Splenic vein diameter/portal vein diameter ratio as a predictor of portal vein thrombosis after laparoscopic splenectomy in children

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Methods Patients who underwent LS between September 2014 and August 2024 were retrospectively reviewed. Preoperative and intraoperative clinical data were compared between those with and without PVT. The splenic vein diameter (SVD) was measured at 2, 4, and 6 cm from the portal vein (PV) junction using preoperative transaxial computed tomography images. Results Among 21 patients who underwent LS, those with PVT were significantly older, more likely to be female, and had a higher body mass index. Although splenic maximum diameter, PV diameter, and the spleen volume/standard spleen volume ratio showed no significant differences, SVD was significantly larger at all measured locations in patients with PVT. Additionally, the SVD/portal vein diameter (PVD) ratio was significantly higher at all measured locations in these patients. Receiver operating characteristic analysis identified the SVD/PVD ratio as the most reliable predictor of PVT development, with an optimal cutoff value of 0.7. Conclusion An SVD/PVD ratio ≥ 0.7 is a strong predictor of PVT after LS in children. Measuring this ratio preoperatively may identify high-risk patients, allowing for closer monitoring and potential preventive interventions to reduce PVT incidence. Portal vein thrombosis Laparoscopic splenectomy Splenic vein Risk factor SVD/PVD ratio Figures Figure 1 Figure 2 Introduction Laparoscopic splenectomy (LS), first reported by Delaitre et al. in 1992 [ 1 ] and introduced in pediatric surgery by Tulman et al. in 1993 [ 2 ], is the standard approach for elective splenectomy in children with hereditary spherocytosis, idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, and portal hypertension. LS is widely considered safe and effective, offering shorter hospital stays and lower complication rates, except in patients with extreme splenomegaly [ 3 – 6 ]. However, portal vein thrombosis (PVT) has been a known postoperative complication following splenectomy. Delatour et al. [ 7 ] reported that PVT was among the most common and serious complications following splenectomy. Generally, PVT includes thrombosis of the portal trunk; the left and right branches of the portal vein; and the splenic, superior mesenteric, and inferior mesenteric veins. Despite rarely affecting the prognosis of pediatric patients, PVT can cause fever, abdominal pain, nausea, vomiting, and ileus, depending on the location and thrombus extent. Moreover, severe PVT can lead to ascites, reduced hepatic blood flow, and notable impairment of liver function [ 8 ]. Additionally, the accumulation of pooled blood can induce extensive intestinal necrosis [ 7 , 9 ]. Reported risk factors for PVT include pneumoperitoneum, low preoperative platelet count, and splenomegaly [ 9 ]. Compared to conventional open surgery, LS has been associated with increased incidence rates of PVT, with studies reporting rates exceeding 50% [ 10 ]. The splenic vein diameter (SVD) has been linked to hemodynamic changes in the portal venous system, excluding cases of portal hypertension, and may serve as a more practical PVT predictor compared with spleen weight [ 10 , 11 ]. Notably, applying adult criteria to children is challenging owing to substantial body size differences. Therefore, risk factors for PVT after LS in pediatric patients remain poorly understood. Thus, the present study aimed to identify PVT risk factors after LS in children and determine reliable predictors applicable to pediatric patients. Patients and Methods Data collection This retrospective study included 21 patients who underwent LS between January 2014 and December 2024. Preoperative and intraoperative parameters, including age, sex, diagnosis, preoperative platelet count, preoperative white blood cell count, preoperative prothrombin time, preoperative albumin levels, preoperative total bilirubin content, operative time, intraoperative blood loss, spleen volume, and SVD, were analyzed for their predictive value in PVT. SVD was measured as the ventrodorsal distance at the left end of the abdominal aorta on transverse contrast-enhanced helical computed tomography (CT) images. It was recorded at the splenic vein (SV)–PV junction and at 2-, 4-, and 6-cm distal to the junction, following the method described by Danno et al. [ 11 ]. As reported in our previous study [ 12 ], spleen volume was measured from CT images using three-dimensional image-processing software (SYNAPSE VINCENT, Fujifilm Medical, Japan). The estimated spleen volume was analyzed relative to the standard spleen volume (SSV), calculated as SSV (cm 3 ) = 0.7 + [4.6 × body weight (kg)] [ 13 ]. Given the pediatric population, the spleen volume/SSV ratio was used to account for differences in patient body size. SVD and spleen volume were measured by two pediatric surgical specialists, and the average of their measurements was used. Detection and diagnosis of PVT All 21 patients underwent preoperative and postoperative helical CT with intravenous contrast. Imaging was analyzed prospectively before surgery and between postoperative day (POD) 3 and POD 15 (median: POD 7). PVT was diagnosed when an unenhanced region appeared in the portal system, which had no abnormalities on preoperative CT scans. Compression stockings or an intermittent pneumatic foot pump was used perioperatively for deep venous thrombosis prophylaxis, but no patients received preventive anticoagulation. Statistical analysis All values were expressed as medians and interquartile ranges. Group comparisons were conducted using the Mann–Whitney U test and Fisher’s exact test. The discriminative ability of models was assessed using receiver operating characteristic (ROC) curve analysis, with the area under the curve (AUC) as the evaluation metric. The optimal cutoff values were determined using the Youden index, and sensitivity and specificity were calculated according to these values. Logistic regression analysis was performed to adjust for potential confounders. Statistical analyses were conducted using R software (version 4.3.2; https://www.r-project.org , accessed on October 31, 2023), with significance set at p < 0.05. Ethical approval of the study protocol This retrospective study adhered to the Ethical Guidelines for Clinical Research published by the Ministry of Health, Labor, and Welfare of Japan on July 30, 2003 (revised 2008) and complied with the 1964 Declaration of Helsinki (revised 2008). Informed consent was obtained from all participants. This study was approved by the Ethics Committee of Kyushu University (Institutional Review Board approval number: 24278). Results Indications for splenectomy included hereditary spherocytosis (17 cases), idiopathic thrombocytopenic purpura (2 cases), splenic lymphangioma (1 case), and splenic abscess (1 case). Among the 21 patients, 7 (33.3%) were diagnosed with PVT. Specifically, one patient had > 50% occlusion of the main PV trunk, one had occlusion of the right branch of the PV, and the remaining five had occlusion of the intrahepatic PV. All 7 patients with PVT received systemic therapeutic anticoagulation and underwent contrast-enhanced CT at 1 and 3 months postoperatively. PVT resolved in all seven patients within 3 months after surgery. None of the 21 patients in the present study required treatment for major postoperative complications other than systemic therapeutic anticoagulation. Table 1 shows the perioperative and intraoperative clinical characteristics of patients with and without PVT after LS. Compared with the non-PVT group, the PVT group was significantly older, contained a higher proportion of females, and had a significantly higher body mass index (BMI; p = 0.034, 0.016, and 0.003, respectively). There were no significant differences in preoperative white cell count, preoperative platelet count, preoperative albumin levels, preoperative blood urea nitrogen content, or preoperative prothrombin time between the PVT and non-PVT groups (p = 0.117, 0.709, 0.940, 0.820, and 0.765, respectively). Additionally, no significant differences were found in splenic maximum diameter, portal vein diameter (PVD), and spleen volume/SSV ratio (p = 0.563, 0.477, and 1, respectively). Table 1 Perioperative and intraoperative clinical characteristics of patients with and without PVT after LS Overall (n = 21) PVT group (n = 7) non-PVT group (n = 14) P value Age, years (median [IQR]) 12.0 [11.0, 14.0] 13.0 [12.5, 15.0] 11.5 [11.0, 12.0] 0.034 Gender 0.016 Male (%) 12 (57.1%) 1 (14.3%) 11 (78.6%) Female (%) 9 (42.9%) 6 (85.7%) 3 (21.4%) BMI (median [IQR]) 18.4 [16.6, 20.4] 21.6 [20.8, 22.6] 18.0 [15.3, 18.9] 0.003 BSA, m 2 (median [IQR]) 1.4 [1.1, 1.4] 1.4 [1.3, 1.5] 1.2 [1.0, 1.4] 0.073 White blood cell count (median [IQR]) 7.4 [5.9, 8.4] 8.4 [7.6, 8.6] 6.3 [5.4, 7.9] 0.117 Hemoglobin level (median [IQR]) 11.4 [10.6, 12.1] 11.1 [9.7, 11.2] 11.9 [10.9, 12.5] 0.048 Platelet count (median [IQR]) 267.0 [211.0, 314.0] 267.0 [225.0, 287.5] 271.0 [204.0, 353.5] 0.709 Albumin level (median [IQR]) 4.8 [4.6, 4.9] 4.8 [4.7, 4.8] 4.8 [4.4, 4.9] 0.94 Blood urea nitrogen level (median [IQR]) 11.0 [10.0, 13.0] 11.0 [11.0, 13.0] 11.0 [10.0, 13.0] 0.82 Prothrombin time (median [IQR]) 75.0 [71.0, 81.0] 78.0 [70.5, 79.5] 74.0 [71.2, 81.8] 0.765 Activated partial thromboplastin time (median [IQR]) 36.7 [33.2, 38.7] 34.2 [32.3, 36.5] 37.2 [35.2, 39.6] 0.062 Operating time (median [IQR]) 197.0 [159.0, 285.0] 163.0 [127.0, 213.0] 257.5 [164.5, 293.2] 0.205 Insufflation time (median [IQR]) 106.0 [81.0, 155.0] 85.0 [69.0, 128.0] 109.0 [87.8, 157.2] 0.412 Intraoperative blood loss per BSA (median [IQR]) 39.3 [3.1, 82.0] 3.8 [0.7, 117.7] 39.5 [9.3, 62.7] 0.663 Intraoperative infusion volume per BSA (median [IQR]) 1047.4 [891.8, 1206.5] 865.5 [772.4, 917.7] 1160.8 [1034.9, 1276.6] 0.044 Postoperative maximum platelet count (median [IQR]) 894.0 [749.8, 1123.8] 970.0 [842.0, 1118.0] 879.0 [744.0, 1122.0] 0.405 Rate of postoperative platelet count increase (median [IQR]) 3.6 [2.5, 4.1] 4.1 [3.6, 4.3] 2.9 [2.2, 3.9] 0.122 Spleen longitudinal diameter, mm (median [IQR]) 131.0 [116.5, 152.8] 134.5 [119.0, 155.2] 130.5 [117.2, 150.8] 0.563 SMVD (median [IQR]) 8.6 [8.4, 8.8] 8.5 [8.4, 8.6] 8.6 [8.4, 8.8] 0.5 PVD (median [IQR]) 11.3 [10.9, 12.4] 11.3 [11.1, 12.4] 11.3 [10.7, 12.2] 0.477 SVD, at the junction (median [IQR]) 7.8 [6.8, 8.8] 8.8 [8.2, 9.2] 7.0 [6.4, 7.8] 0.014 SVD, 2 cm from the junction (median [IQR]) 6.6 [6.0, 8.2] 8.3 [8.2, 8.8] 6.2 [5.9, 6.6] 0.005 SVD, 4 cm from the junction(median [IQR]) 5.8 [5.4, 8.6] 9.6 [8.0, 10.0] 5.6 [5.3, 5.8] 0.003 SVD, 6 cm from the junction(median [IQR]) 6.7 [6.0, 8.4] 9.5 [8.6, 10.6] 6.2 [5.5, 6.7] 0.001 SVD/PVD, at the junction(median [IQR]) 0.7 [0.6, 0.7] 0.7 [0.7, 0.8] 0.6 [0.6, 0.7] 0.017 SVD/PVD, 2 cm from the junction(median [IQR]) 0.6 [0.5, 0.7] 0.7 [0.7, 0.8] 0.6 [0.5, 0.6] 0.014 SVD/PVD, 4 cm from the junction(median [IQR]) 0.6 [0.5, 0.7] 0.7 [0.7, 0.9] 0.5 [0.5, 0.6] 0.003 SVD/PVD, 6 cm from the junction(median [IQR]) 0.6 [0.5, 0.7] 0.8 [0.7, 0.9] 0.5 [0.5, 0.6] 0.001 Spleen volume, cm 3 (median [IQR]) 369.0 [290.0, 562.0] 400.0 [344.0, 613.5] 303.5 [264.5, 463.2] 0.172 SSV, cm 3 (median [IQR]) 206.3 [145.6, 222.4] 221.0 [213.2, 254.6] 176.9 [129.4, 211.5] 0.03 Spleen volume /SSV ratio (median [IQR]) 2.1 [1.5, 2.4] 2.1 [1.5, 2.5] 2.1 [1.5, 2.4] 1 PVT: portal vein thrombosis; LS: laparoscopic splenectomy; IQR: interquartile range; BMI: body mass index; BSA; body surface area, SMVD; superior mesenteric vein diameter, PVD; portal vein diameter, SVD; splenic vein diameter,SSV; standard spleen volume. Preoperative SVD at the junction and 2-, 4-, and 6-cm distal from the junction was significantly larger in patients with PVT relative to those without PVT (p = 0.014, 0.005, 0.003, and 0.001, respectively; Fig. 1 a). Similarly, the preoperative SVD/PVD ratio at the junction and 2-, 4-, and 6-cm distal from the junction was significantly higher in patients with PVT (p = 0.017, 0.004, 0.003, and 0.001, respectively; Fig. 1 b). Between the patient groups, the most significant differences in SVD and the SVD/PVD ratio were observed at the 6-cm site (both p = 0.001). In terms of intraoperative characteristics, there were no significant differences in operating time, insufflation times, or intraoperative blood loss per body surface area (p = 0.205, 0.412, and 0.663, respectively). However, the intraoperative infusion volume per body surface area in the non-PVT group was significantly greater than that in the PVT group (p = 0.044). In terms of postoperative characteristics, there were no significant differences in postoperative maximum platelet count, and the rate of postoperative platelet count increased (p = 0.405, 0.122). To determine the optimal cutoff value for SVD as a predictor of PVT, ROC analysis was performed. In this analysis, the AUC was 0.949 [95% confidence interval (CI) 0.862–1.000], with an optimum cutoff value of 7.1 (sensitivity: 1.0; specificity: 0.786; Fig. 2 a). A similar ROC analysis was performed for the SVD/PVD ratio as a predictor of PVT: the AUC was 0.969 (95% CI: 0.903–1.000), with an optimum cutoff value of 0.7 (sensitivity: 1.0; specificity 0.929; Fig. 2 b). The AUC of the SVD/PVD ratio was higher than that of the SVD, indicating the ratio’s superior predictive and diagnostic ability for PVT. To identify the independent risk factors for PVT development after LS, a multivariate logistic regression analysis was performed (Table 2 ). Three clinical characteristics, namely age, BMI, and SVD/PVD ratio, showed significant differences between the PVT and non-PVT groups and were considered candidate predictors. Further analysis results indicated that the SVD/PVD ratio was the most useful predictor of PVT development (odds ratio = 27.354%, CI 1.100–680.280, p = 0.044). Table 2 ROC analysis identifying a predictive factor for PVT Parameters AUC (95% CI) Threshold Sensitivity Specificity SVD, at the junction 0.837 (0.662–1) 7.95 0.857 0.786 SVD, 2 cm from the junction 0.888 (0.665–1) 7.7 0.857 1 SVD, 4 cm from the junction 0.908 (0.781–1) 6 1 0.786 SVD, 6 cm from the junction 0.949 (0.862–1) 7.1 1 0.786 SVD/PVD, at the junction 0.827 (0.646–1) 0.652 1 0.643 SVD/PVD, 2 cm from the junction 0.837 (0.604–1) 0.684 0.714 1 SVD/PVD, 4 cm from the junction 0.908 (0.78–1) 0.673 0.857 0.857 SVD/PVD, 6 cm from the junction 0.969 (0.903–1) 0.68 1 0.929 ROC: receiver operating characteristic; PVT: portal vein thrombosis; AUC: area under the curve; CI: confidence interval; SVD: splenic vein diameter; PVD: portal vein diameter. Table 3 Multivariate logistic regression analysis of independent risk factors for PVT development after LS. Parameters OR (95% CI) P value Age, years > 12 1.465 (0.034–62.502) 0.842 BMI > 20 7.304 (0.168–318.109) 0.302 SVD/PVD ratio, 6 cm from the junction, ≥ 0.7 27.354 (1.100–680.280) 0.044 OR: odds ratio; PVT: portal vein thrombosis; LS: laparoscopic splenectomy; BMI: body mass index; SVD/PVD: splenic vein diameter/portal vein diameter Discussion PVT has been considered one of the most critical complications following splenectomy. However, up to 50% of PVT cases remain asymptomatic. Moreover, when symptoms do occur, they are often nonspecific, including abdominal pain, inflammatory responses, and elevated liver enzymes, which complicates clinical diagnosis [ 9 , 14 ]. In the present study, none of the seven patients with PVT exhibited specific symptoms, with all cases been detected via postoperative ultrasound or CT scans, confirming the importance of appropriate imaging studies during postoperative evaluation after LS. Several risk factors for PVT development have been identified, including splenomegaly and low preoperative platelet counts [ 9 ]. Female sex has also been suggested as risk factor in children. In our study, the proportion of female patients was significantly higher in the PVT group, aligning with previous findings. Soyer et al. [ 15 ] proposed that endogenous estrogen activity may increase susceptibility to deep vein thrombosis [ 15 ]. However, whether this association is causal or incidental remains unclear, and further research is needed to clarify this relationship. Splenomegaly and an increase in postoperative platelet count have also been considered a key risk factor for PVT after splenectomy [ 9 , 16 17 ]. However, in this study, no significant difference in splenic size was observed between the PVT and non-PVT groups. This may be because most patients in our cohort had splenomegaly due to hereditary spherocytosis, reducing variability in spleen size. Additionally, no significant differences in the postoperative platelet count increase had been noted. Several reports suggest that LS is associated with a higher incidence of PVT compared with conventional open splenectomy [ 14 , 18 ]. One proposed mechanism is circulatory insufficiency in the portal system due to pneumoperitoneum, which may contribute to PVT development after LS. However, we observed no significant differences in operation time or insufflation time between the PVT and non-PVT groups. This likely reflects the study’s single-institution design, where pneumoperitoneum pressure and flow rate were standardized. Nevertheless, LS has been reported to have a PVT incidence exceeding 50%, higher than that of open surgery [ 10 , 14 , 18 ]. Although PVT after splenectomy is rarely reported to impact patient prognosis, it can impair liver function and requires appropriate prevention. We also found that intraoperative infusion volume per body surface area was significantly greater in the non-PVT group than in the PVT group. After splenectomy, SV flow decreases, leading to a reduction in SVD, which promotes PVT development. Sufficient intraoperative fluid administration may help maintain SV flow velocity after splenectomy and prevent thrombosis formation in the SV. Studies have shown that SVD is directly related to hemodynamic changes in the portal venous system, excluding patients with portal hypertension, making it a more practical predictor of PVT compared with spleen weight [ 10 , 11 ]. Kuroki et al. [ 10 ] suggested that a dilated SV may contribute to PVT after LS due to decreased blood flow, blood stasis, and blood turbulence, identifying a SVD greater than 10 mm as a highly sensitive and specific predictor of PVT. Danno et al. [ 11 ] proposed that a greater reduction in SVD correlates with a higher PVT incidence after LS and reported that a preoperative SVD of 8 mm at 2-, 4-, and 6-cm distal from the splenoportal junction serves as an optimal predictor of PVT. Evaluating preoperative SVD via enhanced CT is useful for identifying patients at high risk of developing PVT after LS. However, applying adult criteria to children is challenging, given the marked differences in body size among cases. To addresses this, we focused on the SVD/PVD ratio rather than the absolute SVD to establish a more size-adjusted reference value for children. The first key finding in this study was that measurements taken 6-cm distal from the junction provided more accurate predictive values than those taken at the junction, based on Mann–Whitney U test results and AUC values. The second key finding was that using the SVD/PVD ratio rather than absolute SVD resulted in a higher AUC, making it a more effective predictor. Moreover, we identified 0.7 as the optimal SVD/PVD ratio cutoff for predicting PVT after LS. This study has several limitations. First, the sample size was relatively small. Second, it was a retrospective, single-center study. Therefore, a detailed analysis of the total amount of perioperative infusion volume was difficult. Third, patients in the non-PVT group were significantly younger than those in the PVT group. Therefore, differences in disease duration leading to splenectomy may have influenced susceptibility to thrombus formation. Future prospective, multicenter studies with larger cohorts are required to validate these findings. Additionally, a standardized thromboprophylaxis protocol based on the SVD/PVD ratio cutoff value should be developed. Conclusion This study demonstrated that older age, higher BMI, female sex, and broader SVD are associated with an increased risk of PVT following LS in children. Identifying these risk factors allows for early screening of high-risk individuals, enabling preventive measures and optimized postoperative care. The SVD/PVD ratio (≥ 0.7) proved to be a strong predictor of PVT, offering a useful parameter for risk assessment. It is expected that preoperative evaluation of PVT risk and intraoperative fluid management strategies based on these findings may help prevent PVT development, improving patient outcomes after LS. Declarations Acknowledgments We thank Enago (https://www.enago.jp/) for editing a draft of this manuscript. We are grateful to Eiji Sadashima (Department of Medical Research Institute, Saga-Ken Medical Center Koseikan, Saga, Japan) for his contribution to the statistical analyses. Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Competing interests: The authors declare no conflicts of interest in association with the present study. Ethical approval: This study was performed in accordance with the Ethical Guidelines for Clinical Research published by the Ministry of Health, Labour and Welfare of Japan on July 30, 2003 (revised in 2008) and complied with the Declaration of Helsinki (revised in 2008). The Ethics Committee for Clinical Research of Kyushu University Hospital approved this study (No. 24278). Authors’ contributions: Atsuhisa Fukuta: designed research/study, performed research/study, analyzed data, and wrote the paper. Toshiharu Matsuura: collected data and revised the manuscript. Yasuyuki Uchida: collected data. Naonori Kawakubo: collected data. Takuya Kondo: collected data. Yoshiaki Takahashi: collected data. Koichiro Yoshimaru: collected data. Kouji Nagata: collected data, Tatsuro Tajiri: revised the manuscript. All authors reviewed the manuscript. Consent to participate Informed consent was obtained from all patients’ guardians. 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Cite Share Download PDF Status: Published Journal Publication published 29 Aug, 2025 Read the published version in Pediatric Surgery International → Version 1 posted Editorial decision: Accepted 17 Aug, 2025 Reviews received at journal 17 Aug, 2025 Reviewers agreed at journal 17 Aug, 2025 Reviewers invited by journal 17 Aug, 2025 Editor assigned by journal 09 Aug, 2025 Submission checks completed at journal 08 Aug, 2025 First submitted to journal 04 Aug, 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. 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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-7291537","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":501442391,"identity":"7edaa4c1-b027-465b-a399-c45d015705c5","order_by":0,"name":"Atsuhisa Fukuta","email":"data:image/png;base64,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","orcid":"","institution":"Kyushu University","correspondingAuthor":true,"prefix":"","firstName":"Atsuhisa","middleName":"","lastName":"Fukuta","suffix":""},{"id":501442392,"identity":"09ef4348-c52f-4a1b-8fe3-5103c2b926be","order_by":1,"name":"Toshiharu Matsuura","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Toshiharu","middleName":"","lastName":"Matsuura","suffix":""},{"id":501442393,"identity":"6833ff8c-e521-479c-abb6-9f99453a732f","order_by":2,"name":"Yasuyuki Uchida","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Yasuyuki","middleName":"","lastName":"Uchida","suffix":""},{"id":501442394,"identity":"fec7ff61-bfea-4244-ac01-bef3f0bc182c","order_by":3,"name":"Naonori Kawakubo","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Naonori","middleName":"","lastName":"Kawakubo","suffix":""},{"id":501442395,"identity":"db767675-79a8-4e11-9a0f-9544636a1b3d","order_by":4,"name":"Takuya Kondo","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Takuya","middleName":"","lastName":"Kondo","suffix":""},{"id":501442396,"identity":"f22c89b6-66c7-48e7-8ccd-2dfe51045fa3","order_by":5,"name":"Yoshiaki Takahashi","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Yoshiaki","middleName":"","lastName":"Takahashi","suffix":""},{"id":501442397,"identity":"5ca859f9-6aa5-462f-b31b-c1eef8f7c386","order_by":6,"name":"Koichiro Yoshimaru","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Koichiro","middleName":"","lastName":"Yoshimaru","suffix":""},{"id":501442398,"identity":"158e3009-898a-45a0-a0d1-53186bdad4f0","order_by":7,"name":"Kouji Nagata","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Kouji","middleName":"","lastName":"Nagata","suffix":""},{"id":501442399,"identity":"185229a0-8a88-469a-8581-d2375ff2a61b","order_by":8,"name":"Tatsuro Tajiri","email":"","orcid":"","institution":"Kyushu University","correspondingAuthor":false,"prefix":"","firstName":"Tatsuro","middleName":"","lastName":"Tajiri","suffix":""}],"badges":[],"createdAt":"2025-08-04 13:08:39","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7291537/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7291537/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00383-025-06171-y","type":"published","date":"2025-08-29T15:57:53+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":89979876,"identity":"3516391d-9d1c-41a9-823d-26c4acbae79f","added_by":"auto","created_at":"2025-08-27 06:20:39","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":50424,"visible":true,"origin":"","legend":"\u003cp\u003eBox-and-whisker plots of preoperative SVD and SVD/PVD ratio at the junction and at 2-, 4-, and 6-cm distal from the junction in patients with and without PVT.\u003c/p\u003e\n\u003cp\u003e(a) SVD was significantly greater at all measured locations in patients with PVT (p = 0.014, 0.005, 0.003, and 0.001, respectively).\u003c/p\u003e\n\u003cp\u003e(b) SVD/PVD ratio was significantly greater at all measured locations in patients with PVT (p = 0.017, 0.004, 0.003, and 0.001, respectively)\u003c/p\u003e","description":"","filename":"Fig1a.png","url":"https://assets-eu.researchsquare.com/files/rs-7291537/v1/7f2483bc2f4932dcf1408683.png"},{"id":89982271,"identity":"e21459f4-7f7d-4c0c-9428-c5ac5473f459","added_by":"auto","created_at":"2025-08-27 06:28:39","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":110386,"visible":true,"origin":"","legend":"\u003cp\u003eROC analysis assessing the predictive value of SVD and the SVD/PVD ratio for PVT.\u003c/p\u003e\n\u003cp\u003e(a) Area under the ROC curve was 0.949 (95% CI: 0.862–1.000), with an optimal cutoff value of 7.1 (sensitivity: 1.0; specificity: 0.786).\u003c/p\u003e\n\u003cp\u003e(b) Area under the ROC curve was 0.969 (95% CI: 0.903–1.000), with an optimal cutoff value of 0.7 (sensitivity: 1.0; specificity: 0.929)\u003c/p\u003e","description":"","filename":"Fig2a.png","url":"https://assets-eu.researchsquare.com/files/rs-7291537/v1/cc8def86f00debcea2f16819.png"},{"id":90345207,"identity":"aa2631d2-8206-439f-8b03-d66b681d6c45","added_by":"auto","created_at":"2025-09-01 16:10:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":8352547,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7291537/v1/2fcb9829-7c31-4048-9ca3-94a8e6066747.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Splenic vein diameter/portal vein diameter ratio as a predictor of portal vein thrombosis after laparoscopic splenectomy in children","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLaparoscopic splenectomy (LS), first reported by Delaitre et al. in 1992 [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] and introduced in pediatric surgery by Tulman et al. in 1993 [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], is the standard approach for elective splenectomy in children with hereditary spherocytosis, idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, and portal hypertension. LS is widely considered safe and effective, offering shorter hospital stays and lower complication rates, except in patients with extreme splenomegaly [\u003cspan additionalcitationids=\"CR4 CR5\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e–\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. However, portal vein thrombosis (PVT) has been a known postoperative complication following splenectomy.\u003c/p\u003e\u003cp\u003eDelatour et al. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] reported that PVT was among the most common and serious complications following splenectomy. Generally, PVT includes thrombosis of the portal trunk; the left and right branches of the portal vein; and the splenic, superior mesenteric, and inferior mesenteric veins. Despite rarely affecting the prognosis of pediatric patients, PVT can cause fever, abdominal pain, nausea, vomiting, and ileus, depending on the location and thrombus extent. Moreover, severe PVT can lead to ascites, reduced hepatic blood flow, and notable impairment of liver function [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Additionally, the accumulation of pooled blood can induce extensive intestinal necrosis [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Reported risk factors for PVT include pneumoperitoneum, low preoperative platelet count, and splenomegaly [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Compared to conventional open surgery, LS has been associated with increased incidence rates of PVT, with studies reporting rates exceeding 50% [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe splenic vein diameter (SVD) has been linked to hemodynamic changes in the portal venous system, excluding cases of portal hypertension, and may serve as a more practical PVT predictor compared with spleen weight [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Notably, applying adult criteria to children is challenging owing to substantial body size differences. Therefore, risk factors for PVT after LS in pediatric patients remain poorly understood. Thus, the present study aimed to identify PVT risk factors after LS in children and determine reliable predictors applicable to pediatric patients.\u003c/p\u003e"},{"header":"Patients and Methods","content":"\u003cp\u003e\u003cb\u003eData collection\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThis retrospective study included 21 patients who underwent LS between January 2014 and December 2024. Preoperative and intraoperative parameters, including age, sex, diagnosis, preoperative platelet count, preoperative white blood cell count, preoperative prothrombin time, preoperative albumin levels, preoperative total bilirubin content, operative time, intraoperative blood loss, spleen volume, and SVD, were analyzed for their predictive value in PVT.\u003c/p\u003e\u003cp\u003eSVD was measured as the ventrodorsal distance at the left end of the abdominal aorta on transverse contrast-enhanced helical computed tomography (CT) images. It was recorded at the splenic vein (SV)–PV junction and at 2-, 4-, and 6-cm distal to the junction, following the method described by Danno et al. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. As reported in our previous study [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], spleen volume was measured from CT images using three-dimensional image-processing software (SYNAPSE VINCENT, Fujifilm Medical, Japan). The estimated spleen volume was analyzed relative to the standard spleen volume (SSV), calculated as SSV (cm\u003csup\u003e3\u003c/sup\u003e) = 0.7 + [4.6 × body weight (kg)] [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Given the pediatric population, the spleen volume/SSV ratio was used to account for differences in patient body size. SVD and spleen volume were measured by two pediatric surgical specialists, and the average of their measurements was used.\u003c/p\u003e\u003cp\u003e\u003cb\u003eDetection and diagnosis of PVT\u003c/b\u003e\u003c/p\u003e\u003cp\u003eAll 21 patients underwent preoperative and postoperative helical CT with intravenous contrast. Imaging was analyzed prospectively before surgery and between postoperative day (POD) 3 and POD 15 (median: POD 7). PVT was diagnosed when an unenhanced region appeared in the portal system, which had no abnormalities on preoperative CT scans. Compression stockings or an intermittent pneumatic foot pump was used perioperatively for deep venous thrombosis prophylaxis, but no patients received preventive anticoagulation.\u003c/p\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eAll values were expressed as medians and interquartile ranges. Group comparisons were conducted using the Mann–Whitney U test and Fisher’s exact test. The discriminative ability of models was assessed using receiver operating characteristic (ROC) curve analysis, with the area under the curve (AUC) as the evaluation metric. The optimal cutoff values were determined using the Youden index, and sensitivity and specificity were calculated according to these values. Logistic regression analysis was performed to adjust for potential confounders. Statistical analyses were conducted using R software (version 4.3.2; \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.r-project.org\u003c/span\u003e\u003cspan address=\"https://www.r-project.org\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e, accessed on October 31, 2023), with significance set at p \u0026lt; 0.05.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eEthical approval of the study protocol\u003c/b\u003e\u003c/p\u003e\u003cp\u003e This retrospective study adhered to the Ethical Guidelines for Clinical Research published by the Ministry of Health, Labor, and Welfare of Japan on July 30, 2003 (revised 2008) and complied with the 1964 Declaration of Helsinki (revised 2008). Informed consent was obtained from all participants. This study was approved by the Ethics Committee of Kyushu University (Institutional Review Board approval number: 24278).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIndications for splenectomy included hereditary spherocytosis (17 cases), idiopathic thrombocytopenic purpura (2 cases), splenic lymphangioma (1 case), and splenic abscess (1 case). Among the 21 patients, 7 (33.3%) were diagnosed with PVT. Specifically, one patient had\u0026thinsp;\u0026gt;\u0026thinsp;50% occlusion of the main PV trunk, one had occlusion of the right branch of the PV, and the remaining five had occlusion of the intrahepatic PV. All 7 patients with PVT received systemic therapeutic anticoagulation and underwent contrast-enhanced CT at 1 and 3 months postoperatively. PVT resolved in all seven patients within 3 months after surgery. None of the 21 patients in the present study required treatment for major postoperative complications other than systemic therapeutic anticoagulation.\u003c/p\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the perioperative and intraoperative clinical characteristics of patients with and without PVT after LS. Compared with the non-PVT group, the PVT group was significantly older, contained a higher proportion of females, and had a significantly higher body mass index (BMI; p\u0026thinsp;=\u0026thinsp;0.034, 0.016, and 0.003, respectively). There were no significant differences in preoperative white cell count, preoperative platelet count, preoperative albumin levels, preoperative blood urea nitrogen content, or preoperative prothrombin time between the PVT and non-PVT groups (p\u0026thinsp;=\u0026thinsp;0.117, 0.709, 0.940, 0.820, and 0.765, respectively). Additionally, no significant differences were found in splenic maximum diameter, portal vein diameter (PVD), and spleen volume/SSV ratio (p\u0026thinsp;=\u0026thinsp;0.563, 0.477, and 1, respectively).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePerioperative and intraoperative clinical characteristics of patients with and without PVT after LS\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOverall\u003c/p\u003e\u003cp\u003e(n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePVT group\u003c/p\u003e\u003cp\u003e(n\u0026thinsp;=\u0026thinsp;7)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003enon-PVT group\u003c/p\u003e\u003cp\u003e(n\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eP value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge, years (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12.0 [11.0, 14.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e13.0 [12.5, 15.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.5 [11.0, 12.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.034\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.016\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12 (57.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1 (14.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11 (78.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9 (42.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6 (85.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e3 (21.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e18.4 [16.6, 20.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e21.6 [20.8, 22.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e18.0 [15.3, 18.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBSA, m\u003csup\u003e2\u003c/sup\u003e (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1.4 [1.1, 1.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.4 [1.3, 1.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1.2 [1.0, 1.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.073\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWhite blood cell count (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7.4 [5.9, 8.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.4 [7.6, 8.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e6.3 [5.4, 7.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.117\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHemoglobin level (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11.4 [10.6, 12.1]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11.1 [9.7, 11.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.9 [10.9, 12.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.048\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePlatelet count (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e267.0 [211.0, 314.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e267.0 [225.0, 287.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e271.0 [204.0, 353.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.709\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAlbumin level (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e4.8 [4.6, 4.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4.8 [4.7, 4.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e4.8 [4.4, 4.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.94\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBlood urea nitrogen level (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11.0 [10.0, 13.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11.0 [11.0, 13.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.0 [10.0, 13.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.82\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProthrombin time (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e75.0 [71.0, 81.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e78.0 [70.5, 79.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e74.0 [71.2, 81.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.765\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eActivated partial thromboplastin time (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e36.7 [33.2, 38.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e34.2 [32.3, 36.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e37.2 [35.2, 39.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.062\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOperating time (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e197.0 [159.0, 285.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e163.0 [127.0, 213.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e257.5 [164.5, 293.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.205\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eInsufflation time (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e106.0 [81.0, 155.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e85.0 [69.0, 128.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e109.0 [87.8, 157.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.412\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIntraoperative blood loss per BSA (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e39.3 [3.1, 82.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3.8 [0.7, 117.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e39.5 [9.3, 62.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.663\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIntraoperative infusion volume per BSA (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1047.4 [891.8, 1206.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e865.5 [772.4, 917.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1160.8 [1034.9, 1276.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.044\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePostoperative maximum platelet count (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e894.0 [749.8, 1123.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e970.0 [842.0, 1118.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e879.0 [744.0, 1122.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.405\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRate of postoperative platelet count increase (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3.6 [2.5, 4.1]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4.1 [3.6, 4.3]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.9 [2.2, 3.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.122\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpleen longitudinal diameter, mm (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e131.0 [116.5, 152.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e134.5 [119.0, 155.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e130.5 [117.2, 150.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.563\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSMVD (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e8.6 [8.4, 8.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.5 [8.4, 8.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e8.6 [8.4, 8.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePVD (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11.3 [10.9, 12.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11.3 [11.1, 12.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.3 [10.7, 12.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.477\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, at the junction (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7.8 [6.8, 8.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.8 [8.2, 9.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e7.0 [6.4, 7.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.014\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, 2 cm from the junction (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6.6 [6.0, 8.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.3 [8.2, 8.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e6.2 [5.9, 6.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.005\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, 4 cm from the junction(median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e5.8 [5.4, 8.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9.6 [8.0, 10.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5.6 [5.3, 5.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, 6 cm from the junction(median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6.7 [6.0, 8.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9.5 [8.6, 10.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e6.2 [5.5, 6.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, at the junction(median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.7 [0.6, 0.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.7 [0.7, 0.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.6 [0.6, 0.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.017\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, 2 cm from the junction(median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.6 [0.5, 0.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.7 [0.7, 0.8]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.6 [0.5, 0.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.014\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, 4 cm from the junction(median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.6 [0.5, 0.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.7 [0.7, 0.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.5 [0.5, 0.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, 6 cm from the junction(median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.6 [0.5, 0.7]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.8 [0.7, 0.9]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.5 [0.5, 0.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpleen volume, cm\u003csup\u003e3\u003c/sup\u003e (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e369.0 [290.0, 562.0]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e400.0 [344.0, 613.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e303.5 [264.5, 463.2]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.172\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSSV, cm\u003csup\u003e3\u003c/sup\u003e (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e206.3 [145.6, 222.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e221.0 [213.2, 254.6]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e176.9 [129.4, 211.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.03\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpleen volume /SSV ratio (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2.1 [1.5, 2.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2.1 [1.5, 2.5]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.1 [1.5, 2.4]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003ePVT: portal vein thrombosis; LS: laparoscopic splenectomy; IQR: interquartile range; BMI: body mass index; BSA; body surface area, SMVD; superior mesenteric vein diameter, PVD; portal vein diameter, SVD; splenic vein diameter,SSV; standard spleen volume.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003ePreoperative SVD at the junction and 2-, 4-, and 6-cm distal from the junction was significantly larger in patients with PVT relative to those without PVT (p\u0026thinsp;=\u0026thinsp;0.014, 0.005, 0.003, and 0.001, respectively; Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea). Similarly, the preoperative SVD/PVD ratio at the junction and 2-, 4-, and 6-cm distal from the junction was significantly higher in patients with PVT (p\u0026thinsp;=\u0026thinsp;0.017, 0.004, 0.003, and 0.001, respectively; Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb). Between the patient groups, the most significant differences in SVD and the SVD/PVD ratio were observed at the 6-cm site (both p\u0026thinsp;=\u0026thinsp;0.001). In terms of intraoperative characteristics, there were no significant differences in operating time, insufflation times, or intraoperative blood loss per body surface area (p\u0026thinsp;=\u0026thinsp;0.205, 0.412, and 0.663, respectively). However, the intraoperative infusion volume per body surface area in the non-PVT group was significantly greater than that in the PVT group (p\u0026thinsp;=\u0026thinsp;0.044). In terms of postoperative characteristics, there were no significant differences in postoperative maximum platelet count, and the rate of postoperative platelet count increased (p\u0026thinsp;=\u0026thinsp;0.405, 0.122).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTo determine the optimal cutoff value for SVD as a predictor of PVT, ROC analysis was performed. In this analysis, the AUC was 0.949 [95% confidence interval (CI) 0.862\u0026ndash;1.000], with an optimum cutoff value of 7.1 (sensitivity: 1.0; specificity: 0.786; Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). A similar ROC analysis was performed for the SVD/PVD ratio as a predictor of PVT: the AUC was 0.969 (95% CI: 0.903\u0026ndash;1.000), with an optimum cutoff value of 0.7 (sensitivity: 1.0; specificity 0.929; Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb). The AUC of the SVD/PVD ratio was higher than that of the SVD, indicating the ratio\u0026rsquo;s superior predictive and diagnostic ability for PVT.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTo identify the independent risk factors for PVT development after LS, a multivariate logistic regression analysis was performed (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Three clinical characteristics, namely age, BMI, and SVD/PVD ratio, showed significant differences between the PVT and non-PVT groups and were considered candidate predictors. Further analysis results indicated that the SVD/PVD ratio was the most useful predictor of PVT development (odds ratio\u0026thinsp;=\u0026thinsp;27.354%, CI 1.100\u0026ndash;680.280, p\u0026thinsp;=\u0026thinsp;0.044).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eROC analysis identifying a predictive factor for PVT\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParameters\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAUC (95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eThreshold\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSensitivity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSpecificity\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, at the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.837 (0.662\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.857\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.786\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, 2 cm from the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.888 (0.665\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.857\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, 4 cm from the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.908 (0.781\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.786\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD, 6 cm from the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.949 (0.862\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.786\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, at the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.827 (0.646\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.652\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.643\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, 2 cm from the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.837 (0.604\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.684\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.714\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, 4 cm from the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.908 (0.78\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.673\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.857\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.857\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD, 6 cm from the junction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.969 (0.903\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.68\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.929\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eROC: receiver operating characteristic; PVT: portal vein thrombosis; AUC: area under the curve; CI: confidence interval; SVD: splenic vein diameter; PVD: portal vein diameter.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMultivariate logistic regression analysis of independent risk factors for PVT development after LS.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParameters\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOR (95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eP value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge, years\u0026thinsp;\u0026gt;\u0026thinsp;12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1.465 (0.034\u0026ndash;62.502)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.842\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI\u0026thinsp;\u0026gt;\u0026thinsp;20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7.304 (0.168\u0026ndash;318.109)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.302\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSVD/PVD ratio, 6 cm from the junction, \u0026ge; 0.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e27.354 (1.100\u0026ndash;680.280)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.044\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"3\"\u003eOR: odds ratio; PVT: portal vein thrombosis; LS: laparoscopic splenectomy; BMI: body mass index; SVD/PVD: splenic vein diameter/portal vein diameter\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003ePVT has been considered one of the most critical complications following splenectomy. However, up to 50% of PVT cases remain asymptomatic. Moreover, when symptoms do occur, they are often nonspecific, including abdominal pain, inflammatory responses, and elevated liver enzymes, which complicates clinical diagnosis [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. In the present study, none of the seven patients with PVT exhibited specific symptoms, with all cases been detected via postoperative ultrasound or CT scans, confirming the importance of appropriate imaging studies during postoperative evaluation after LS.\u003c/p\u003e\u003cp\u003eSeveral risk factors for PVT development have been identified, including splenomegaly and low preoperative platelet counts [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Female sex has also been suggested as risk factor in children. In our study, the proportion of female patients was significantly higher in the PVT group, aligning with previous findings. Soyer et al. [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] proposed that endogenous estrogen activity may increase susceptibility to deep vein thrombosis [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. However, whether this association is causal or incidental remains unclear, and further research is needed to clarify this relationship.\u003c/p\u003e\u003cp\u003eSplenomegaly and an increase in postoperative platelet count have also been considered a key risk factor for PVT after splenectomy [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. However, in this study, no significant difference in splenic size was observed between the PVT and non-PVT groups. This may be because most patients in our cohort had splenomegaly due to hereditary spherocytosis, reducing variability in spleen size. Additionally, no significant differences in the postoperative platelet count increase had been noted.\u003c/p\u003e\u003cp\u003eSeveral reports suggest that LS is associated with a higher incidence of PVT compared with conventional open splenectomy [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. One proposed mechanism is circulatory insufficiency in the portal system due to pneumoperitoneum, which may contribute to PVT development after LS. However, we observed no significant differences in operation time or insufflation time between the PVT and non-PVT groups. This likely reflects the study\u0026rsquo;s single-institution design, where pneumoperitoneum pressure and flow rate were standardized. Nevertheless, LS has been reported to have a PVT incidence exceeding 50%, higher than that of open surgery [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Although PVT after splenectomy is rarely reported to impact patient prognosis, it can impair liver function and requires appropriate prevention.\u003c/p\u003e\u003cp\u003eWe also found that intraoperative infusion volume per body surface area was significantly greater in the non-PVT group than in the PVT group. After splenectomy, SV flow decreases, leading to a reduction in SVD, which promotes PVT development. Sufficient intraoperative fluid administration may help maintain SV flow velocity after splenectomy and prevent thrombosis formation in the SV.\u003c/p\u003e\u003cp\u003eStudies have shown that SVD is directly related to hemodynamic changes in the portal venous system, excluding patients with portal hypertension, making it a more practical predictor of PVT compared with spleen weight [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Kuroki et al. [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] suggested that a dilated SV may contribute to PVT after LS due to decreased blood flow, blood stasis, and blood turbulence, identifying a SVD greater than 10 mm as a highly sensitive and specific predictor of PVT. Danno et al. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] proposed that a greater reduction in SVD correlates with a higher PVT incidence after LS and reported that a preoperative SVD of 8 mm at 2-, 4-, and 6-cm distal from the splenoportal junction serves as an optimal predictor of PVT. Evaluating preoperative SVD via enhanced CT is useful for identifying patients at high risk of developing PVT after LS. However, applying adult criteria to children is challenging, given the marked differences in body size among cases. To addresses this, we focused on the SVD/PVD ratio rather than the absolute SVD to establish a more size-adjusted reference value for children. The first key finding in this study was that measurements taken 6-cm distal from the junction provided more accurate predictive values than those taken at the junction, based on Mann\u0026ndash;Whitney U test results and AUC values. The second key finding was that using the SVD/PVD ratio rather than absolute SVD resulted in a higher AUC, making it a more effective predictor. Moreover, we identified 0.7 as the optimal SVD/PVD ratio cutoff for predicting PVT after LS.\u003c/p\u003e\u003cp\u003eThis study has several limitations. First, the sample size was relatively small. Second, it was a retrospective, single-center study. Therefore, a detailed analysis of the total amount of perioperative infusion volume was difficult. Third, patients in the non-PVT group were significantly younger than those in the PVT group. Therefore, differences in disease duration leading to splenectomy may have influenced susceptibility to thrombus formation. Future prospective, multicenter studies with larger cohorts are required to validate these findings. Additionally, a standardized thromboprophylaxis protocol based on the SVD/PVD ratio cutoff value should be developed.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study demonstrated that older age, higher BMI, female sex, and broader SVD are associated with an increased risk of PVT following LS in children. Identifying these risk factors allows for early screening of high-risk individuals, enabling preventive measures and optimized postoperative care. The SVD/PVD ratio (\u0026ge;\u0026thinsp;0.7) proved to be a strong predictor of PVT, offering a useful parameter for risk assessment. It is expected that preoperative evaluation of PVT risk and intraoperative fluid management strategies based on these findings may help prevent PVT development, improving patient outcomes after LS.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank Enago (https://www.enago.jp/) for editing a draft of this manuscript. We are grateful to Eiji Sadashima (Department of Medical Research Institute, Saga-Ken Medical Center Koseikan, Saga, Japan) for his contribution to the statistical analyses.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare no conflicts of interest in association with the present study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval:\u0026nbsp;\u003c/strong\u003eThis study was performed in accordance with the Ethical Guidelines for Clinical Research published by the Ministry of Health, Labour and Welfare of Japan on July 30, 2003 (revised in 2008) and complied with the Declaration of Helsinki (revised in 2008). The Ethics Committee for Clinical Research of Kyushu University Hospital approved this study (No. 24278).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions:\u0026nbsp;\u003c/strong\u003eAtsuhisa Fukuta: designed research/study, performed research/study, analyzed data, and wrote the paper. Toshiharu Matsuura: collected data and revised the manuscript. Yasuyuki Uchida: collected data. Naonori Kawakubo: collected data. Takuya Kondo: collected data. Yoshiaki Takahashi: collected data. Koichiro Yoshimaru: collected data. Kouji Nagata: collected data, Tatsuro Tajiri: revised the manuscript. All authors reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent was obtained from all patients\u0026rsquo; guardians.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo datasets were generated or analyzed during the current study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDelaitre B, Maignien B (1992) Laparoscopic splenectomy technical aspects. 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World J Gastrointest Endosc 9:428\u0026ndash;437. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.4253/wjge.v9.i9.428\u003c/span\u003e\u003cspan address=\"10.4253/wjge.v9.i9.428\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ede\u0026rsquo;Angelis N, Abdalla S, Lizzi V et al (2017) Incidence and predictors of portal and splenic vein thrombosis after pure laparoscopic splenectomy. Surgery 162:1219\u0026ndash;1230. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.surg.2017.07.016\u003c/span\u003e\u003cspan address=\"10.1016/j.surg.2017.07.016\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\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":"pediatric-surgery-international","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pesi","sideBox":"Learn more about [Pediatric Surgery International](http://link.springer.com/journal/383)","snPcode":"383","submissionUrl":"https://submission.nature.com/new-submission/383/3","title":"Pediatric Surgery International","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Portal vein thrombosis, Laparoscopic splenectomy, Splenic vein, Risk factor, SVD/PVD ratio","lastPublishedDoi":"10.21203/rs.3.rs-7291537/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7291537/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e\u003cp\u003eThis study aimed to identify predictors of portal vein thrombosis (PVT) after laparoscopic splenectomy (LS) in children.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003ePatients who underwent LS between September 2014 and August 2024 were retrospectively reviewed. Preoperative and intraoperative clinical data were compared between those with and without PVT. The splenic vein diameter (SVD) was measured at 2, 4, and 6 cm from the portal vein (PV) junction using preoperative transaxial computed tomography images.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eAmong 21 patients who underwent LS, those with PVT were significantly older, more likely to be female, and had a higher body mass index. Although splenic maximum diameter, PV diameter, and the spleen volume/standard spleen volume ratio showed no significant differences, SVD was significantly larger at all measured locations in patients with PVT. Additionally, the SVD/portal vein diameter (PVD) ratio was significantly higher at all measured locations in these patients. Receiver operating characteristic analysis identified the SVD/PVD ratio as the most reliable predictor of PVT development, with an optimal cutoff value of 0.7.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eAn SVD/PVD ratio\u0026thinsp;\u0026ge;\u0026thinsp;0.7 is a strong predictor of PVT after LS in children. Measuring this ratio preoperatively may identify high-risk patients, allowing for closer monitoring and potential preventive interventions to reduce PVT incidence.\u003c/p\u003e","manuscriptTitle":"Splenic vein diameter/portal vein diameter ratio as a predictor of portal vein thrombosis after laparoscopic splenectomy in children","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-27 06:20:35","doi":"10.21203/rs.3.rs-7291537/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Accepted","date":"2025-08-17T09:03:09+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-17T09:02:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"340165079514415562491512844803786995236","date":"2025-08-17T09:01:52+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-17T08:59:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-09T14:10:59+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-08T13:03:01+00:00","index":"","fulltext":""},{"type":"submitted","content":"Pediatric Surgery International","date":"2025-08-04T13:00:49+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"pediatric-surgery-international","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pesi","sideBox":"Learn more about [Pediatric Surgery International](http://link.springer.com/journal/383)","snPcode":"383","submissionUrl":"https://submission.nature.com/new-submission/383/3","title":"Pediatric Surgery International","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"a5158906-07ec-448b-b802-7234dd2aa769","owner":[],"postedDate":"August 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-09-01T16:07:23+00:00","versionOfRecord":{"articleIdentity":"rs-7291537","link":"https://doi.org/10.1007/s00383-025-06171-y","journal":{"identity":"pediatric-surgery-international","isVorOnly":false,"title":"Pediatric Surgery International"},"publishedOn":"2025-08-29 15:57:53","publishedOnDateReadable":"August 29th, 2025"},"versionCreatedAt":"2025-08-27 06:20:35","video":"","vorDoi":"10.1007/s00383-025-06171-y","vorDoiUrl":"https://doi.org/10.1007/s00383-025-06171-y","workflowStages":[]},"version":"v1","identity":"rs-7291537","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7291537","identity":"rs-7291537","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}