Bladder neck obstruction (BNO) is characterized by narrowing at the junction between the urinary bladder and urethra, resulting in impaired urinary flow and associated lower urinary tract symptoms (LUTS). This condition predominantly affects men but is occasionally observed in women [1]. Patients typically present with urinary hesitancy, weak or interrupted stream, sensation of incomplete emptying, and increased risk of urinary tract infections (UTIs), which significantly diminish quality of life [2,3].

The bladder neck serves a crucial physiological function in regulating urine passage, with smooth muscle fibers influenced by the autonomic nervous system, particularly α-adrenergic receptors that modulate sphincter tone. When obstruction occurs, progressive complications may develop, including detrusor overactivity, urinary retention, and in severe cases, bladder decompensation with renal function impairment [4,5].

Management approaches vary according to obstruction severity. Medical therapy using α-adrenergic blockers such as tamsulosin effectively improves symptoms by relaxing the bladder neck musculature. However, when pharmacological treatment proves ineffective, surgical intervention through bladder neck incision (BNI) becomes necessary to restore normal urine flow [6].

It is essential to differentiate BNO from urethral stricture, as both present with similar clinical manifestations but require different management strategies [7]. BNO etiology is multifactorial, with common causes including post-surgical scarring following urological procedures [8], radiation therapy for pelvic malignancies [9], hormonal changes particularly estrogen deficiency in postmenopausal women, and anatomical alterations following multiple vaginal deliveries [10]. Traumatic injury and prolonged catheterization also contribute significantly to the development of bladder neck stenosis [11].

Female bladder outlet obstruction (FBOO) remains considerably under-researched, often underdiagnosed and misclassified due to symptom overlap with other lower urinary tract dysfunctions [14]. Despite endoscopic bladder neck incision emerging as a promising minimally invasive approach [15], standardized diagnostic criteria and treatment protocols for FBOO remain poorly defined compared to male BNO.

This research aims to address this knowledge gap by evaluating BNI efficacy and safety in female patients with bladder outlet obstruction, assessing urodynamic parameters, symptom relief, and postoperative complications to contribute toward developing standardized guidelines for female BNO management [16].

OBJECTIVES:

1. To evaluate the long-term outcomes of bladder neck incision (BNI) for bladder neck obstructions in women.
2. To find out the incidence of various cases of female bladder outlet obstruction
3. To identify the post-operative complications in different cases of female bladder outlet obstruction

This study is a hospital-based prospective observational study which was conducted at S.N. Medical College, Agra, over 12 months (January 2023 to December 2024). Fifty female patients aged 18-75 years with bladder outlet obstruction were recruited using consecutive sampling after obtaining informed consent.

To evaluate long-term outcomes of BNI, patients underwent comprehensive follow-up evaluations at 6 months, 1 year, and 1.5 years post-surgery using a validated ICIU-LUTS questionnaire, uroflowmetry parameters (voided volume). Quality of life metrics were also documented at each follow-up.

To determine the incidence of various cases of female bladder outlet obstruction, a detailed classification of ethology was performed based on preoperative assessments, including clinical examinations, urodynamic studies, and cystoscopy findings. Cases were categorized as primary bladder neck obstruction, iatrogenic stenosis, or other identifiable causes.

Post-operative complications were systematically recorded and classified according to the Clavien-Dindo classification system. Specific complications monitored included urinary incontinence, urinary tract infections, recurrent obstruction, and need for re-intervention. Time-to-complication analysis was performed using Kaplan-Meier estimates.

All patients underwent standardized BNI under general/spinal anesthesia using various techniques (one, two, or three-slit approaches). Data analysis employed descriptive statistics, comparative pre-post analyses, and multivariate analysis to identify predictors of successful outcomes and complications with significance set at p<0.05.

Table 1: Severity of BOO

The severity of bladder outlet obstruction was classified into moderate and severe categories. Among the 50 patients studied, 36 (72%) were classified as having severe obstruction, while the remaining 14 (28%) had moderate obstruction.

Table 2: Follow-up Quality of Life (QoL) Score and Postoperative Urinary Residual Volume

Change in quality of life (QoL) over time following bladder neck incision was noted.  The mean QoL scores at 6 months, 1 year, and 1.5 years were 11.94 ± 2.68, 10.58 ± 2.34, and 9.56 ± 1.83, respectively, indicating a progressive improvement in patient-reported outcomes and changes in quality of life (QoL) over time following bladder neck incision

The mean residual volume was 25.02 ± 10.08 mL, with values ranging from 10 mL to 40 mL across the study sample (N = 50).

Table 3: Patient Satisfaction Scores and Postoperative Voiding Difficulty

Patient satisfaction scores were recorded postoperatively to evaluate subjective outcomes following bladder neck incision. Out of 50 patients, 42% (n=21) reported low satisfaction, falling within the score range of 1–3. An equal proportion, 42% (n=21), expressed high satisfaction with scores ranging from 7 to 10. Meanwhile, 16% (n=8) of the patients reported moderate satisfaction, scoring between 4 and 6.

Table 4: Association between Follow-up Complications and Severity

       *statistically significant

There was no significant association between complication type and severity at 6 months and 1 year, a significant correlation emerged at 1.5 years, implying that long-term follow-up more accurately reflects the true relationship between complication status and its severity.

Table 5: Comparison of Preoperative and Postoperative Objective and Subjective Indices

The ANOVA analysis demonstrated statistically significant improvements in all key postoperative parameters following bladder neck incision (BNI). The mean urinary flow rate (Qmax) increased from 7.2 ± 3.9 mL/s preoperatively to 26.1 ± 5.2 mL/s at 18 months, with an F-statistic of 172.74 and a p-value < 0.0001, indicating a highly significant enhancement in voiding efficiency. Similarly, the postvoid residual volume (PVR) decreased markedly from 162 ± 75 mL to 20 ± 7 mL over the same period, with an F-statistic of 158.5 and a p-value < 0.0001, confirming improved bladder emptying. Quality of life scores (QOLS) also showed significant improvement, reducing from 5.4 ± 1.7 to 1.9 ± 1.1, supported by an F-statistic of 107.09 and a p-value < 0.0001. These findings collectively highlight the long-term effectiveness of BNI in improving urinary function and enhancing patient-reported outcomes.

The present study comprehensively evaluated the long-term outcomes of bladder neck incision (BNI) in women with bladder outlet obstruction (BOO), with specific focus on changes in quality of life (QoL), voiding function, postoperative complications, and procedure-specific outcomes over an 18-month follow-up period.

Female BNO is an idiopathic condition resulting in inadequate relaxation of the bladder neck during voiding. Women with BNO typically present with obstructive voiding symptoms. While multiple techniques for BNI have been described, no standard exists regarding the exact incision location, number of incisions, or ideal technology. As BNI in women may lead to serious complications like vesicovaginal fistula (VVF) or incontinence, it is crucial to perform the procedure with extreme care.

In this study of 50 female patients undergoing bladder neck incision (BNI) for bladder outlet obstruction (BOO), 72% had severe obstruction and 28% had moderate obstruction at baseline. This distribution indicated that a majority of the patients presented with a more advanced stage of bladder outlet obstruction at the time of surgical intervention.

Postoperative outcomes showed a consistent improvement in quality of life (QoL), with mean QoL scores declining from 11.94 at 6 months to 9.56 at 1.5 years, indicating symptom relief. In a study by Zhang et al., bladder neck incision (BNI) in 84 women with primary BOO led to significant clinical improvements and improved QoL but was associated with notable complications, including vesicovaginal fistula (3.6%), stress urinary incontinence (4.7%), and urethral stricture (3.6%). In contrast, the present study reported fewer complications, likely due to a more conservative surgical technique, typically limiting the incision to a single site, thereby minimizing sphincter damage and preserving continence.

The mean post-void residual volume was 25.02 ± 10.08 mL, suggesting effective bladder emptying post-surgery. These findings indicated that most patients achieved adequate bladder emptying postoperatively, as none exceeded the clinically significant threshold for urinary retention. This supported the functional success of the surgical procedure in improving postoperative voiding efficiency.

Patient satisfaction was split, with 42% reporting high satisfaction (scores 7–10), 42% low satisfaction (scores 1–3), and 16% moderate. This distribution suggests that while a significant number of patients experienced favorable outcomes and were highly satisfied with the procedure, an equally large group reported dissatisfaction. These findings highlight the variability in patient-reported outcomes and underscore the importance of careful patient selection, preoperative counseling, and long-term follow-up to improve satisfaction rates and overall clinical outcomes.

Complication rates decreased over time: 48% had no complications at 6 months, increasing to 86% at 1.5 years. This indicates the procedure’s long-term safety and effectiveness in reducing postoperative issues. A significant association between complication type and severity emerged only at 1.5 years, underscoring the importance of long-term follow-up to assess true surgical outcomes. Lee et al. [17] also evaluated the 2 μm holmium laser and reported similar benefits, including reduced bleeding and improved patient recovery (shorter hospital stays and lower discomfort levels)

In our study, 14 patients underwent one-slit, 13 underwent two-slit, 6 underwent three-slit, and 17 underwent transurethral BNI. It revealed that the transurethral and one-slit procedures were associated with the lowest complication rates over time. At 6 months, 64.7% of transurethral patients were complication-free, outperforming one-, two-, and three-slit groups. By 1 year and 1.5 years, all patients in the transurethral and one-slit groups remained free of complications, while moderate complications persisted in the two- and three-slit groups, especially the three-slit group, where 66.7% had complications at 1.5 years. These findings suggest that multiple-slit techniques, particularly the three-slit approach, are linked to higher long-term complication rates, whereas transurethral and one-slit methods offer better safety profiles.Chan et al.(88) found that robotic-assisted BNI offered better precision and recovery but at a higher cost. In comparison, our more affordable approach yielded similarly favorable outcomes, demonstrating that effective results can be achieved without expensive technology.

Bladder neck incision significantly improved patient outcomes, with Qmax increasing from 7.2 to over 26 mL/s and postvoid residual volume dropping from 162 to 20 mL by 18 months. The Sharifiaghdas et al.(18) study indicated a median postoperative maximum flow rate (Qmax) of 11 mL/sec (range 9.1–16), but the author noted that the incision depth might have been insufficient to achieve maximal benefit. Quality of Life Scores also improved markedly, indicating better urinary function and overall patient well-being over time

The present study established that bladder neck incision (BNI) is a safe, effective, and durable treatment for women with primary bladder neck obstruction. It resulted in progressive improvement in quality of life, effective bladder emptying, and generally positive patient satisfaction. Most patients had severe obstruction. Complication rates significantly declined over time, especially in those treated with transurethral or single-slit techniques. These findings support BNI as a reliable long-term intervention with favorable clinical and functional outcomes.

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