required at least one revision at 23, 28, 119 and 120 days. The remaining four patients have not required shunt revisions (mean 33\u0026plusmn;10.4 months). Revision free shunt-survival at one year was 50%. The Kaplan-Meier curve for revision free shunt-survival is shown in \u003cstrong\u003eSupplementary Figure 2\u003c/strong\u003e. Four of eleven patients developed multiloculated hydrocephalus. Neuroendoscopic fenestration enabled all cases to be successfully managed by a single ventricular catheter.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCompared with most European cohorts our patients demonstrated higher shunt dependency rates (\u003cstrong\u003eTable 3\u003c/strong\u003e).\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\" valign=\"top\" style=\"width: 616px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 3.\u003c/strong\u003e Comparison with published cohorts\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003eLurie\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003eSchulz, 2014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003eD\u0026rsquo;Arcangues, 2018\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003eTirado-Caballero, 2020\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003eFrassanito 2021\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003eHoneyman, 2022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003eFlanders, 2025\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eN=\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e12^\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eGA at Birth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e25w2d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e27w6d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e27w6d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e30w1d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e28w5d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e29w4d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e25w0d\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eBirth Weight (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e0.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e1.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e1.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e1.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\" valign=\"bottom\" style=\"width: 616px;\"\u003e\n \u003cp\u003eIVH Grade\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e0 (0.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e2 (10.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e5 (8.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e0 (0.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e1 (3.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;III\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e2 (18.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e13 (68.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e23 (41.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e28 (60.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e8 (3.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;IV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e9 (81.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e3(15.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e28 (50.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e18 (39.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e17 (65.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\" valign=\"bottom\" style=\"width: 616px;\"\u003e\n \u003cp\u003eComorbid Conditions\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; HMD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e11 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e22 (47.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e18 (69.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; NEC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e8 (72.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e5 (10.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e11 (42.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; PDA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e10 (90.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e11 (23.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e17 (65.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003ePMA at NEL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e30.86w\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e31.71w\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e31.28w\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e32.7w\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e39.6w\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e29.82w\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eWeight at NEL (g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e1.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e1.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e1.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\" valign=\"bottom\" style=\"width: 616px;\"\u003e\n \u003cp\u003ePerioperative Events\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eCSF \u0026nbsp; \u0026nbsp;Infection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e2 (18.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e2 (10.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e2 (3.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e10 (21.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1 (4.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e2 (7.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1 (8.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Re-bleed\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e2 (18.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e5 (8.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e3 (6.52%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e1 (3.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1 (8.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Death\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e1 (9.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e3 (5.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e3 (6.52%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1 (4.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e0 (0.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1 (8.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003ePermanent CSF diversion\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e72.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e58.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e56.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e58.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e5.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e72.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eTime to Shunt (w)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e10.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e6.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e4.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e10.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003e1-year Shunt Survival\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e50%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e63.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e50%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e64.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 88px;\"\u003e\n \u003cp\u003eMedian # of Procedures\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 79px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 85px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 87px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 73px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 66px;\"\u003e\n \u003cp\u003e*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*data was not available ; ^Flanders et al. Only reported demographic information for 11 patients; #, number\u003c/p\u003e\n\u003cp\u003eLinear regression between comorbidities and shunt dependency were performed using patient-level values reported in Tirado-Caballero et al. and Honeyman et al [13, 14].There was a very strong positive correlation between HMD rate (R\u003csup\u003e2\u003c/sup\u003e=0.950), NEC (R\u003csup\u003e2\u003c/sup\u003e=0.999) and PDA (R\u003csup\u003e2\u003c/sup\u003e=0.975) and shunt dependency (\u003cstrong\u003eFigure 4\u003c/strong\u003e).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eLinear regression between prematurity was performed using data from five published cohorts [10, 12\u0026ndash;14, 17]. There was a strong negative correlation between gestational age and shunt dependency, GA (R\u003csup\u003e2\u003c/sup\u003e=0.527) and moderate negative correlation between BW and shunt dependency (R\u003csup\u003e2\u003c/sup\u003e=0.344, \u003cstrong\u003eFigure 5\u003c/strong\u003e). \u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis retrospective cohort study describes a single-center US experience with NEL. This US cohort is similar in average GA (25 weeks and 2 days) and BW (0.87 kg) to one published in another US institution (average GA 25 weeks, BW 0.78 kg) [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Prior studies have shown the incidence of IVH is significantly higher in North American compared to European cohorts (p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and that the incidence proportion of severe IVH for GA 25\u0026ndash;27 weeks is higher in North America as well (North America: 0.22, Europe 0.16) [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. When compared with European cohorts, our patients are more premature with greater medical comorbidities. These differences may reflect variations in neonatal populations and practices between the US and Europe. [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Comorbid conditions in our cohort included higher rates of HMD, bronchopulmonary dysplasia, PDA, and NEC, which corresponds with 55% of our patients being discharged on respiratory support and 91% with nutritional support with tube feeds. Our cohort also had longer average mechanical ventilation duration (70.3 days) versus four days in D\u0026rsquo;Arcangues et al cohort [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eComplication rates in this study are similar to previous NEL cohorts. Secondary hemorrhage is similar to European cohorts (18.2%), and is lower than in DRIFT (35% [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Screening vEEG detected post-operative seizures in 27.3% of our patients. This modality gives perspective on the incidence of perioperative seizures in these patients: data that has not been previously quantified or explored in published cohorts. It also allows for early seizure detection and timely treatment, which is critical as the number of days with EEG-confirmed seizures has been identified as a potentially modifiable risk factor to developing postnatal epilepsy [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Our observed CSF infection rate was lower than the Spanish cohort and higher than the published UK and German cohorts [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn our study, one patient died postoperatively. This mortality rate is consistent with previously published cohorts, reflecting the medical complexity and fragility of these patients, and underscoring the need for multidisciplinary care and ongoing research. A prospective study of the impact of IVH on mortality in very preterm (26\u0026ndash;32 weeks GA) and low BW infants (\u0026lt;\u0026thinsp;1.5 kg) found that patients with grade III/IV IVH were 14 times more likely to die before NICU discharge compared with grade I/II IVH; surgical interventions for IVH were not reported [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In the North America HCRN Shunting Outcomes in Posthemorrhagic Hydrocephalus (SOPHH) study, 12.7% (13 of the premature infants\u0026thinsp;\u0026lt;\u0026thinsp;1.5kg BW) who underwent a VAD/VSGS died within six months post-operatively [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. A 15-year retrospective study from our institution prior to adoption of NEL similarly found a 10% mortality (n\u0026thinsp;=\u0026thinsp;3) after temporizing measure (VSGS/VAD) for grade III/IV IVH ([\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Amongst both the German and Spanish NEL series (n\u0026thinsp;\u0026gt;\u0026thinsp;45), they each reported three deaths (6.6%) [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Similarly, Flanders et al. reported one death (8.3%) among their US NEL patients [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Our mortality case had family wishes for redirection of goals of care after encountering refractory coagulopathy, acute anemia, large volume transfusions, and cardiopulmonary arrest.\u003c/p\u003e\u003cp\u003eOur rate of permanent CSF diversion was 72.7% compared to published European cohorts of 56-87.9% [\u003cspan additionalcitationids=\"CR13 CR14\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. This rate is lower than shunt dependency rates reported in our prior retrospective study (77.8%) for grade III/IV IVH and other US studies after VAD/VSGS alone (90\u0026ndash;95%) [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Flanders et al, whose US cohort had similar BW and GA to this cohort, also reported a permanent CSF diversion rate of 72.7% [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Severe prematurity is a significant risk factor for PHH and subsequent need for VP shunt insertion [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Pooling data from the studies above increased prematurity and medical comorbidities were associated with greater hunt dependency. A learning curve has also been described. Tirado-Caballero et al saw a 72.72% rate of permanent shunting in their first 11 patients; in subsequent epochs in their experience, this rate dropped to \u0026lt;\u0026thinsp;54% [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. A 2020 Italian retrospective study of 63 infants reported an 87.9% rate of permanent CSF diversion when comparing VSGS and VSGS\u0026thinsp;\u0026plusmn;\u0026thinsp;NEL for PHH. Shunt dependency may also be influenced by the extent of IVH. Our series only included grade III/IV IVH patients, with 81.2% having grade IV. Grade IV IVH has a 52% increased risk of shunt dependency as compared to grade II IVH, regardless of intervention [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. European studies include patients with Grade II IVH; this variability precludes direct comparison.\u003c/p\u003e\u003cp\u003eSurgical timing in preterm infants with IVH involves multidisciplinary risk-benefit assessment. While our time-to-intervention from birth to NEL (5.7 weeks) was longer than most European studies (3.95 weeks), it was more similar to the other US cohort (4.82 weeks). Previous studies have demonstrated improved outcomes and reduced shunt rates with earlier intervention [\u003cspan additionalcitationids=\"CR30\" citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Others have suggested ventriculomegaly indices thresholds of FOHR\u0026thinsp;\u0026ge;\u0026thinsp;0.66, VI\u0026thinsp;\u0026ge;\u0026thinsp;8.4mm above the 97th percentile prior to CSF diversion [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. We noted an increased time from NEL to shunt insertion of 10.4 weeks for those with NEL versus six weeks without NEL in our historical cohort [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The differences in GA at birth and comorbidity burden may also influence timing of shunt insertion. Distal shunt site can be challenging in these patients: two had bowel resections with inhospitable abdomens and four had long-term venous catheters terminating in the right atrium. Ventriculopleural shunts are typically not considered in this age range and is further contraindicated by our patients\u0026rsquo; respiratory complications of prematurity.\u003c/p\u003e\u003cp\u003eAnother reported benefit of NEL is the reduction of complex hydrocephalus [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Previously conventional treatment cohorts report a median of 3.5 shunt revisions [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Our study had a median of two neurosurgical procedures. While we recognize that secondary shunt failures are multifactorial and not always preventable, our NEL series has had successful avoidance of multi-catheter multiloculated hydrocephalus. Four patients in our series required additional neuroendoscopic fenestration which has been durable thus far, with none requiring multiple catheter systems. Similarly, the one-year revision free shunt survival in this small US cohort of 50% is similar to European cohorts, and it compares to historically reported rates of 44% in European and US cohorts (13\u0026ndash;15, 32). Neurodevelopmental outcomes will be discerned at longer term follow up. The Treatment of Post-Hemorrhagic Hydrocephalus (TROPHY) international prospective database seeks to compare various temporizing measures and is expected to yield additional multicenter information on NEL safety, efficacy, and neurodevelopmental outcomes [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e], and has encouraging 6 month follow up results so far.[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]\u003c/p\u003e\u003cp\u003eLimitations include those inherent to single institution retrospective series with small sample size and relatively short follow up as our cohort matures. Neurodevelopmental outcomes at two and five years follow up will be essential. In addition, our center included three neurosurgeons with evolving access to four endoscopes in the timeframe of the study [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. D\u0026rsquo;Arcangues et al. only used rigid endoscopes with inflow/outflow channels, while the ongoing ENLIVEN-UK randomized controlled trial recruiting across 11 UK centers does not prescribe a standard endoscopic choice [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. For each center, experience using neuroendoscopy, development of standardized perioperative protocols, and multidisciplinary collaboration of neonatology, neurology, neurosurgery, and neuroanesthesiology teams are essential.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study shares our single US institution\u0026rsquo;s initial NEL experience for IVH of prematurity and PHH in a group with greater comorbidities and lower mean GA and birth weight compared with published European cohorts. Further studies are necessary to define the risks and benefits of NEL, the criteria for optimal case selection, and the most appropriate outcomes measures, including long-term neurodevelopment.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eNeuroendoscopic lavage= NEL; intraventricular hemorrhage= IVH; Gestational Age= GA; kilograms= kg; Birth weight= BW; posthemorrhagic hydrocephalus= PHH; ventriculosubgaleal shunts= VSGS; ventricular access devices (VAD); Drainage, irrigation, and fibrinolytic therapy= DRIFT; Hydrocephalus Clinical Research Network =HCRN; cerebrospinal fluid= CSF; video electroencephalography=vEEG; head ultrasound= HUS; endoscopic third ventriculostomy= ETV; hyaline membrane disease=HMD; persistent ductus arteriosus= PDA; necrotizing enterocolitis=NEC; Frontal occipital horn ratio= FOHR; ventricular index=VI; ventriculoperitoneal shunt=VPS; neonatal intensive care unit= NICU; Shunting Outcomes in Posthemorrhagic Hydrocephalus= SOPHH; Treatment of Post-Hemorrhagic Hydrocephalus= TROPHY\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAcknowledgements: The authors acknowledge Megan Votoupal for her help with data collection and study coordination as well as Samantha Leon for her help with initial data extraction.\u003c/p\u003e\n\u003cp\u003eCompeting interests: The authors have no conflicts of interest or funding sources to disclose. We confirm that we have read the journal\u0026rsquo;s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.\u003c/p\u003e\n\u003cp\u003eEthics approval: This retrospective chart review study involving human participants was in accordance with the ethical standards of the declaration of Helsinki. The Ann \u0026amp; Robert H. Lurie Children\u0026rsquo;s Hospital of Chicago (LCH) Institutional Review Board approved this study prior to its initiation (IRB: 2023-6158). \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConsent: Written informed consent was obtained from patients/parents prior to treatment. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eData transparency:\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eAll relevant data is included in the manuscript body. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAuthor Contributions: Conceptualization: Sunny Abdelmageed, Sandi Lam; Methodology: Sunny Abdelmageed, Jonathan Scoville, Sandi Lam; Data Curation- Sunny Abdelmageed, Lucinda Chiu; Formal analysis and investigation: Sunny Abdelmageed; Writing-original draft preparation: Sunny Abdelmageed, Lucinda Chiu; Writing- review and editing: Sunny Abdelmageed, Lucinda Chiu, Maria Dizon MD, Ulrich- Wilhelm Thomale, Jeffrey S. Raskin, Michael DeCuypere, Sandi Lam Resources: Maria Dizon, Jeffrey S. Raskin, Michael DeCuypere, Sandi Lam; Visualization- Sunny Abdelmageed, Lucinda Chiu, Jonathan Scoville, \u0026nbsp;Ulrich-Wilhem Thomale, Sandi Lam; Supervision: Jeffrey S. Raskin. All authors have read and approved the final version of the manuscript. Sandi Lam is responsible for the overall content of the manuscript and serves as the guarantor. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eEl-Atawi K (2016) Risk Factors, Diagnosis, and Current Practices in the Management of Intraventricular Hemorrhage in Preterm Infants: A Review. Acad J Pediatr Neonatol 1:. https://doi.org/10.19080/AJPN.2016.01.555561\u003c/li\u003e\n\u003cli\u003eBolisetty S, Dhawan A, Abdel-Latif M (2014) Intraventricular hemorrhage and neurodevelopmental outcomes in extreme preterm infants. Pediatr Jan 133:55\u0026ndash;62. https://doi.org/10.1542/peds.2013-0372\u003c/li\u003e\n\u003cli\u003eChristian EA, Melamed EF, Peck E, et al (2016) Surgical management of hydrocephalus secondary to intraventricular hemorrhage in the preterm infant. J Neurosurg Pediatr Mar 17:278\u0026ndash;84. https://doi.org/10.3171/2015.6.PEDS15132\u003c/li\u003e\n\u003cli\u003eSherlock RL, Anderson PJ, Doyle LW, Victorian Infant Collaborative Study G (2005) Neurodevelopmental sequelae of intraventricular haemorrhage at 8 years of age in a regional cohort of ELBW/very preterm infants. Early Hum Dev Nov 81:909\u0026ndash;16. https://doi.org/10.1016/j.earlhumdev.2005.07.007\u003c/li\u003e\n\u003cli\u003eLuu TM, Ment LR, Schneider KC, et al (2009) Lasting effects of preterm birth and neonatal brain hemorrhage at 12 years of age. Pediatr Mar 123:1037\u0026ndash;44. https://doi.org/10.1542/peds.2008-1162\u003c/li\u003e\n\u003cli\u003eHolste KG, Xia F, Ye F, et al (2022) Mechanisms of neuroinflammation in hydrocephalus after intraventricular hemorrhage: a review. Fluids Barriers CNS Apr 19:. https://doi.org/10.1186/s12987-022-00324-0\u003c/li\u003e\n\u003cli\u003eWhitelaw A, Pople I, Cherian S, et al (2003) Phase 1 Trial of Prevention of Hydrocephalus After Intraventricular Hemorrhage in Newborn Infants by Drainage, Irrigation, and Fibrinolytic Therapy. Pedatrics April 2003;111(4):759\u0026ndash;765:. https://doi.org/10.1542/peds.111.4.759\u003c/li\u003e\n\u003cli\u003eDeger J, Goethe EA, LoPresti MA, Lam S (2021) Intraventricular Hemorrhage in Premature Infants: A Historical Review. World Neurosurg Sep 153:21\u0026ndash;25. https://doi.org/10.1016/j.wneu.2021.06.043\u003c/li\u003e\n\u003cli\u003eMazzola CA, Choudhri AF, Auguste KI (2014) Pediatric hydrocephalus: systematic literature review and evidence-based guidelines. Part 2: Management of posthemorrhagic hydrocephalus in premature infants. J Neurosurg Pediatr Nov 1:8\u0026ndash;23. https://doi.org/10.3171/2014.7.PEDS14322\u003c/li\u003e\n\u003cli\u003eSchulz M, Buhrer C, Pohl-Schickinger A, et al (2014) Neuroendoscopic lavage for the treatment of intraventricular hemorrhage and hydrocephalus in neonates. J Neurosurg Pediatr Jun 13:626\u0026ndash;35. https://doi.org/10.3171/2014.2.PEDS13397\u003c/li\u003e\n\u003cli\u003eBehrens P, Tietze A, Walch E (2020) Neurodevelopmental outcome at 2 years after neuroendoscopic lavage in neonates with posthemorrhagic hydrocephalus. J Neurosurg Pediatr Aug 26:495\u0026ndash;503. https://doi.org/10.3171/2020.5.PEDS20211\u003c/li\u003e\n\u003cli\u003ed\u0026rsquo;Arcangues C, Schulz M, Buhrer C, et al (2018) Extended Experience with Neuroendoscopic Lavage for Posthemorrhagic Hydrocephalus in Neonates. World Neurosurg Aug 116:e217-e224:. https://doi.org/10.1016/j.wneu.2018.04.169\u003c/li\u003e\n\u003cli\u003eTirado-Caballero J, Rivero-Garvia M, Arteaga-Romero F, et al (2020) Neuroendoscopic lavage for the management of posthemorrhagic hydrocephalus in preterm infants: safety, effectivity, and lessons learned. J Neurosurg Pediatr May 26:237\u0026ndash;246. https://doi.org/10.3171/2020.2.PEDS2037\u003c/li\u003e\n\u003cli\u003eHoneyman SI, Boukas A, Jayamohan J, Magdum S (2022) Neuroendoscopic lavage for the management of neonatal post-haemorrhagic hydrocephalus: a retrospective series. Childs Nerv Syst Jan 38:115\u0026ndash;121. https://doi.org/10.1007/s00381-021-05373-8\u003c/li\u003e\n\u003cli\u003eFrassanito P, Serrao F, Gallini F (2021) Ventriculosubgaleal shunt and neuroendoscopic lavage: refining the treatment algorithm of neonatal post-hemorrhagic hydrocephalus. Childs Nerv Syst 37:3531\u0026ndash;3540. https://doi.org/10.1007/s00381-021-05216-6\u003c/li\u003e\n\u003cli\u003eKandula V, Mohammad LM, Thirunavu V, et al (2022) The role of blood product removal in intraventricular hemorrhage of prematurity: a meta-analysis of the clinical evidence. Childs Nerv Syst 38:239\u0026ndash;252. https://doi.org/10.1007/s00381-021-05400-8\u003c/li\u003e\n\u003cli\u003eFlanders TM, Hwang M, Julian NW, et al (2025) Neuroendoscopic lavage for posthemorrhagic hydrocephalus of prematurity: preliminary results at a single institution in the United States. J Neurosurg Pediatr 35:345\u0026ndash;352. https://doi.org/10.3171/2024.10.PEDS24119\u003c/li\u003e\n\u003cli\u003eWellons JC, Shannon CN, Holubkov R, et al (2017) Shunting outcomes in posthemorrhagic hydrocephalus: results of a Hydrocephalus Clinical Research Network prospective cohort study. J Neurosurg Pediatr 20:19\u0026ndash;29. https://doi.org/10.3171/2017.1.PEDS16496\u003c/li\u003e\n\u003cli\u003ePapile LA, Burstein J, Burstein R, Koffler H (1978) Incidence and evolution of subependymal and intraventricular hemorrhage: a study of infants with birth weights less than 1,500 gm. J Pediatr Apr 92:529\u0026ndash;34. https://doi.org/10.1016/s0022-3476(78)80282-0\u003c/li\u003e\n\u003cli\u003eLai GY, Shlobin N, Garcia RM, et al (2022) Global incidence proportion of intraventricular haemorrhage of prematurity: a meta-analysis of studies published 2010-2020. Arch Child Fetal Neonatal Ed 107:513\u0026ndash;519. https://doi.org/10.1136/archdischild-2021-322634\u003c/li\u003e\n\u003cli\u003eSingh J, Fanaroff J, Andrews B (2007) Resuscitation in the \u0026ldquo;gray zone\u0026rdquo; of viability: determining physician preferences and predicting infant outcomes. Pediatr Sep 120:519\u0026ndash;26. https://doi.org/10.1542/peds.2006-2966\u003c/li\u003e\n\u003cli\u003eWhitelaw A, Jary S, Kmita G (2010) Randomized trial of drainage, irrigation and fibrinolytic therapy for premature infants with posthemorrhagic ventricular dilatation: developmental outcome at 2 years. Pediatr Apr 125:. https://doi.org/10.1542/peds.2009-1960\u003c/li\u003e\n\u003cli\u003eShellhaas RA, Wusthoff CJ, Numis AL, et al (2021) Early-life epilepsy after acute symptomatic neonatal seizures: A prospective multicenter study. Epilepsia 62:1871\u0026ndash;1882. https://doi.org/10.1111/epi.16978\u003c/li\u003e\n\u003cli\u003ePascal A, Bruyn N, Naulaers G (2023) The Impact of Intraventricular Hemorrhage and Periventricular Leukomalacia on Mortality and Neurodevelopmental Outcome in Very Preterm and Very Low Birthweight Infants: A Prospective Population-based Cohort Study. J Pediatr 262:. https://doi.org/10.1016/j.jpeds.2023.113600\u003c/li\u003e\n\u003cli\u003eLai GY, Abdelmageed S, DeRegnier R-AO, et al (2022) Degree of ventriculomegaly predicts school-aged functional outcomes in preterm infants with intraventricular hemorrhage. Pediatr Res 91:1238\u0026ndash;1247. https://doi.org/10.1038/s41390-021-01631-2\u003c/li\u003e\n\u003cli\u003eFlanders TM, Hwang M, Julian NW, et al (2024) Technique and protocol for bedside neuroendoscopic lavage for post-hemorrhagic hydrocephalus: technical note. Childs Nerv Syst ChNS Off J Int Soc Pediatr Neurosurg 41:39. https://doi.org/10.1007/s00381-024-06697-x\u003c/li\u003e\n\u003cli\u003eBock HC, Feldmann J, Ludwig HC (2018) Early surgical management and long-term surgical outcome for intraventricular hemorrhage-related posthemorrhagic hydrocephalus in shunt-treated premature infants. J Neurosurg Pediatr Jul 22:61\u0026ndash;67. https://doi.org/10.3171/2018.1.PEDS17537\u003c/li\u003e\n\u003cli\u003eHorbar JD, Badger GJ, Carpenter JH (2002) Trends in mortality and morbidity for very low birth weight infants, 1991-1999. Pediatr Jul 110:143\u0026ndash;51. https://doi.org/10.1542/peds.110.1.143\u003c/li\u003e\n\u003cli\u003eCizmeci MN, Groenendaal F, Liem KD (2020) Randomized Controlled Early versus Late Ventricular Intervention Study in Posthemorrhagic Ventricular Dilatation: Outcome at 2 Years. J Pediatr Nov 226:28\u0026ndash;35. https://doi.org/10.1016/j.jpeds.2020.08.014\u003c/li\u003e\n\u003cli\u003eLai GY, Chu-Kwan W, Westcott AB, et al (2021) Timing of Temporizing Neurosurgical Treatment in Relation to Shunting and Neurodevelopmental Outcomes in Posthemorrhagic Ventricular Dilatation of Prematurity: A Meta-analysis. J Pediatr 234:54-64 e20. https://doi.org/10.1016/j.jpeds.2021.01.030\u003c/li\u003e\n\u003cli\u003eJin MC, Parker JJ, Rodrigues AJ (2022) Development of an integrated risk scale for prediction of shunt placement after neonatal intraventricular hemorrhage. J Neurosurg Pediatr Apr 29:444\u0026ndash;453. https://doi.org/10.3171/2021.11.PEDS21390\u003c/li\u003e\n\u003cli\u003eSimon TD, Whitlock KB, Riva-Cambrin J (2012) Association of intraventricular hemorrhage secondary to prematurity with cerebrospinal fluid shunt surgery in the first year following initial shunt placement. J Neurosurg Pediatr Jan 9:54\u0026ndash;63. https://doi.org/10.3171/2011.10.PEDS11307\u003c/li\u003e\n\u003cli\u003eThomale U-W, Cinalli G, Kulkarni AV (2019) TROPHY registry study design: a prospective, international multicenter study for the surgical treatment of posthemorrhagic hydrocephalus in neonates. Childs Nerv Syst 2019;35(4):613\u0026ndash;619:. https://doi.org/10.1007/s00381-019-04077-4\u003c/li\u003e\n\u003cli\u003eThomale UW, Lukoschus FN, Pennacchietti V, et al (2025) Treatment of posthemorrhagic hydrocephalus (TROPHY) Registry Study-6 Months Follow-up Data. ESPN 29:\u003c/li\u003e\n\u003cli\u003eWassef CE, Thomale UW, LoPresti MA, et al (2024) Experience in endoscope choice for neuroendoscopic lavage for intraventricular hemorrhage of prematurity: a systematic review. Childs Nerv Syst 40:2373\u0026ndash;2384. https://doi.org/10.1007/s00381-024-06408-6\u003c/li\u003e\n\u003cli\u003eCollaborators D-U (2022) A standardised protocol for neuro-endoscopic lavage for post-haemorrhagic ventricular dilatation: A Delphi consensus approach. Childs Nerv Syst Nov 38:2181\u0026ndash;2187. https://doi.org/10.1007/s00381-022-05632-2\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"childs-nervous-system","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cnsy","sideBox":"Learn more about [Child's Nervous System](http://link.springer.com/journal/381)","snPcode":"381","submissionUrl":"https://submission.nature.com/new-submission/381/3","title":"Child's Nervous System","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Intraventricular Hemorrhage, Posthemorrhagic hydrocephalus, prematurity, ventriculosubgaleal shunt","lastPublishedDoi":"10.21203/rs.3.rs-6960828/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6960828/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e\u003cp\u003eNeuroendoscopic lavage (NEL) has been described for post-hemorrhagic hydrocephalus management in intraventricular hemorrhage (IVH) or prematurity in European cohorts. We describe an initial uni-center series from the United States.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003e Retrospective review was performed for premature infants with IVH that underwent NEL at our institution between 2020\u0026ndash;2023. Patient characteristics, clinical variables, and radiological assessments were collected.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eEleven patients (five female) with IVH grade III/IV underwent 13 procedures. Mean gestational age (GA) was 25 weeks and two days. Mean birth weight (BW) was 0.83 kilograms (kg). Average age at NEL was 40.4\u0026thinsp;\u0026plusmn;\u0026thinsp;21.5 days, mean weight was 1.51\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3 kg. Mean frontal horn index decreased from 0.68 to 0.56 after NEL (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Cerebrospinal fluid infection was diagnosed in 18.2%, secondary hemorrhage in 18.2%, seizures in 27.3% of patients. One patient died postoperatively with refractory coagulopathy. Conversion to ventriculoperitoneal shunt at six-month follow up was 8/11 (72.7%), with 50% one-year revision-free shunt survival. No patients required a multi-catheter system. Rates of comorbidities and shunt dependency showed very strong positive correlations, hyaline membrane disease rate (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.950), necrotizing enterocolitis (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.999) and persistent ductus arteriosus (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.975). Prematurity and shunt dependency showed a moderate to strong negative correlation, GA (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.527) and BW (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.344).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eExtreme prematurity and comorbidities are associated with increased shunt dependency. However, NEL may decrease the development of complex multi-lobulated hydrocephalus and the need for future shunt revisions. Larger, long-term studies are needed to define optimal timing and criteria for NEL and its benefits and impact on neurodevelopment in this fragile population.\u003c/p\u003e","manuscriptTitle":"Neuroendoscopic Lavage: a single-center retrospective cohort in in the United States","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-27 06:09:11","doi":"10.21203/rs.3.rs-6960828/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-28T20:46:17+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-26T19:56:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"248276932995941794651554664153932591916","date":"2025-08-19T06:31:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"204524430333309740176812569053623542557","date":"2025-08-16T10:58:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-16T08:52:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-27T03:58:59+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-27T03:58:53+00:00","index":"","fulltext":""},{"type":"submitted","content":"Child's Nervous System","date":"2025-06-24T02:40:58+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"childs-nervous-system","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cnsy","sideBox":"Learn more about [Child's Nervous System](http://link.springer.com/journal/381)","snPcode":"381","submissionUrl":"https://submission.nature.com/new-submission/381/3","title":"Child's Nervous System","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"179e9cd2-95da-480d-bd72-bb1fad6fcf9e","owner":[],"postedDate":"August 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-17T16:07:27+00:00","versionOfRecord":{"articleIdentity":"rs-6960828","link":"https://doi.org/10.1007/s00381-025-06994-z","journal":{"identity":"childs-nervous-system","isVorOnly":false,"title":"Child's Nervous System"},"publishedOn":"2025-11-13 15:56:57","publishedOnDateReadable":"November 13th, 2025"},"versionCreatedAt":"2025-08-27 06:09:11","video":"","vorDoi":"10.1007/s00381-025-06994-z","vorDoiUrl":"https://doi.org/10.1007/s00381-025-06994-z","workflowStages":[]},"version":"v1","identity":"rs-6960828","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6960828","identity":"rs-6960828","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}