Bladder neck angle as an anatomical predictor of conservative treatment failure and the need for surgery in benign prostatic hyperplasia

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Methods Outpatients presenting with bothersome LUTS or acute urinary retention (AUR) due to benign prostatic hyperplasia were included in the cohort. The prostate volume, intravesical prostatic protrusion, BNA, and postvoid residual volume were recorded. In patients with AUR, TWOC was performed after 2 weeks of alpha-blocker therapy; those with LUTS received alpha-blockers and 5-alpha reductase inhibitors for 12 months. Surgery was recommended for patients who experienced failure of conservative treatment. The uroflowmetry and International Prostate Symptom Score (IPSS) changes were assessed from baseline to 12 months after treatment. Results In the efficacy analysis, 66 patients with AUR were recruited, and 32 patients (48.5%) experienced unsuccessful TWOC. The AUC for BNA to predict unsuccessful TWOC was 0.855 (95% CI 0.76–0.94), and for intravesical prostatic protrusion, the AUC was 0.794 (95% CI 0.68–0.91). In 335 patients with LUTS, from baseline to month 3, the change in IPSS after combination therapy was − 2.17 and − 4.89 in patients with large and small BNAs, respectively. Conclusions BNA is a promising anatomical predictor of TWOC outcome in AUR and may help identify LUTS patients who are likely to experience greater benefit from combination therapy. Incorporating BNA into clinical assessment may improve risk stratification and treatment planning in BPH management. Prostate Bladder Neck Angle Lower Urinary Trac Symptoms Acute Urinary Retention Ultrasonography Figures Figure 1 Figure 2 Introduction Lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) are prevalent in older men; nearly 60% of men over 60 years old have been affected, and the prevalence increases with age 1 . The treatment of BPH includes watchful waiting, pharmacological therapy, and surgery. Transurethral resection of the prostate (TURP) is the gold standard in the surgical management of BPH and can significantly improve the peak flow rate (Qmax) and International Prostate Symptom Score (IPSS) 2 . However, complications from TURP, such as hematuria, incontinence, and bladder neck stenosis, cannot be ignored 3 . Thus, pharmacological therapy is widely accepted as the initial treatment for LUTS, and both monotherapy and combination therapy with alpha-adrenergic antagonist (α-blocker) and 5-alpha reductase inhibitor (5-ARI) have been confirmed to be effective 4 – 6 . Rather than being a purely localized urological disorder, BPH represents one aspect of the broader aging phenotype of the male genitourinary system, in which chronic low-grade inflammation, hormonal changes, and tissue remodeling converge to produce progressive bladder outlet obstruction. Clinically, this process manifests as impaired urinary flow, increased postvoid residual urine, acute urinary retention (AUR). The treatment of AUR involves catheterizing patients to void and relieve the pain and then offering trial without catheter (TWOC) and oral α-blocker before TWOC, which has been reported to improve the outcome of TWOC 7 – 9 . Nevertheless, not all patients benefit from conservative treatment; approximately 25% of patients with LUTS opt for surgery due to pharmacological therapy failure, and only 23–55% of patients with AUR may successfully micturate after TWOC 10 . Thus, identifying those who may not experience symptom improvement following conservative treatment is essential. Previous studies have shown that prostate volume (PV) may not be strongly associated with LUTS and AUR 11 . In contrast, intravesical prostatic protrusion (IPP) has been reported to be a useful factor in predicting the outcome of TWOC and is significantly associated with LUTS 12 – 14 . Our previous study proved that IPP is not the only factor affecting the structure of the bladder neck; the bladder neck angle (BNA), the angulation at the anterior and posterior walls of the bladder neck, also contributes to the funnel effect in the bladder neck 15 . However, real-world evidence linking BNA to clinical outcomes—both short-term functional recovery and longer-term response to combination therapy—remains scarce. In this prospective study of men with BPH presenting with AUR or LUTS, we tested whether a larger BNA, as an anatomical aging phenotype of the bladder outlet, predicts TWOC failure and attenuated symptomatic improvement with combination therapy. Materials and Methods The local institutional review board approved this prospective study. From September 2023 to May 2024, first-visit patients with bothersome LUTS or AUR due to BPH were recruited. The exclusion criteria included renal failure, type 2 diabetes, prostate cancer, previous unsuccessful TWOC, any urethral disease that can affect micturition, history of urethral surgery, α-blocker or 5-ARI therapy; patients with recurrent urinary retention, severe urinary tract infection, use of drugs predisposing to urine retention (anticholinergic, beta-adrenergic, diuretics), history of pelvic surgery, and bladder calculi requiring immediate surgical therapy were also excluded. After catheterization, patients with AUR took 0.2 mg tamsulosin hydrochloride sustained release capsules (α-blocker) daily, and TWOC was performed after two weeks. Patients with unsuccessful TWOC, if the patients were unable to void and had a residual volume > 200 ml, were advised to undergo TURP. Patients with bothersome LUTS but without AUR received the combination therapy, 0.2 mg tamsulosin and 5 mg finasteride tablets (5-ARI) taken orally each day for a period of one year. Patients with clinical progression (increase in IPSS ≥ 4 above baseline, AUR, or urinary tract infection) or incomplete response to therapy were advised to undergo TURP. All patients underwent transrectal ultrasound (TRUS) before treatment, which was performed by the same urologist using a 5–10 MHz endorectal biplanar probe. The PV was calculated using the ellipse formula (length × width × height × π/6). The IPP was measured as the distance from the base of the bladder to the top of the prostate that protruded into the bladder 12 . The BNA was the angle between the anterior and posterior walls at the bladder neck 15 (Fig. 1 A, B). The PVR was measured by transabdominal ultrasound scan. The uroflowmetric measurements were performed in patients without AUR (in patients with AUR, there was no clinical significance to perform urodynamic evaluation), and the IPSS was evaluated in all patients. The follow-up visits were conducted three, six and twelve months after medical treatment or surgery, and the review included IPSS, adverse complications, and prostate ultrasound examination. Continuous variables were expressed as median (interquartile range, IQR) and compared between two independent groups using the Mann-Whitney U test. Categorical variables were compared using the chi-square test or Fisher’s exact test when appropriate. A two-tailed P value < 0.05 was considered statistically significant. Statistical analyses were performed using R (version 4.0.2). Results A total of 523 patients were recruited, and 401 (76%) finished the 12-month visit. According to the presence of AUR, the patients were subdivided into two groups: 66 patients had AUR, among whom 34 (51.5%) had successful TWOC; and 32 (48.5%) patients experienced failed TWOC, all of whom elected surgical options such as TURP. Among those patients who received combination therapy (n = 335), 23 (6.8%) elected to undergo TURP due to pharmacological therapy failure; the patients’ characteristics are summarized in Table 1 . Table 1 Baseline demographics and patient characteristics AUR NO AUR TWOC successful TWOC unsuccessful Combination therapy effective Combination therapy ineffective Patients (n) 34 32 312 23 Age (years) 64.15 (57.21–75.08) 68.93 (62.75–74.91) 58.01 (51.93–67.52) 68.09 (65.39–73.54) IPSS 22.45 (20.07–25.43) 25.46 (22.19–26.62) 13.69 (9.03–18.38) 22.61 (20.05–24.42) QOL 5.00 (5.00–6.00) 6.00 (5.00–6.00) 5.00 (5.00–6.00) 6.00 (5.00–6.00) Qmax (mL/sec) - - 13.85 (11.50-17.83) 9.02 (8.22–10.34) PVR (mL) 123.15 (104.03-146.27) 167.12 (153.53-259.56) 11.34 (3.02–21.10) 43.70 (18.50-54.55) PV (mL) 34.47 (25.42–56.75) 62.98 (44.38–82.45) 30.34 (24.40-38.68) 60.83 (42.51–80.91) IPP (mm) 8.02 (3.12–9.81) 15.52 (11.34–18.11) 1.81 (0.00-9.93) 14.66 (11.72–16.37) BNA (°) 77.94 (71.92–87.40) 93.09 (89.29–99.72) 63.28 (55.83–73.25) 91.46 (83.28–96.51) Data are presented as median (interquartile range). According to linear regression analysis, BNA was strongly correlated with IPP (R = 0.55, P < 0.001). However, the correlation between IPP and BNA was significantly higher in the AUR group than in the combination therapy group (R = 0.58, P < 0.001 vs. R = 0.37, P < 0.001) (Fig. 2 A, B); additionally, BNA was not correlated with IPP when IPP < 10 mm (R = 0.14, P = 0.17). Patients with successful TWOC had a smaller PV (34.47 mL, IQR 25.42–56.75 vs. 62.98mL, IQR 44.38–82.45, P = 0.007), IPP (8.02 mm, IQR 3.12–9.81 vs. 15.52 mm, IQR 11.34–18.11, P < 0.001) and BNA (77.94°, IQR 71.92–87.40 vs. 93.09°, IQR 89.29–99.72, P < 0.001) than those with unsuccessful TWOC. ROC curve analysis revealed that BNA was more accurate than IPP and PV in predicting successful TWOC in the AUR group (AUC = 0.85, 0.80 and 0.74, respectively) (Fig. 2 C), the best cutoff for BNA was 89.94° (sensitivity = 0.75, specificity = 0.84), and the optimal cutoff value for IPP was 10.25 mm (sensitivity = 0.85, specificity = 0.75). Furthermore, the combination of the three factors could significantly enhance the accuracy in predicting successful TWOC. In the combination therapy group, the prognostic value of BNA in predicting combination therapy failure was high (AUC = 0.87), and the best cutoff value was 75.85° (sensitivity = 0.78, specificity = 0.87). In patients who underwent TURP, prostatic symptoms secondary to BPH were significantly improved after surgery and sustained through 1 year, and there was no difference based on whether or not the BNA was larger than 89.94°. From baseline to month 12, the mean IPSS decreased to 6.64 and 6.36 (P = 0.15) (Fig. 2 D). However, in the combination therapy group, when the BNA was larger than 75.85°, the improvement in IPSS was significantly weaker than that in those with a small BNA (decrease 2.17 vs. 4.89 at month 3 compared to baseline, P < 0.001) (Fig. 2 E). Discussion Many prostates anatomic characteristics have been proven to be correlated with the severity of LUTS, such as the PV, translation zone volume, and prostatic urethral angulation 16 – 18 . However, the pathogenic mechanism of LUTS is complicated; in addition to prostatic enlargement, functional or structural abnormalities of the bladder neck may also contribute to LUTS 19 . As reported by Chia et al., when the enlargement of the prostatic median lobe causes protrusion from the base of the bladder, the protruded portion of the prostate will form a “ball-valve” type of structure, resulting in obstruction of the bladder neck 14 . Thus, patients with a large IPP may be more likely to have bladder outlet obstruction due to protrusion of the prostate, which changes the form of the bladder neck 20 . On the other hand, previous studies have shown that the IPP is a strong predictor of TWOC outcome, especially when it exceeds 10 mm, and nearly 70%-87% of patients have an unsuccessful TWOC 12 , 21 . Our results have proven that when the IPP is larger than 10.25 mm (the best IPP cutoff to predict TWOC failure), 78% of AUR patients have an unsuccessful TWOC; these results are similar to the findings above. Additionally, our previous study found that the BNA could also reflect morphological changes of the bladder neck; the larger the BNA is, the more severe the disruption of the bladder neck 15 . Many factors can affect the BNA through damage to the structure of the bladder neck, such as the volume of urinary retention, abnormal tension of the bladder neck smooth muscles, and enlargement of the prostatic anterior or lateral lobe. However, when the prostatic middle lobe protrudes from the bladder base, enlargement of the prostate squeezes the funnel structure of the bladder neck, causing elevation of the internal urethral orifice and flipping of the bladder neck wall outward, especially in AUR patients, the BNA was significantly correlated with IPP. There is still no consensus on the pathogenesis of AUR. Previous studies have established that large PV and IPP increase the risk of AUR and even cause TWOC failure 21 , 22 . We agree with the conclusion above. Our results showed that in patients with unsuccessful TWOC, the PV, IPP, and BNA were significantly larger than those in patients with successful TWOC. Moreover, ROC curve analysis showed that the BNA was more accurate than PV and IPP in predicting unsuccessful TWOC at the optimal cutoff of 89.94° (sensitivity = 0.75, specificity = 0.84). In the present study, α-blocker was orally administered before TWOC in the patients with AUR, as recommended in the AUA guidelines. However, the efficacy of α-blocker to improve the outcome of TWOC is still controversial. As reported by Shah et al., oral α-blocker did not improve the outcome of TWOC or reduce the risk of recurrent urinary retention. A potential explanation for this discrepancy is that patients with large BNAs and IPPs may be nonresponsive to therapy with α-blocker or TWOC; when the mean IPP or BNA in the cohort is large, the α-blocker effect is limited, resulting in a decreased success rate of TWOC. In our study, the failure rate of TWOC was 48% in the AUR group; however, in the group with IPPs larger than 10.24 mm or BNAs larger than 89.94°, the unsuccessful rates of TWOC were 78% and 83%, respectively. With the progression of BPH, the muscle bundles of the bladder neck will gradually be replaced by collagenous tissue 23 . Unlike the dynamic obstruction caused by the unusual tone of smooth muscle, which can be relaxed with receptor antagonists, the fibrotic bladder neck is less likely to respond to α-blockers, and the large BNA, caused by the lower elasticity of the degenerative bladder neck, is unlikely to change after TWOC. Thus, the reduction of the funneling effect due to disruption of the funnel-shaped bladder neck will not improve. Without the catheter, more pressure is still required to open the internal urethral orifice to begin voiding, and according to the Reynolds Eq. 2 4 , the high initial urine flow speed, due to the higher pressure, will cause irregular turbulence and dyskinetic movement during urination. Hence, this subset will benefit from surgical intervention. Traditionally, the first-line treatment for LUTS is medical therapy, combination therapy significantly improves the IPSS, compared to a placebo, at month 3 6 . In the present study, the correlation between BNA and IPP in the combination therapy group was weaker than that in the AUR group (R = 0.372 vs. 0.581, P < 0.001), and the ROC analysis showed that the best cutoff for BNA to predict the failure of medical therapy was 75.85° (sensitivity was 0.78 and specificity was 0.87). When the patient’s BNA was larger than 75.85°, the improvement in IPSS was less than that in those with a small BNA. In addition, in the large BNA group, the late improvement in IPSS at months 9 and 12 may result from patients undergoing surgery dropping out of the statistics, this did not mean the improvements were deferred. By inhibiting the conversion of testosterone to dihydrotestosterone in prostatic stromal cells, 5-ARI reduces the stimulating effect of androgen on glandular epithelial cells, causing a decrease in PV 25 ; however, the lower dihydrotestosterone may not reverse the fibrosis of the degenerate bladder neck, and due to the absence of stromal cells, the protrusion of the prostatic middle lobe may be insensitive to dihydrotestosterone 26 ; thus, the effect of combination therapy was poor in patients with large BNA. After the patient was converted to a surgical intervention, the improvement in IPSS was significant regardless of BNA; the resection of the prostate formed an artificial funnel-shaped structure that increase the funnel effect and removed the obstruction (Fig. 1 C). Such improvement in urination may not be achieved with medical therapy. However, there were 3 patients, both with small PVs and large BNAs (the mean PV and BNA were 26.97 ml and 92.71°), who needed to be retreated due to bladder neck stenosis, which may be related to overresection of the degenerated bladder neck. A prophylactic bladder neck incision could be considered to reduce the incidence 27 , but more data is still needed to conduct a meaningful analysis. There are some limitations that need to be mentioned. Although both the BNA and IPP can be easily measured on the same sagittal ultrasonographic image, in the present study, the measurement of anatomical factors was performed by TRUS, which is invasive; thus, further study should compare the accuracy of measurements obtained with transabdominal ultrasound and TRUS. On the other hand, the measurement was performed in the resting state, but the form of the bladder neck may change during micturition. Conclusion In aging men with BPH/LUTS, a larger bladder neck angle emerges as an anatomical aging marker associated with both TWOC failure after AUR and a poorer symptomatic response to combination therapy. Incorporating BNA into the evaluation of older patients may improve risk stratification and support earlier, individualized intervention to prevent functional decline. Declarations Ethics approval and consent to participate: This study was conducted in accordance with the ethical principles of the Declaration of Helsinki, and approved by the Ethics Committee of Jinan University. Both patients and controls provided written informed consent. Consent for publication: Not applicable Availability of data and materials: The datasets generated and used in this study are available from the corresponding author on reasonable request. Competing interests: The authors declare that they have no competing interests. Funding ： None. Author contribution ： All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by YL, RZ, YYL, YHW, LSZ, YMZ. Project administration, review of the manuscript was performed by JH. RZ reviewed the pathological result of biopsies. In the perspective of urology, YMZ made the supervision, project administration, review of the manuscript. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Acknowledgements: Not applicable. References Devlin CM, Simms MS, Maitland NJ. Benign prostatic hyperplasia - what do we know? BJU Int. 2021; 127:389-399. Lerner LB, McVary KT, Barry MJ, et al. Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA GUIDELINE PART II-Surgical Evaluation and Treatment. J Urol. 2021; 206:818-826. Rassweiler J, Teber D, Kuntz R, et al. 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World J Urol. 2020; 38:1997-2003. Abrams P, Chapple C, Khoury S, et al. Evaluation and treatment of lower urinary tract symptoms in older men. J Urol. 2009; 181:1779-87. Franco G, De Nunzio C, Leonardo C, et al. Ultrasound assessment of intravesical prostatic protrusion and detrusor wall thickness--new standards for noninvasive bladder outlet obstruction diagnosis? J Urol. 2010; 183:2270-4. Mariappan P, Brown DJ, McNeill AS. Intravesical prostatic protrusion is better than prostate volume in predicting the outcome of trial without catheter in white men presenting with acute urinary retention: a prospective clinical study. J Urol. 2007; 178:573-7. Yoon PD, Chalasani V, Woo HH. Systematic review and meta-analysis on management of acute urinary retention. Prostate Cancer Prostatic Dis. 2015; 18:297-302. Hinata N, Miyake H, Murakami G, Abe S, Fujisawa M. Bladder Neck Muscle Degeneration in Patients with Prostatic Hyperplasia. J Urol. 2016; 195:206-12. Martinez-Borges AR. Turbulent urinary flow in the urethra could be a causal factor for benign prostatic hyperplasia. Med Hypotheses. 2006; 67:871-5. McConnell JD, Bruskewitz R, Walsh P, et al. The effect of finasteride on the risk of acute urinary retention and the need for surgical treatment among men with benign prostatic hyperplasia. Finasteride Long-Term Efficacy and Safety Study Group. N Engl J Med. 1998; 338:557-63. Hirayama K, Masui K, Hamada A, et al. Evaluation of Intravesical Prostatic Protrusion as a Predictor of Dutasteride-Resistant Lower Urinary Tract Symptoms/Benign Prostatic Enlargement With a High Likelihood of Surgical Intervention. Urology. 2015; 86:565-9. Rassweiler J, Teber D, Kuntz R, et al. Complications of transurethral resection of the prostate (TURP)--incidence, management, and prevention. Eur Urol. 2006; 50:969-79. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 21 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviewers agreed at journal 11 Apr, 2026 Reviewers agreed at journal 12 Feb, 2026 Reviews received at journal 11 Feb, 2026 Reviewers agreed at journal 10 Feb, 2026 Reviewers invited by journal 08 Feb, 2026 Editor assigned by journal 29 Jan, 2026 Submission checks completed at journal 29 Jan, 2026 First submitted to journal 26 Jan, 2026 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-8703855","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":590251909,"identity":"792fc737-7131-440a-b9cf-7e7a07347c16","order_by":0,"name":"Yi Li","email":"","orcid":"","institution":"The Affiliated Guangdong Second Provincial General Hospital of Jinan University","correspondingAuthor":false,"prefix":"","firstName":"Yi","middleName":"","lastName":"Li","suffix":""},{"id":590251910,"identity":"309f4ecf-cba5-400d-a9c0-6ec9bd20347e","order_by":1,"name":"Rui Zeng","email":"","orcid":"","institution":"South China University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Rui","middleName":"","lastName":"Zeng","suffix":""},{"id":590251911,"identity":"563bc39b-13a8-4ce3-b43c-1663bbbbb317","order_by":2,"name":"Yin-Ying Liang","email":"","orcid":"","institution":"The First Affiliated Hospital of Jinan University","correspondingAuthor":false,"prefix":"","firstName":"Yin-Ying","middleName":"","lastName":"Liang","suffix":""},{"id":590251912,"identity":"5e727ce1-340c-480e-8b4f-1cdb463ae637","order_by":3,"name":"Yu-Hang Wang","email":"","orcid":"","institution":"The First Affiliated Hospital of Jinan University","correspondingAuthor":false,"prefix":"","firstName":"Yu-Hang","middleName":"","lastName":"Wang","suffix":""},{"id":590251913,"identity":"d17362ad-bfe2-4565-9a92-d75ad594ecf8","order_by":4,"name":"Li-Su Zhang","email":"","orcid":"","institution":"The First Affiliated Hospital of Jinan University","correspondingAuthor":false,"prefix":"","firstName":"Li-Su","middleName":"","lastName":"Zhang","suffix":""},{"id":590251914,"identity":"e8b6616e-bf67-4615-ae14-e7823dcc5496","order_by":5,"name":"Yu-Min Zhuo","email":"","orcid":"","institution":"The First Affiliated Hospital of Jinan University","correspondingAuthor":false,"prefix":"","firstName":"Yu-Min","middleName":"","lastName":"Zhuo","suffix":""},{"id":590251915,"identity":"4082c864-fc3d-43cd-b27e-8b7a6464ce4a","order_by":6,"name":"Jun Huang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAz0lEQVRIiWNgGAWjYDACCTDJJsfYAKaJ0MED1WJMshaGxAYGYrXYS/cYfi74xZfePLvHgOFD2WEG/tkNBGyROWMsPbOPLbdxzhkDxhnnDjNI3DlAyGE5BtK8PUAtM3IMmHnbDjMYSCQQ1GL8G6glnRGk5S+RWsykeX6wJYC1MBKl5UZamTVvA5th44y0goM959J5JG4Q0MI+I3nzbZ4/x+QNZyRvfPCjzFqOfwYBLWDA2HaMwbCBgeEAyFoi1IPAnxoGeSKVjoJRMApGwQgEALMAPY032KE3AAAAAElFTkSuQmCC","orcid":"","institution":"The First Affiliated Hospital of Jinan University","correspondingAuthor":true,"prefix":"","firstName":"Jun","middleName":"","lastName":"Huang","suffix":""}],"badges":[],"createdAt":"2026-01-26 21:23:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8703855/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8703855/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102593809,"identity":"d03edd01-eca4-47bd-9703-45309bd2d7f7","added_by":"auto","created_at":"2026-02-13 11:51:57","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":18833456,"visible":true,"origin":"","legend":"\u003cp\u003eSagittaltransrectal prostatic ultrasonography. A, the measurement of BNA, where θ° indicates the BNA; B, the measurement of IPP; C, one year after TURP; D-F, cartoon drawing of the same.\u003c/p\u003e","description":"","filename":"fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-8703855/v1/2274843a28cec5b5da0737fe.png"},{"id":102593807,"identity":"3d7776c8-a6a6-4cad-917c-7e038f46ea8b","added_by":"auto","created_at":"2026-02-13 11:51:57","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":685506,"visible":true,"origin":"","legend":"\u003cp\u003eLinear regression analysis between IPP and BNA; A, AUR group (R=0.581, P\u0026lt;0.001); B, combination therapy group (R=0.372, P\u0026lt;0.001). C, ROC curve analysis showing the accuracy of PV, IPP, and BNA in predicting unsuccessful TWOC; D, the mean changes in IPSS (95% CI) between the BNA larger and smaller than 89.94° groups in patients who underwent surgical therapy during the study period; E, The adjusted mean change in IPSS (95% CI) between the BNA larger and smaller than 75.85° groups in patients with combination therapy from baseline to month 12.\u003c/p\u003e\n\u003cp\u003e* Indicates P\u0026lt;0.001 for the comparison between the two groups\u003c/p\u003e","description":"","filename":"fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-8703855/v1/1ddbe05f88bc4765d52e98e0.png"},{"id":107868491,"identity":"58b28d65-fdc5-4473-ab3e-dd3f3fa66379","added_by":"auto","created_at":"2026-04-27 07:19:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":18155874,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8703855/v1/c7e07519-09aa-4c04-a245-a472dc876f63.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Bladder neck angle as an anatomical predictor of conservative treatment failure and the need for surgery in benign prostatic hyperplasia","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) are prevalent in older men; nearly 60% of men over 60 years old have been affected, and the prevalence increases with age\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. The treatment of BPH includes watchful waiting, pharmacological therapy, and surgery. Transurethral resection of the prostate (TURP) is the gold standard in the surgical management of BPH and can significantly improve the peak flow rate (Qmax) and International Prostate Symptom Score (IPSS)\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. However, complications from TURP, such as hematuria, incontinence, and bladder neck stenosis, cannot be ignored\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. Thus, pharmacological therapy is widely accepted as the initial treatment for LUTS, and both monotherapy and combination therapy with alpha-adrenergic antagonist (α-blocker) and 5-alpha reductase inhibitor (5-ARI) have been confirmed to be effective\u003csup\u003e\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eRather than being a purely localized urological disorder, BPH represents one aspect of the broader aging phenotype of the male genitourinary system, in which chronic low-grade inflammation, hormonal changes, and tissue remodeling converge to produce progressive bladder outlet obstruction. Clinically, this process manifests as impaired urinary flow, increased postvoid residual urine, acute urinary retention (AUR). The treatment of AUR involves catheterizing patients to void and relieve the pain and then offering trial without catheter (TWOC) and oral α-blocker before TWOC, which has been reported to improve the outcome of TWOC\u003csup\u003e\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eNevertheless, not all patients benefit from conservative treatment; approximately 25% of patients with LUTS opt for surgery due to pharmacological therapy failure, and only 23\u0026ndash;55% of patients with AUR may successfully micturate after TWOC\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. Thus, identifying those who may not experience symptom improvement following conservative treatment is essential. Previous studies have shown that prostate volume (PV) may not be strongly associated with LUTS and AUR\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. In contrast, intravesical prostatic protrusion (IPP) has been reported to be a useful factor in predicting the outcome of TWOC and is significantly associated with LUTS\u003csup\u003e\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eOur previous study proved that IPP is not the only factor affecting the structure of the bladder neck; the bladder neck angle (BNA), the angulation at the anterior and posterior walls of the bladder neck, also contributes to the funnel effect in the bladder neck\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e. However, real-world evidence linking BNA to clinical outcomes\u0026mdash;both short-term functional recovery and longer-term response to combination therapy\u0026mdash;remains scarce. In this prospective study of men with BPH presenting with AUR or LUTS, we tested whether a larger BNA, as an anatomical aging phenotype of the bladder outlet, predicts TWOC failure and attenuated symptomatic improvement with combination therapy.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e The local institutional review board approved this prospective study. From September 2023 to May 2024, first-visit patients with bothersome LUTS or AUR due to BPH were recruited. The exclusion criteria included renal failure, type 2 diabetes, prostate cancer, previous unsuccessful TWOC, any urethral disease that can affect micturition, history of urethral surgery, α-blocker or 5-ARI therapy; patients with recurrent urinary retention, severe urinary tract infection, use of drugs predisposing to urine retention (anticholinergic, beta-adrenergic, diuretics), history of pelvic surgery, and bladder calculi requiring immediate surgical therapy were also excluded.\u003c/p\u003e \u003cp\u003eAfter catheterization, patients with AUR took 0.2 mg tamsulosin hydrochloride sustained release capsules (α-blocker) daily, and TWOC was performed after two weeks. Patients with unsuccessful TWOC, if the patients were unable to void and had a residual volume\u0026thinsp;\u0026gt;\u0026thinsp;200 ml, were advised to undergo TURP. Patients with bothersome LUTS but without AUR received the combination therapy, 0.2 mg tamsulosin and 5 mg finasteride tablets (5-ARI) taken orally each day for a period of one year. Patients with clinical progression (increase in IPSS\u0026thinsp;\u0026ge;\u0026thinsp;4 above baseline, AUR, or urinary tract infection) or incomplete response to therapy were advised to undergo TURP.\u003c/p\u003e \u003cp\u003eAll patients underwent transrectal ultrasound (TRUS) before treatment, which was performed by the same urologist using a 5\u0026ndash;10 MHz endorectal biplanar probe. The PV was calculated using the ellipse formula (length \u0026times; width \u0026times; height\u0026thinsp;\u0026times;\u0026thinsp;π/6). The IPP was measured as the distance from the base of the bladder to the top of the prostate that protruded into the bladder\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. The BNA was the angle between the anterior and posterior walls at the bladder neck\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA, B). The PVR was measured by transabdominal ultrasound scan. The uroflowmetric measurements were performed in patients without AUR (in patients with AUR, there was no clinical significance to perform urodynamic evaluation), and the IPSS was evaluated in all patients. The follow-up visits were conducted three, six and twelve months after medical treatment or surgery, and the review included IPSS, adverse complications, and prostate ultrasound examination.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eContinuous variables were expressed as median (interquartile range, IQR) and compared between two independent groups using the Mann-Whitney U test. Categorical variables were compared using the chi-square test or Fisher\u0026rsquo;s exact test when appropriate. A two-tailed P value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant. Statistical analyses were performed using R (version 4.0.2).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 523 patients were recruited, and 401 (76%) finished the 12-month visit. According to the presence of AUR, the patients were subdivided into two groups: 66 patients had AUR, among whom 34 (51.5%) had successful TWOC; and 32 (48.5%) patients experienced failed TWOC, all of whom elected surgical options such as TURP. Among those patients who received combination therapy (n\u0026thinsp;=\u0026thinsp;335), 23 (6.8%) elected to undergo TURP due to pharmacological therapy failure; the patients\u0026rsquo; characteristics are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\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\u003eBaseline demographics and patient characteristics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" 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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eAUR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eNO AUR\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTWOC\u003c/p\u003e \u003cp\u003esuccessful\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTWOC\u003c/p\u003e \u003cp\u003eunsuccessful\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCombination therapy effective\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCombination\u003c/p\u003e \u003cp\u003etherapy ineffective\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePatients (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e312\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e64.15 (57.21\u0026ndash;75.08)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68.93 (62.75\u0026ndash;74.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e58.01 (51.93\u0026ndash;67.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e68.09 (65.39\u0026ndash;73.54)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIPSS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.45 (20.07\u0026ndash;25.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.46 (22.19\u0026ndash;26.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.69 (9.03\u0026ndash;18.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e22.61 (20.05\u0026ndash;24.42)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQOL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.00 (5.00\u0026ndash;6.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.00 (5.00\u0026ndash;6.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.00 (5.00\u0026ndash;6.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6.00 (5.00\u0026ndash;6.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQmax (mL/sec)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.85 (11.50-17.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.02 (8.22\u0026ndash;10.34)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePVR (mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e123.15 (104.03-146.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e167.12 (153.53-259.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e11.34 (3.02\u0026ndash;21.10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e43.70 (18.50-54.55)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePV (mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34.47 (25.42\u0026ndash;56.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62.98 (44.38\u0026ndash;82.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e30.34 (24.40-38.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e60.83 (42.51\u0026ndash;80.91)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIPP (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.02 (3.12\u0026ndash;9.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15.52 (11.34\u0026ndash;18.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.81 (0.00-9.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e14.66 (11.72\u0026ndash;16.37)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBNA (\u0026deg;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e77.94 (71.92\u0026ndash;87.40)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e93.09 (89.29\u0026ndash;99.72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e63.28 (55.83\u0026ndash;73.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e91.46 (83.28\u0026ndash;96.51)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eData are presented as median (interquartile range).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAccording to linear regression analysis, BNA was strongly correlated with IPP (R\u0026thinsp;=\u0026thinsp;0.55, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, the correlation between IPP and BNA was significantly higher in the AUR group than in the combination therapy group (R\u0026thinsp;=\u0026thinsp;0.58, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001 vs. R\u0026thinsp;=\u0026thinsp;0.37, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA, B); additionally, BNA was not correlated with IPP when IPP\u0026thinsp;\u0026lt;\u0026thinsp;10 mm (R\u0026thinsp;=\u0026thinsp;0.14, P\u0026thinsp;=\u0026thinsp;0.17).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePatients with successful TWOC had a smaller PV (34.47 mL, IQR 25.42\u0026ndash;56.75 vs. 62.98mL, IQR 44.38\u0026ndash;82.45, P\u0026thinsp;=\u0026thinsp;0.007), IPP (8.02 mm, IQR 3.12\u0026ndash;9.81 vs. 15.52 mm, IQR 11.34\u0026ndash;18.11, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and BNA (77.94\u0026deg;, IQR 71.92\u0026ndash;87.40 vs. 93.09\u0026deg;, IQR 89.29\u0026ndash;99.72, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) than those with unsuccessful TWOC. ROC curve analysis revealed that BNA was more accurate than IPP and PV in predicting successful TWOC in the AUR group (AUC\u0026thinsp;=\u0026thinsp;0.85, 0.80 and 0.74, respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC), the best cutoff for BNA was 89.94\u0026deg; (sensitivity\u0026thinsp;=\u0026thinsp;0.75, specificity\u0026thinsp;=\u0026thinsp;0.84), and the optimal cutoff value for IPP was 10.25 mm (sensitivity\u0026thinsp;=\u0026thinsp;0.85, specificity\u0026thinsp;=\u0026thinsp;0.75). Furthermore, the combination of the three factors could significantly enhance the accuracy in predicting successful TWOC. In the combination therapy group, the prognostic value of BNA in predicting combination therapy failure was high (AUC\u0026thinsp;=\u0026thinsp;0.87), and the best cutoff value was 75.85\u0026deg; (sensitivity\u0026thinsp;=\u0026thinsp;0.78, specificity\u0026thinsp;=\u0026thinsp;0.87).\u003c/p\u003e \u003cp\u003eIn patients who underwent TURP, prostatic symptoms secondary to BPH were significantly improved after surgery and sustained through 1 year, and there was no difference based on whether or not the BNA was larger than 89.94\u0026deg;. From baseline to month 12, the mean IPSS decreased to 6.64 and 6.36 (P\u0026thinsp;=\u0026thinsp;0.15) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eD). However, in the combination therapy group, when the BNA was larger than 75.85\u0026deg;, the improvement in IPSS was significantly weaker than that in those with a small BNA (decrease 2.17 vs. 4.89 at month 3 compared to baseline, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eMany prostates anatomic characteristics have been proven to be correlated with the severity of LUTS, such as the PV, translation zone volume, and prostatic urethral angulation\u003csup\u003e\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e. However, the pathogenic mechanism of LUTS is complicated; in addition to prostatic enlargement, functional or structural abnormalities of the bladder neck may also contribute to LUTS\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e. As reported by Chia et al., when the enlargement of the prostatic median lobe causes protrusion from the base of the bladder, the protruded portion of the prostate will form a \u0026ldquo;ball-valve\u0026rdquo; type of structure, resulting in obstruction of the bladder neck\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. Thus, patients with a large IPP may be more likely to have bladder outlet obstruction due to protrusion of the prostate, which changes the form of the bladder neck\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e. On the other hand, previous studies have shown that the IPP is a strong predictor of TWOC outcome, especially when it exceeds 10 mm, and nearly 70%-87% of patients have an unsuccessful TWOC\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e,\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e. Our results have proven that when the IPP is larger than 10.25 mm (the best IPP cutoff to predict TWOC failure), 78% of AUR patients have an unsuccessful TWOC; these results are similar to the findings above. Additionally, our previous study found that the BNA could also reflect morphological changes of the bladder neck; the larger the BNA is, the more severe the disruption of the bladder neck\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eMany factors can affect the BNA through damage to the structure of the bladder neck, such as the volume of urinary retention, abnormal tension of the bladder neck smooth muscles, and enlargement of the prostatic anterior or lateral lobe. However, when the prostatic middle lobe protrudes from the bladder base, enlargement of the prostate squeezes the funnel structure of the bladder neck, causing elevation of the internal urethral orifice and flipping of the bladder neck wall outward, especially in AUR patients, the BNA was significantly correlated with IPP.\u003c/p\u003e \u003cp\u003eThere is still no consensus on the pathogenesis of AUR. Previous studies have established that large PV and IPP increase the risk of AUR and even cause TWOC failure\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e,\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e. We agree with the conclusion above. Our results showed that in patients with unsuccessful TWOC, the PV, IPP, and BNA were significantly larger than those in patients with successful TWOC. Moreover, ROC curve analysis showed that the BNA was more accurate than PV and IPP in predicting unsuccessful TWOC at the optimal cutoff of 89.94\u0026deg; (sensitivity\u0026thinsp;=\u0026thinsp;0.75, specificity\u0026thinsp;=\u0026thinsp;0.84).\u003c/p\u003e \u003cp\u003e In the present study, α-blocker was orally administered before TWOC in the patients with AUR, as recommended in the AUA guidelines. However, the efficacy of α-blocker to improve the outcome of TWOC is still controversial. As reported by Shah et al., oral α-blocker did not improve the outcome of TWOC or reduce the risk of recurrent urinary retention. A potential explanation for this discrepancy is that patients with large BNAs and IPPs may be nonresponsive to therapy with α-blocker or TWOC; when the mean IPP or BNA in the cohort is large, the α-blocker effect is limited, resulting in a decreased success rate of TWOC. In our study, the failure rate of TWOC was 48% in the AUR group; however, in the group with IPPs larger than 10.24 mm or BNAs larger than 89.94\u0026deg;, the unsuccessful rates of TWOC were 78% and 83%, respectively. With the progression of BPH, the muscle bundles of the bladder neck will gradually be replaced by collagenous tissue\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e. Unlike the dynamic obstruction caused by the unusual tone of smooth muscle, which can be relaxed with receptor antagonists, the fibrotic bladder neck is less likely to respond to α-blockers, and the large BNA, caused by the lower elasticity of the degenerative bladder neck, is unlikely to change after TWOC. Thus, the reduction of the funneling effect due to disruption of the funnel-shaped bladder neck will not improve. Without the catheter, more pressure is still required to open the internal urethral orifice to begin voiding, and according to the Reynolds Eq.\u0026nbsp;2\u003csup\u003e4\u003c/sup\u003e, the high initial urine flow speed, due to the higher pressure, will cause irregular turbulence and dyskinetic movement during urination. Hence, this subset will benefit from surgical intervention.\u003c/p\u003e \u003cp\u003eTraditionally, the first-line treatment for LUTS is medical therapy, combination therapy significantly improves the IPSS, compared to a placebo, at month 3\u003csup\u003e6\u003c/sup\u003e. In the present study, the correlation between BNA and IPP in the combination therapy group was weaker than that in the AUR group (R\u0026thinsp;=\u0026thinsp;0.372 vs. 0.581, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and the ROC analysis showed that the best cutoff for BNA to predict the failure of medical therapy was 75.85\u0026deg; (sensitivity was 0.78 and specificity was 0.87). When the patient\u0026rsquo;s BNA was larger than 75.85\u0026deg;, the improvement in IPSS was less than that in those with a small BNA. In addition, in the large BNA group, the late improvement in IPSS at months 9 and 12 may result from patients undergoing surgery dropping out of the statistics, this did not mean the improvements were deferred. By inhibiting the conversion of testosterone to dihydrotestosterone in prostatic stromal cells, 5-ARI reduces the stimulating effect of androgen on glandular epithelial cells, causing a decrease in PV\u003csup\u003e25\u003c/sup\u003e; however, the lower dihydrotestosterone may not reverse the fibrosis of the degenerate bladder neck, and due to the absence of stromal cells, the protrusion of the prostatic middle lobe may be insensitive to dihydrotestosterone\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e; thus, the effect of combination therapy was poor in patients with large BNA.\u003c/p\u003e \u003cp\u003eAfter the patient was converted to a surgical intervention, the improvement in IPSS was significant regardless of BNA; the resection of the prostate formed an artificial funnel-shaped structure that increase the funnel effect and removed the obstruction (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). Such improvement in urination may not be achieved with medical therapy. However, there were 3 patients, both with small PVs and large BNAs (the mean PV and BNA were 26.97 ml and 92.71\u0026deg;), who needed to be retreated due to bladder neck stenosis, which may be related to overresection of the degenerated bladder neck. A prophylactic bladder neck incision could be considered to reduce the incidence\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e, but more data is still needed to conduct a meaningful analysis.\u003c/p\u003e \u003cp\u003eThere are some limitations that need to be mentioned. Although both the BNA and IPP can be easily measured on the same sagittal ultrasonographic image, in the present study, the measurement of anatomical factors was performed by TRUS, which is invasive; thus, further study should compare the accuracy of measurements obtained with transabdominal ultrasound and TRUS. On the other hand, the measurement was performed in the resting state, but the form of the bladder neck may change during micturition.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn aging men with BPH/LUTS, a larger bladder neck angle emerges as an anatomical aging marker associated with both TWOC failure after AUR and a poorer symptomatic response to combination therapy. Incorporating BNA into the evaluation of older patients may improve risk stratification and support earlier, individualized intervention to prevent functional decline.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eThis study was conducted in accordance with the ethical principles of the Declaration of Helsinki, and approved by the Ethics Committee of Jinan University. Both patients and controls provided written informed consent.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eThe datasets generated and used in this study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003eNone.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contribution\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by YL, RZ, YYL, YHW, LSZ, YMZ. Project administration, review of the manuscript was performed by JH. RZ reviewed the pathological result of biopsies. In the perspective of urology, YMZ made the supervision, project administration, review of the manuscript. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u003c/strong\u003e Not applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eDevlin CM, Simms MS, Maitland NJ. Benign prostatic hyperplasia - what do we know? BJU Int. 2021; 127:389-399. \u003c/li\u003e\n\u003cli\u003eLerner LB, McVary KT, Barry MJ, et al. Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA GUIDELINE PART II-Surgical Evaluation and Treatment. J Urol. 2021; 206:818-826.\u003c/li\u003e\n\u003cli\u003eRassweiler J, Teber D, Kuntz R, et al. Complications of transurethral resection of the prostate (TURP)--incidence, management, and prevention. Eur Urol. 2006; 50:969-79.\u003c/li\u003e\n\u003cli\u003eClifford GM, Farmer RD. Medical therapy for benign prostatic hyperplasia: a review of the literature. Eur Urol. 2000; 38:2-19.\u003c/li\u003e\n\u003cli\u003eMcConnell JD, Bruskewitz R, Walsh P, et al. The effect of finasteride on the risk of acute urinary retention and the need for surgical treatment among men with benign prostatic hyperplasia. Finasteride Long-Term Efficacy and Safety Study Group. N Engl J Med. 1998; 338:557-63.\u003c/li\u003e\n\u003cli\u003eRoehrborn CG, Siami P, Barkin J, et al. The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study. Eur Urol. 2010; 57:123-31. \u003c/li\u003e\n\u003cli\u003eJacobsen SJ, Jacobson DJ, Girman CJ, et al. Natural history of prostatism: risk factors for acute urinary retention. J Urol. 1997; 158:481-7. \u003c/li\u003e\n\u003cli\u003eTaube M, Gajraj H. Trial without catheter following acute retention of urine. Br J Urol. 1989; 63:180-2.\u003c/li\u003e\n\u003cli\u003eMcNeill SA, Hargreave TB. Alfuzosin once daily facilitates return to voiding in patients in acute urinary retention. J Urol. 2004; 171:2316-20. \u003c/li\u003e\n\u003cli\u003eShah T, Palit V, Biyani S, et al. Randomised, placebo controlled, double blind study of alfuzosin SR in patients undergoing trial without catheter following acute urinary retention. Eur Urol. 2002; 42:329-32.\u003c/li\u003e\n\u003cli\u003eTubaro A, La Vecchia C. The relation of lower urinary tract symptoms with life-style factors and objective measures of benign prostatic enlargement and obstruction: an Italian survey. Eur Urol. 2004; 45:767-72.\u003c/li\u003e\n\u003cli\u003eTan YH, Foo KT. Intravesical prostatic protrusion predicts the outcome of a trial without catheter following acute urine retention. J Urol. 2003; 170:2339-41.\u003c/li\u003e\n\u003cli\u003eLee LS, Sim HG, Lim KB, et al. Intravesical prostatic protrusion predicts clinical progression of benign prostatic enlargement in patients receiving medical treatment. Int J Urol. 2010; 17:69-74. \u003c/li\u003e\n\u003cli\u003eChia SJ, Heng CT, Chan SP, et al. Correlation of intravesical prostatic protrusion with bladder outlet obstruction. BJU Int. 2003; 91:371-4. \u003c/li\u003e\n\u003cli\u003eLi Y, Chen Z, Zeng R, et al. Bladder Neck Angle Associated with Lower Urinary Tract Symptoms and Urinary Flow Rate in Patients with Benign Prostatic Hyperplasia. Urology. 2021; 158:156-161. \u003c/li\u003e\n\u003cli\u003eVenrooij GE, Boon TA. The value of symptom score, quality of life score, maximal urinary flow rate, residual volume and prostate size for the diagnosis of obstructive benign prostatic hyperplasia: a urodynamic analysis. J Urol. 1996; 155:2014-8. \u003c/li\u003e\n\u003cli\u003eOreste M, Giuseppe PG, Gianna P, et al. Between-subject variations of transition zone epithelial volume and serum PSA levels in men with benign prostatic hyperplasia. World J Urol. 2010; 28:379-83.\u003c/li\u003e\n\u003cli\u003eShim M, Bang WJ, Oh CY, et al. Correlation between prostatic urethral angulation and symptomatic improvement after surgery in patients with lower urinary tract symptoms according to prostate size. World J Urol. 2020; 38:1997-2003.\u003c/li\u003e\n\u003cli\u003eAbrams P, Chapple C, Khoury S, et al. Evaluation and treatment of lower urinary tract symptoms in older men. J Urol. 2009; 181:1779-87.\u003c/li\u003e\n\u003cli\u003eFranco G, De Nunzio C, Leonardo C, et al. Ultrasound assessment of intravesical prostatic protrusion and detrusor wall thickness--new standards for noninvasive bladder outlet obstruction diagnosis? J Urol. 2010; 183:2270-4.\u003c/li\u003e\n\u003cli\u003eMariappan P, Brown DJ, McNeill AS. Intravesical prostatic protrusion is better than prostate volume in predicting the outcome of trial without catheter in white men presenting with acute urinary retention: a prospective clinical study. J Urol. 2007; 178:573-7.\u003c/li\u003e\n\u003cli\u003eYoon PD, Chalasani V, Woo HH. Systematic review and meta-analysis on management of acute urinary retention. Prostate Cancer Prostatic Dis. 2015; 18:297-302.\u003c/li\u003e\n\u003cli\u003eHinata N, Miyake H, Murakami G, Abe S, Fujisawa M. Bladder Neck Muscle Degeneration in Patients with Prostatic Hyperplasia. J Urol. 2016; 195:206-12.\u003c/li\u003e\n\u003cli\u003eMartinez-Borges AR. Turbulent urinary flow in the urethra could be a causal factor for benign prostatic hyperplasia. Med Hypotheses. 2006; 67:871-5. \u003c/li\u003e\n\u003cli\u003eMcConnell JD, Bruskewitz R, Walsh P, et al. The effect of finasteride on the risk of acute urinary retention and the need for surgical treatment among men with benign prostatic hyperplasia. Finasteride Long-Term Efficacy and Safety Study Group. N Engl J Med. 1998; 338:557-63.\u003c/li\u003e\n\u003cli\u003eHirayama K, Masui K, Hamada A, et al. Evaluation of Intravesical Prostatic Protrusion as a Predictor of Dutasteride-Resistant Lower Urinary Tract Symptoms/Benign Prostatic Enlargement With a High Likelihood of Surgical Intervention. Urology. 2015; 86:565-9. \u003c/li\u003e\n\u003cli\u003eRassweiler J, Teber D, Kuntz R, et al. Complications of transurethral resection of the prostate (TURP)--incidence, management, and prevention. Eur Urol. 2006; 50:969-79.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Prostate, Bladder Neck Angle, Lower Urinary Trac Symptoms, Acute Urinary Retention, Ultrasonography","lastPublishedDoi":"10.21203/rs.3.rs-8703855/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8703855/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003ePurpose\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTo determine the predictive value of bladder neck angle (BNA) for trial without catheter (TWOC) following acute urinary retention (AUR) due to benign prostatic hyperplasia (BPH), and to evaluate its role in predicting response to combination therapy in patients with lower urinary tract symptoms (LUTS).\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eOutpatients presenting with bothersome LUTS or acute urinary retention (AUR) due to benign prostatic hyperplasia were included in the cohort. The prostate volume, intravesical prostatic protrusion, BNA, and postvoid residual volume were recorded. In patients with AUR, TWOC was performed after 2 weeks of alpha-blocker therapy; those with LUTS received alpha-blockers and 5-alpha reductase inhibitors for 12 months. Surgery was recommended for patients who experienced failure of conservative treatment. The uroflowmetry and International Prostate Symptom Score (IPSS) changes were assessed from baseline to 12 months after treatment.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eIn the efficacy analysis, 66 patients with AUR were recruited, and 32 patients (48.5%) experienced unsuccessful TWOC. The AUC for BNA to predict unsuccessful TWOC was 0.855 (95% CI 0.76\u0026ndash;0.94), and for intravesical prostatic protrusion, the AUC was 0.794 (95% CI 0.68\u0026ndash;0.91). In 335 patients with LUTS, from baseline to month 3, the change in IPSS after combination therapy was \u0026minus;\u0026thinsp;2.17 and \u0026minus;\u0026thinsp;4.89 in patients with large and small BNAs, respectively.\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusions\u003c/b\u003e\u003c/p\u003e \u003cp\u003eBNA is a promising anatomical predictor of TWOC outcome in AUR and may help identify LUTS patients who are likely to experience greater benefit from combination therapy. Incorporating BNA into clinical assessment may improve risk stratification and treatment planning in BPH management.\u003c/p\u003e","manuscriptTitle":"Bladder neck angle as an anatomical predictor of conservative treatment failure and the need for surgery in benign prostatic hyperplasia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-13 11:51:52","doi":"10.21203/rs.3.rs-8703855/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-21T09:18:06+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"328246213237188241263695209409630089316","date":"2026-04-13T18:34:42+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T07:21:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"122842458533688928605645906955234916989","date":"2026-04-11T14:21:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"237656624948910677154974513683829921706","date":"2026-02-12T11:54:06+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-11T21:06:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"274863058343331458296132182567791757085","date":"2026-02-10T11:15:11+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-08T09:26:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-30T02:24:43+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-29T17:02:36+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Urology","date":"2026-01-26T21:04:23+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"9491fc05-67a3-4592-8f7e-a67116d0c05f","owner":[],"postedDate":"February 13th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-12T22:23:17+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-13 11:51:52","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8703855","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8703855","identity":"rs-8703855","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}