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Table of Contents
ORIGINAL ARTICLE
Year : 2019  |  Volume : 30  |  Issue : 6  |  Page : 266-271

Therapeutic Efficacy and Quality of Life Improvement in Women with Detrusor Underactivity Following Transurethral Incision of the Bladder Ne


Department of Urology, Hualien Tzu Chi General Hospital and Buddhist Tzu Chi Medical Foundation, and Tzu Chi University, Hualien, Taiwan

Date of Submission13-Jun-2019
Date of Decision13-Aug-2019
Date of Acceptance04-Sep-2019
Date of Web Publication23-Dec-2019

Correspondence Address:
Dr. Hann-Chorng Kuo
Department of Urology, Hualien Tzu Chi General Hospital and Buddhist Tzu Chi Medical Foundation, and Tzu Chi University, No. 707, Section 3, Chung Yang Road, Hualien
Taiwan
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/UROS.UROS_39_19

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  Abstract 


Aims: To investigate the effects of transurethral incision of the bladder neck (TUI-BN) on long-term outcomes and quality of life (QoL) improvements in women with detrusor underactivity (DU) refractory to standard medical treatment. Materials and Methods: Data were retrieved for female patients with treatment-refractory DU who underwent TUI-BN between 2007 and 2018. Urodynamic parameters were measured at baseline and follow-up and were analyzed for surgical outcome. Patients who were capable of spontaneously voiding with a voiding efficiency (VE) of ≥50% with or without the aid of abdominal pressure were considered to have achieved satisfactory outcomes. Changes in self-reported QoL were measured based on the International Prostate Symptom Score QoL (IPSS-QoL), and treatment improvements were measured based on the global response assessment (GRA) index. Moreover, the voiding statuses of patients before and after TUI-BN were compared. Results: Overall, 82 women, with a mean age of 60.8 ± 17.9 years (range 12–102), were included. Most patients experienced chronic urinary retention or large postvoid residual (PVR) urine. Median follow-up period was 5 years (range 1–12). Following TUI-BN, 40 (48.8%) patients achieved satisfactory outcomes, with a mean GRA of 1.4 ± 0.93. Mean maximum flow rate, voided volume, PVR volume, VE, and IPSS-QoL were all significantly improved. Among all patients, 50 (61%) were subsequently able to spontaneously void with or without the aid of abdominal pressure without the need for catheterization. Indwelling catheters were required in 19 (23.2%) patients at baseline and in 5 (6.1%) following TUI-BN (P < 0.01). Moreover, 5 (6.1%) patients developed stress urinary incontinence and 2 (2.4%) experienced vesicovaginal fistulae following TUI-BN procedures, all of whom recovered satisfactorily after treatment. Conclusions: TUI-BN is an effective procedure for reducing the bladder outlet resistance and improving VE and QoL. Moreover, the procedure is durable with an acceptable incidence of complications.

Keywords: Detrusor underactivity, female, quality of life, therapeutic efficacy, transurethral incision of bladder neck


How to cite this article:
Lee YK, Kuo HC. Therapeutic Efficacy and Quality of Life Improvement in Women with Detrusor Underactivity Following Transurethral Incision of the Bladder Ne. Urol Sci 2019;30:266-71

How to cite this URL:
Lee YK, Kuo HC. Therapeutic Efficacy and Quality of Life Improvement in Women with Detrusor Underactivity Following Transurethral Incision of the Bladder Ne. Urol Sci [serial online] 2019 [cited 2020 Jan 26];30:266-71. Available from: http://www.e-urol-sci.com/text.asp?2019/30/6/266/273878




  Introduction Top


Detrusor underactivity (DU) is a common urological issue among the elderly. The clinical symptoms of DU include slow stream, large postvoid residual (PVR) urine, chronic urinary retention, and subsequent urinary tract infection (UTI), all of which negatively affect the patient's quality of life (QoL) and threaten their personal health. The International Continence Society (ICS) has defined DU as a contraction with reduced strength and/or duration, resulting in prolonged bladder emptying and/or failure to achieve complete bladder emptying within a normal time span.[1] DU pathophysiology has not yet been completely elucidated; however, it may be related to aging, bladder outlet obstruction (BOO), diabetes mellitus, and neurogenic etiologies.[2]

Treatment options for DU generally focus on increasing bladder contractility, increasing bladder sensation, or decreasing BOO.[3] First-line medical treatments for DU include parasympathomimetics (e.g., bethanechol) or cholinesterase inhibitors (e.g., distigmine bromide) administered with or without alpha-blockers.[4] However, a recent systemic review failed to identify any effective medical modalities for DU.[5]

A poorly relaxed urethral sphincter may be among the causes of DU, by causing BOO and incomplete bladder emptying.[6],[7] A previous study suggested that a poorly relaxed urethral sphincter might provide a guarding reflex and inhibit the effective detrusor contraction.[8] Therefore, enhancing urethral relaxation is an important therapeutic goal in patients with DU. The recovery of detrusor contractility has previously been demonstrated following the injection of 50–100 units of botulinum toxin A into the urethral sphincter in patients with low detrusor contractility.[9] However, to achieve greater therapeutic effects in patients with both DU and dysfunctional voiding, repeated injections are necessary.[10] Therapeutic effects of the urethral injection of botulinum toxin A were observed to last 3–6 months;[11] therefore, the cost-effectiveness of such treatments should be carefully considered.

Endoscopic bladder neck (BN) incision for the treatment of patients with BN dysfunction was first reported by Turner-Warwick in 1973.[12] A satisfactory surgical outcome of transurethral incision of the BN (TUI-BN) for female DU patients with urinary retention has previously been reported.[13] Moreover, TUI-BN is effective in regaining spontaneous voiding function in patients with spinal cord injury and detrusor sphincter dyssynergia.[14] During videourodynamic studies, we observed that about 20% of women with DU and urine retention have poor bladder-neck opening when they attempt to void with abdominal straining. We postulated that these women with DU and urine retention could have bladder-neck obstruction and that TUI-BN could effectively improve voiding efficiency (VE). In the present study, we evaluate long-term therapeutic efficacy and QoL in women with DU following TUI-BN.


  Materials and Methods Top


In the present retrospective study, we analyzed clinical data from female patients who underwent TUI-BN for DU between 2007 and 2018. All patients included in the study had experienced chronic urinary retention or large PVR volume (≥200 mL) for at least 6 months. The conventional medical treatments had all failed in these patients, such as alpha-adrenergic blocker and/or bethanechol for at least 3 months. Complete videourodynamic studies (VUDS) were performed before surgery, following the guidelines and recommendations of the ICS.[15],[16] DU was diagnosed based on the ICS definition. A nonopening BN could be observed on VUDS when the patient attempted to void via abdominal straining. Patients with pelvic organ prolapse, severe systemic disease, and Eastern Cooperative Oncology Group Performance statuses of >3 were excluded from the study. Furthermore, patients who had previously received lower urinary tract surgery, such as anti-incontinence procedures, were excluded.

Routine history taking and physical examinations were performed before TUI-BN. Voiding methods for each patient were recorded before surgery. The following baseline urodynamic parameters were collected during VUDS: the first sensation of bladder filling, fullness sensation, cystometric bladder capacity, maximum flow rate (Qmax), voided volume (VV), PVR volume, maximal intravesical pressure, and maximal detrusor pressure at Qmax (Pdet. Qmax). VE was calculated as VV/total bladder capacity × 100%.[17] The International Prostate Symptom Score (IPSS-QoL) was used to evaluate the impact of lower urinary tract symptoms on the patient's activities of daily living before and after TUI-BN.[18]

TUI-BN was performed under intravenous general anesthesia. The procedure used an adult transurethral resectoscope and a diathermy electrode with a 110-W cutting current. Following full bladder distension, two incisions were initiated at the 5 O'clock and 7 O' clock positions of the BN. After the diathermy incision deep into the BN smooth muscle, the muscle was completely interrupted until serosa could be visualized. The incision line was terminated before reaching the urethral sphincter, measuring approximately 1–1.5 cm in length. A Foley catheter was indwelled for two nights after surgery. A voiding trial was commenced after the removal of the Foley catheter, and uroflowmetry and PVR volume were checked. Clean intermittent catheterization (CIC) was recommended if PVR volume was noted to be >200 mL. Patients were requested to follow-up at outpatient clinics to track the voiding status, and a postoperative VUDS was performed 3 months after surgery. Additional procedures including repeat TUI-BN or the urethral sphincter injection of botulinum toxin A were suggested if the patient's VE remained <50% and incidences of a tight BN or narrow external urethral sphincter were noted during postoperative VUDS.

Patients were subsequently interviewed by telephone in March 2019. Information was collected regarding postoperative IPSS-QoL, current voiding status, and bladder management, and we evaluated patient satisfaction with TUI-BN using the global response assessment (GRA) index. The study was approved by the Ethics Committee of the Buddhist Tzu Chi General Hospital (IRB no. 100-06 obtained on January 27th, 2011). Written informed consent was waived owing to the retrospective nature of the study.

Preoperative and postoperative urodynamic parameters were compared using a paired t-test. Chi-square test was used to evaluate surgical success rate, complication rate, and voiding methods. P ≤ 0.05 was considered statistically significant. All statistical analyses were performed using the statistical package SPSS (version 20.0; SPSS, Chicago, IL, USA).


  Results Top


Overall, 82 women with DU who underwent TUI-BN were included in the present study. The mean age of the patients was 60.9 ± 17.9 years (range 12–102). The median follow-up period was 5 years (range 1–12). Of the 82 patients, 59 (72%) were considered to have a neurogenic etiology and 23 (28%) were considered idiopathic. Mean Pdet. Qmax before surgery was 5.27 ± 8.39 cm H2O. Among the patients, 42 (51.2%) showed acontractile detrusors (Pdet. Qmax = 0) on VUDS. In addition, 62 (70.6%) patients presented with large PVR volume (o200 mL) or chronic urinary retention, requiring CIC catheterization or an indwelling catheter to enable bladder emptying. Moreover, 38 patients presented with difficulty urinating, among whom 30 had a large PVR volume (o200 mL) and eight had a small PVR volume (<200 mL).

During a mean follow-up period of 56.7 (range 7–81) months, nine patients expired and five were lost to follow-up; however, we were able to trace their postoperative statuses from their most recent chart review. A satisfactory outcome was achieved in 40 (48.8%) patients. Mean GRA scale was 1.4 ± 0.93 following TUI-BN. Mean Qmax, VV, PVR volume, VE, and IPSS-QoL all significantly improved after TUI-BN, as shown in [Table 1]. Furthermore, 50 (60.9%) patients did not require a catheter and were capable of spontaneously voiding via abdominal straining. Long-term indwelling catheters were required in 19 (23.2%) patients before surgery, decreasing to 5 (6.1%) postoperatively, as shown in [Table 2]. No significant differences were observed between pre- and post-TUI-BN in terms of UTI incidence. Overall, 32 (39%) patients required additional procedures including repeat TUI-BN or an urethral injection of botulinum toxin A following first TUI-BN; 19 (59.4%) of these 32 patients were observed to have achieved satisfactory outcomes (VE ≥ 50%) during follow-up.
Table 1: Changes in urodynamic parameters before and after transurethral incision of the bladder neck

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Table 2: Voiding management before and after transurethral incision of the bladder neck (n=82)

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After considering all the procedures for voiding dysfunction, 59 (72%) of 82 patients achieved a satisfactory outcome and 5 (6.1%) patients developed stress urinary incontinence at 1 month to 3 years following TUI-BN, which was subsequently treated using pubovaginal sling procedures. In addition, 2 (2.4%) patients developed vesicovaginal fistulae during the TUI-BN procedure; in both cases, immediate transvaginal fistula repairs were performed without any urinary incontinence sequelae. Both patients had received multiple TUI-BN procedures (twice in one patient and four times in the other) to improve VE. Mild urgency or stress urinary incontinence during follow-up was observed in 12 (14.6%) patients, and these were effectively treated with medication, as shown in [Table 3].
Table 3: Complications of transurethral incision of the bladder neck

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  Discussion Top


The present study demonstrated that TUI-BN is safe and effective for female patients experiencing voiding dysfunction caused by DU. In this study, 49% of patients achieved a satisfactory outcome after a single TUI-BN procedure with a mean follow-up period of >5 years. Furthermore, 60.9% of patients were capable of spontaneously voiding via abdominal straining without the aid of a catheter to empty the bladder. Moreover, some patients with indwelling catheters or CIC before surgery were able to switch to self-voiding and/or CIC. CIC frequency was decreased and QoL was significantly improved following TUI-BN.

A previous study has shown that TUI-BN leads to a significant increase in mean Pdet. Qmax in patients with voiding dysfunction due to DU.[13] We observed a similar result in the present study. Although the change we observed in Pdet. Qmax was not significant, some patients did demonstrate increased detrusor contractility following TUI-BN [Figure 1]. Several studies have previously shown that men with DU are capable of recovering detrusor contractility after undergoing transurethral bladder outlet surgery.[19],[20] Both the BN and prostatic urethra are innervated by the sympathetic adrenergic nerves, potentially playing important roles in the guarding reflex of the micturition cycle.[21] Contraction of the urethral sphincter is known to inhibit bladder contraction.[22] The terminal nerves are at their greatest distribution at the 4 O'clock and 8 O'clock positions of the BN and proximal urethra.[23] Destruction of the BN and prostatic urethra in this region may interrupt the reflex circuit and terminate the sympathetic hyperactivity, thereby inhibiting detrusor contractility in the spinal cord. This effect could be observed in patients with idiopathic DU, who may be able to regain adequate detrusor contractility and resume spontaneous voiding.[24] This phenomenon was observed in patients with neurogenic DU, suggesting that TUI-BN may serve to trigger a micturition facilitating reflex.[4],[14] Some patients in the present study regained bladder contractility following TUI-BN, which may be a result of this therapeutic mechanism. In the remaining patients, detrusor muscle rehabilitation following the reduction of bladder outlet resistance may also result in the recovery of bladder contractility. A previous study using animal models demonstrated that functional recovery following bladder outlet surgery may be owing to the return of blood flow to the urinary bladder and recovery of cellular functions of the detrusor muscle.[25] Nevertheless, increased bladder contractility following TUI-BN might not be sufficient for sustained spontaneous voiding; thus, most patients still require the aid of abdominal straining to void.
Figure 1: Videourodynamic studies tracings from a 47-year-old woman who had been experiencing chronic urinary retention for 8 years. (a) Preoperative videourodynamic studies showed intact bladder sensation and detrusor underactivity, alongside an elevated bladder base. (b) At 4 days after transurethral incision of the bladder neck, detrusor contractility returned and the patient was able to void with maximum flow rate of 23 mL/s and no postvoid residual urine. However, high voiding pressure and narrow urethral sphincter were noted during videourodynamic studies, indicating that dysfunctional voiding remained, which may require further medical treatment

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The therapeutic effect of TUI-BN in women with DU has been reported in previous studies.[9],[13],[24] Notably, patients who were able to generate greater abdominal pressure were observed to achieve better outcomes following TUI-BN.[13] However, not all patients were able to achieve satisfactory outcomes after a single TUI-BN procedure. Urethral sphincter hypertonicity, dysfunctional voiding, pelvic floor muscle hyperactivity, or impaired bladder sensation may all potentially contribute to treatment failure.[4] In the present study, we observed that 32 (39%) patients received additional procedures after their first TUI-BN owing to the lack of satisfaction with the initial result. Currently, no standard indicators exist to suggest the optimal depth or length of cut to use during TUI-BN. We performed repeat TUI-BN procedures when a tight BN was detected on the postoperative VUDS. On the other hand, when an open BN but tight external urethral sphincter during voiding was detected, we administered injections of 100U of botulinum toxin A into the urethral sphincter to decrease urethral resistance and facilitate spontaneous voiding via abdominal straining.[9] Of the 32 patients, 19 who underwent additional procedures achieved satisfactory outcomes (VE ≥50%) at follow-up.

Perioperative complication rates for TUI-BN in the present study were of acceptable levels. Although five patients experienced stress urinary incontinence following TUI-BN, they were successfully treated with anti-incontinence procedures to resolve the problem. Most of these patients experienced an acontractile detrusor and impaired bladder sensation, and urinary incontinence generally occurred upon reaching bladder capacity. The 12 patients who experienced occasional urgency or stress urinary incontinence during follow-up were treated conservatively with antimuscarinics or beta three-agonists with or without pad protection. Moreover, two patients who developed vesicovaginal fistulae during repeat TUI-BN procedures underwent an immediate vesicovaginal fistula repair and recovered well without any urinary incontinence sequelae. These patients had both undergone multiple TUI-BN procedures (twice in one patient and four times in the other); therefore, when performing repeat TUI-BN procedures, incision sites should be carefully selected to avoid inadvertent injury to the thin underside of the vaginal wall.

Although women experiencing chronic urinary retention or large PVR volume can typically be managed using CIC, their QoL is unsatisfactory. Most of these patients must perform CIC at least three or four times a day, which may negatively impact their social lives. The ability to resume spontaneous voiding reduces the incidence of UTI by decreasing the frequency of CIC as well as helps increase the patient's sense of dignity and confidence in activities of daily living. Significant improvements in IPSS-QoL scores following TUI-BN were noted in this study. Reducing catheter use significantly improved patient QoL, whereas no significant differences were observed in the incidence of UTI. Taken together, these results reflect the clinical significance of TUI-BN in the treatment of female voiding dysfunction due to DU. Furthermore, the ability to return efficient detrusor contractility to patients encourages further interest in performing this minimally invasive procedure in women with DU.

There were some limitations to the present study. First, this was a retrospective study in a single center with a small number of patients. Second, the follow-up course was not well scheduled and might not be comprehensive. We used telephone interviews to collect questionnaire data, which may be associated with an interview bias. In addition, because the voiding dysfunctions of most patients in this study were highly complex and severe, with the patients being refractory to conventional treatments, a selection bias may also interfere with the study results. A prospective, randomized, controlled study with a large cohort is warranted in the future to confirm our findings on the effectiveness of TUI-BN in women with DU.


  Conclusions Top


TUI-BN is an effective procedure for the reduction of bladder outlet resistance, resulting in improved VE and QoL. In women for whom spontaneous urination without catheterization is a desired outcome, TUI-BN is a valuable therapeutic strategy. Moreover, the procedure is durable, with an acceptable incidence of complications.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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