Sacral nerve stimulation for treatment of refractory urinary urge incontinence. Sacral Nerve Stimulation Study Group.

PURPOSE: A prospective, randomized study was performed to evaluate sacral nerve stimulation for the treatment of refractory urinary urge incontinence. MATERIALS AND METHODS: Primary outcome variables were obtained from voiding diaries. After baseline evaluation candidates who satisfied inclusion criteria were enrolled into the study. Test stimulation results determined eligibility for randomization into a stimulation (treatment) or delay (control) group. The stimulation group included 34 patients who underwent implantation and were followed for 6 months. The delay group comprised 42 patients who received standard medical therapy for 6 months and then were offered implantation. The stimulation group completed a therapy evaluation test (on versus off) after 6 months. RESULTS: At 6 months the number of daily incontinence episodes, severity of episodes and absorbent pads or diapers replaced daily due to incontinence were significantly reduced in the stimulation compared to the delay group (all p<0.0001). Of the 34 stimulation group patients 16 (47%) were completely dry and an additional 10 (29%) demonstrated a greater than 50% reduction in incontinence episodes 6 months after implantation. Efficacy appeared to be sustained for 18 months. During the therapy evaluation test the group returned to baseline levels of incontinence when stimulation was inactivated. Urodynamic testing confirmed that sacral nerve stimulation did not adversely affect voiding function. Complications included implantable pulse generator site pain in 15.9% of the patients, implant site pain in 19.1% and lead migration in 7.0%. Surgical revision was required in 32.5% of patients with implants to resolve a complication. There were no reports of permanent injury or nerve damage. CONCLUSIONS: Sacral nerve stimulation is safe and effective in treating refractory urinary urge incontinence.     

QUALITY OF LIFE ASSESSMENT IN PATIENTS WHO UNDERGO SACRAL NEUROMODULATION IMPLANTATION FOR URGE INCONTINENCE: AN ADDITIONAL TOOL FOR EVALUATING OUTCOME

PURPOSE: We investigated the impact of sacral neuromodulation on quality of life and assessed the importance of quality of life for determining the success of sacral neuromodulation in patients with detrusor hyperactivity, including instability and hyperreflexia. We also compared it with parameters documented in a voiding diary. MATERIALS AND METHODS: From May 1998 to December 2000, 82 female and 31 male patients 17 to 79 years old (mean age 51.1) with urge incontinence (63), urgency/frequency (5), voiding disturbance (41) and pelvic pain (4) resistant to conservative treatment were enrolled in a national prospective registry after showing a positive response to percutaneous nerve evaluation testing. Of the patients 47 who were 32 to 79 years old (mean age 59.2) with urge incontinence due to detrusor instability and 16 who were 27 to 51 years old (mean age 51.5) with hyperreflexia were asked to complete a validated self-reporting incontinence domain specific quality of life questionnaire before, and 3, 6, 9, 12, 18, 24 and 36 months after implantation. RESULTS: Compared with baseline the quality of life index significantly improved at each followup, which strongly correlated with the decrease in the number of incontinence episodes. CONCLUSIONS: Evaluating quality of life may be an additional useful tool for assessing the results of sacral neuromodulation for urge incontinence. Our study confirms that sacral neuromodulation is effective therapy for urge incontinence that can have a positive effect on patient quality of life.     

The role of neuromodulation in the management of urinary urge incontinence

OBJECTIVE: To examine the benefit-risk profile of neuromodulation in treating refractory urinary urge incontinence and other voiding disorders. PATIENTS AND METHODS: The outcome measures from all patients in pivotal clinical trials who had undergone sacral nerve stimulation were analysed retrospectively. RESULTS: Neuromodulation was effective in several clinical studies; the response is durable and the benefit-risk profile good. CONCLUSION: Sacral nerve stimulation is becoming the standard of care for refractory overactive bladder and retention problems. The potential benefit of neuromodulation should be included in female urology and gynaecology training programmes.     

Long-term effectiveness of sacral nerve stimulation for refractory urge incontinence

OBJECTIVES: To evaluate the long-term efficacy of sacral nerve stimulation for refractory urinary urge incontinence. STUDY DESIGN AND METHODS: Urge incontinent patients qualified for surgical implantation of a neurostimulator system after trial screening with percutaneous test stimulation. Surgical implantation of the InterStim System (Medtronic Inc., Minneapolis, Minn., USA) was performed in cases where a >50% reduction in incontinence symptoms was documented during the 3- to 7-day test stimulation period. The InterStim System consists of an implantable pulse generator, a transforamenally placed quadripolar lead, and an extension that connects these two devices for unilateral stimulation of the S3 or S4 sacral nerve. Efficacy for 96 implanted patients was based on urinary symptom changes as quantified in voiding diaries collected at baseline and annually after surgical implantation. RESULTS: As compared to baseline, the group of 96 implanted patients demonstrated significant reductions in urge incontinent symptoms at an average of 30.8+/-14.8 (range 12-60) months with respect to the number of urge incontinent episodes per day, severity of leaking, and the number of absorbent pads/diapers replaced per day due to incontinence (all p<0.0001, respectively). Gender, pretreatment variables, and age were not found to be relevant factors that affected these results. 11 of the 96 patients underwent device explant due to lack of efficacy, pain or bowel dysfunction. These data were conservatively included in the efficacy results. No permanent injuries associated with the devices or therapy were reported. CONCLUSION: Sacral nerve stimulation is an effective treatment for refractory urge incontinence with sustained long-term benefit through an average of 30.8 months.     

Sacral root neuromodulation in the treatment of refractory urinary urge incontinence: a prospective randomized clinical trial

OBJECTIVES: To compare the effectiveness of sacral root neuromodulation with that of conservative management in ameliorating symptoms of refractory urinary urge incontinence and enhancing quality of life, to assess the objective response to neuromodulation as revealed by urodynamic testing, and to delineate the long-term outcomes of neuromodulation. METHODS: Forty-four patients with refractory urge incontinence were randomized to undergo neuromodulation with an implantable impulse generator (n = 21) or to continue their prior conservative management (n = 23). At 6 months the control group was eligible for crossover to implant. Patient evaluation included voiding diaries, quality of life questionnaires, urodynamic testing, and documentation of adverse events. Long-term follow-up evaluations were conducted at 6-month intervals up to 36 months. RESULTS: At 6 months mean leakage episodes, leakage severity and pad usage in the implant group were significantly lower by 88% (p < 0.0005), 24% (p = 0.047) and 90% (p < 0.0005), respectively, than the corresponding control group mean values. Improvements in leakage episodes and pad usage of >/=90% were attained by 75 and 85% of the implant group, respectively, but none of the control group. One third of implant patients, but none of the control patients, achieved >/=50% improvement in leakage severity. Over half of the implant patients (56%) were completely dry compared with 1 control patient (4%). Implant patients, but not control patients, exhibited significant improvement with respect to two quality of life measures. Neuromodulation resulted in increases of 220% (p < 0.0005) and 39% (p = 0.013), respectively, in urodynamically assessed bladder volume at first contraction and maximum fill. At 36 months the actuarial rate of treatment failure was 32.4% (95% CI, 17.0-56.0%). Adverse events most frequently involved pain at the implant site, and the incidence of serious complications was low. CONCLUSIONS: Neuromodulation is markedly more effective than conservative management in alleviating symptoms of refractory urge incontinence. Quality of life and urodynamic function are also improved by neuromodulation. The effects of neuromodulation are long-lasting, and associated morbidity is low.     

Chronic pudendal nerve neuromodulation in women with idiopathic refractory detrusor overactivity incontinence: results of a pilot study with a novel minimally invasive implantable mini-stimulator

AIMS: To assess the results of chronic pudendal nerve neuromodulation with a novel technique in a pilot study on women with idiopathic refractory detrusor overactivity incontinence. MATERIALS AND METHODS: A percutaneous screening test (PST) was performed in patients with urodynamically demonstrated detrusor overactivity incontinence. Such a test includes the performance of a cystometrogram without and with percutaneous pudendal nerve stimulation and is considered positive if stimulation results in a more than 50% increase in the bladder volume at the first involuntary detrusor contraction or the maximum cystometric capacity. Patients with a positive PST qualified for the implantation of a mini-neurostimulator with an integrated electrode, a so-called bion(R), adjacent to the pudendal nerve at Alcock's Canal. Five-day voiding-incontinence diaries were the main tool for the evaluation of therapy. RESULTS: A PST was performed in 14 women. Six patients responded positively and received a bion. The degree of incontinence decreased significantly in this group, which also included patients in whom sacral neuromodulation had failed. There were no severe adverse events. CONCLUSIONS: Chronic pudendal nerve stimulation may reduce the degree of detrusor overactivity incontinence, even in patients in whom sacral neuromodulation fails. Bion therapy is relatively simple and minimally invasive and is well tolerated by the patient.     

Neurostimulation for lower urinary tract voiding problems

In 1981, Tanagho and Schmidt introduced chronic electrical stimulation of the sacral spinal nerves using a permanently implanted sacral foramen electrode and a battery-powered pulse generator for treatment of different kinds of lower urinary tract dysfunction, refractory to conservative treatment. At our department, chronic unilateral electrical stimulation of the S3 sacral spinal nerve has been used for treatment of vesicourethral dysfunction in 55 patients with a mean postoperative follow-up of 44.3 months. Lasting symptomatic improvement of more than 50% was achieved in 16 of 21 patients with motor urge incontinence (76.2%) and in 22 of the 28 patients with urinary retention (78.6%). In our opinion, chronic sacral neuromodulation offers a sustained therapeutic effect to treatment responders that is not achieved by temporary neuromodulation techniques. Chronic neuromodulation should be considered predominantly in patients with urinary retention and in patients with motor urge incontinence who refuse temporary techniques or who require too much effort to achieve a sustained clinical effect.     

Sacral neuromodulation for refractory detrusor overactivity in women with an artificial urinary sphincter

PURPOSE: We assessed the efficacy of sacral neuromodulation as an alternative therapeutic option in women with an artificial urinary sphincter (AUS) who had de novo irritative urinary symptoms (urgency/frequency) refractory to conventional treatment. MATERIALS AND METHODS: Between 1984 and 2002 we implanted an AUS in 350 women and detrusor overactivity developed in 14. Six of the 14 patients responding positively to a percutaneous nerve evaluation test (greater than 50% subjective/objective improvement) were implanted with an S3 neuromodulator within 42.8 weeks (range 21 to 106) of AUS implantation. Followup included analysis of the voiding diary, a pad test and urodynamic assessment. RESULTS: After 30.5 months followup (range 14 to 40) 1 patient was dry, 4 were improved and treatment failed in 1. At 12 months mean voiding frequency daily had decreased from 17 (range 12 to 23) to 8 (range 4 to 12) and the mean number of leakages episodes daily had decreased from 14.7 (range 8.5 to 17) to 6 (range 4 to 10). Mean voided volume had increased from 121.7 (range 90 to 170) to 180 ml (range 120 to 225), mean first desire to void volume had increased from 117 (range 88 to 190) to 183 ml (range 130 to 275) and mean functional bladder capacity had increased from 325 (range 200 to 530) to 372 ml (range 250 to 580). Uninhibited bladder contractions had resolved in 4 of 5 patients. CONCLUSIONS: In women who already have an AUS with urge incontinence sacral neuromodulation can help resolve symptoms. Because this therapy does not compromise the potential for future treatment, it appears to be an alternative option in these patients. It can postpone or avoid more mutilating surgery and self-catheterization.     

Unilateral versus bilateral sacral neuromodulation in patients with chronic voiding dysfunction

PURPOSE: Bilateral sacral nerve neuromodulation has been proposed as a more effective treatment for chronic voiding dysfunction. However no comparison with the unilateral approach has been performed. We investigated the possible advantage of bilateral sacral neuromodulation. MATERIALS AND METHODS: In a prospective randomized crossover trial we investigated 33 patients who underwent bilateral implantation of a temporary test lead. Unilateral and bilateral test stimulation was continued for 4 to 6 days in all patients. Patients were randomly assigned to start with bilateral or unilateral stimulation. Between the stimulation episodes a 2-day washout interval was scheduled. Voiding diaries were completed at baseline and during the entire stimulation period. Sacral x-rays were taken to confirm lead positioning or possible migration after implantation and at the end of the test stimulation period. After 10 days the temporary leads were removed and voiding diaries were analyzed. RESULTS: After stimulation sacral x-ray revealed test lead migration in 8 patients, leaving 12 patients with urge incontinence and 13 with voiding difficulty and urinary retention available for review. A statistically significant improvement in voiding parameters was seen during the test stimulation period. However no statistically significant improvement was seen due to bilateral stimulation compared to unilateral stimulation. Two patients with urinary retention only started voiding to completion during bilateral stimulation. CONCLUSIONS: Bilateral is in general not superior to unilateral sacral neuromodulation. However, in some individuals bilateral stimulation may be more effective in relieving symptoms. Therefore, if unilateral percutaneous nerve evaluation fails, a bilateral test should be considered.     

Results of sacral neuromodulation therapy for urinary voiding dysfunction: outcomes of a prospective, worldwide clinical study

PURPOSE: This 5-year, prospective, multicenter trial evaluated the long-term safety and efficacy of sacral neuromodulation in patients with refractory urge incontinence, urgency frequency and retention. MATERIALS AND METHODS: A total of 17 centers worldwide enrolled 163 patients (87% female). Following test stimulation 11 patients declined implantation and 152 underwent implantation using InterStim. Of those treated with implantation 96 (63.2%) had urge incontinence, 25 (16.4%) had urgency frequency and 31 (20.4%) had retention. Voiding diaries were collected annually for 5 years. Clinical success was defined as 50% or greater improvement from baseline in primary voiding diary variable(s). RESULTS: Data for all implanted cases were reported. For patients with urge incontinence mean leaking episodes per day decreased from 9.6 +/- 6.0 to 3.9 +/- 4.0 at 5 years. For patients with urgency frequency mean voids per day decreased from 19.3 +/- 7.0 to 14.8 +/- 7.6, and mean volume voided per void increased from 92.3 +/- 52.8 to 165.2 +/- 147.7 ml. For patients with retention the mean volume per catheterization decreased from 379.9 +/- 183.8 to 109.2 +/- 184.3 ml, and the mean number of catheterizations decreased from 5.3 +/- 2.8 to 1.9 +/- 2.8. All changes were statistically significant (p <0.001). No life threatening or irreversible adverse events occurred. In 102 patients 279 device or therapy related adverse events were observed. At 5 years after implantation 68% of patients with urge incontinence, 56% with urgency frequency and 71% with retention had successful outcomes. CONCLUSIONS: This long-term study demonstrates that InterStim therapy is safe and effective for restoring voiding in appropriately selected cases refractory to other forms of treatment.     

Sacral neuromodulation for the symptomatic treatment of refractory interstitial cystitis: a prospective study

PURPOSE: The efficacy of sacral neuromodulation for the treatment of symptoms in patients with refractory interstitial cystitis was evaluated. MATERIALS AND METHODS: A total of 25 patients with a mean age of 47 years and refractory interstitial cystitis were prospectively evaluated with a trial of sacral nerve stimulation. Patients who demonstrated 50% improvement in frequency, nocturia, voided volume and average pain qualified for permanent sacral nerve stimulator implantation. Treatment success was measured by voiding diary, report of average pain, and response to the Interstitial Cystitis Symptom Index and Interstitial Cystitis Problem Index. RESULTS: Of the 25 patients 17 qualified for permanent sacral nerve stimulator implantation. At an average of 14 months followup mean daytime frequency and nocturia improved from 17.1 to 8.7 and 4.5 to 1.1, respectively (p <0.01). Mean voided volume increased from 111 to 264 ml. (p <0.01). Report of average pain decreased from 5.8 to 1.6 points on a scale of 0 to 10 (p <0.01). Interstitial Cystitis Symptom and Problem Index scores decreased from 16.5 to 6.8 and 14.5 to 5.4, respectively (p <0.01). Of the 17 patients 16 (94%) with a permanent stimulator demonstrated sustained improvement in all parameters at the last postoperative visit. CONCLUSIONS: Results of this prospective clinical study demonstrate that sacral neuromodulation is a safe and effective treatment for the dysfunctional voiding and pelvic pain in patients with interstitial cystitis who are refractory to other forms of treatment.     

Detrusor overactivity does not predict outcome of sacral neuromodulation test stimulation

The aim of this study is to determine if urodynamic findings in patients with urge incontinence predicts response to sacral neuromodulation test stimulation. One hundred four patients with refractory urinary urge incontinence who had undergone sacral neuromodulation test stimulation were retrospectively reviewed. Pre- and post-test stimulation incontinence parameters and pelvic floor muscle (PFM) contraction strength was documented. Urodynamics were reviewed on all patients, and the presence or absence of detrusor overactivity (DO) was noted. Patients were then divided into two groups: responders to the test stimulation and non-responders. A positive response was considered to be a ≥50% improvement in the number of incontinent episodes per day (IE/day) and/or pad weight with test stimulation. Of the 104 patients evaluated, 64% (N = 67) responded to the test stimulation, while 36% (N = 37) were non-responders. The mean age was 59.7 and 67.0 among responders and non-responders (p = .01). There was a significant difference in the number of IE/day between non-responders and responders (p = .02). There was no relationship found between the presence or absence of DO and the likelihood for test stimulation success, patient demographics or pre test stimulation incontinence variables. Our study provides no statistically significant evidence that the presence or absence of DO on urodynamics predicts a response to sacral neuromodulation test stimulation. An important finding, however, was that patients without demonstrable DO on urodynamics may still have a positive response to sacral neuromodulation.     

Electrical neuromodulatory therapy in female voiding dysfunction

Female voiding dysfunction such as urge-frequency syndrome, urge incontinence and unobstructive urinary retention are often refractory to conservative management. Electrical neuromodulation with surface electrodes or with implantable systems has become a valuable addition to the therapeutic options in the last two decades. Interstitial cystitis is an emerging indication. The application of these techniques in non-neurogenic patients is reviewed. The techniques using unimplantable electrodes, anogenital electrical stimulation with plug electrodes, transcutaneous electrical nerve stimulation with surface electrodes, and posterior tibial nerve stimulation using needle electrodes are addressed. Several techniques using implantable systems are discussed, e.g. sacral nerve neuromodulation (Interstim device), pudendal nerve stimulation (Interstim and Bion device) and paraurethral neuromodulation (Miniaturo device). The long-term efficacy of neuromodulation for the established indications is more than half, but 20-50% of the patients initially tested do not respond to a test procedure. The disadvantage is the high surgical revision rate and the high cost of treatment. Technical advances will hopefully be able to address these aspects.     

Implantable neuromodulation for urinary urge incontinence and fecal incontinence: a urogynecology perspective

Implantable sacral nerve stimulation is a minimally invasive, durable, and reversible procedure for patients with urinary urge and fecal incontinence who are refractory to conservative therapy. The therapy is safe compared with other surgical options. An intact external or internal rectal sphincter is not a prerequisite for success in patients with fecal incontinence.     

Sacral neuromodulation in the treatment of the unstable bladder

Sacral neuromodulation as a treatment for urge incontinence in patients with an unstable bladder is the subject of ongoing clinical studies. Although approximately 75% of the patients treated with a permanent sacral foramen electrode implant have experienced significant improvements, it is now also clear that there is an initial failure rate of about 25%. Recent studies have pointed out the importance of improved patient selection on the basis of sex differences, urodynamic parameters and psychological factors. Also, newer forms of test stimulation and permanent electrode implantation are being explored in an effort to improve on the present results.     

Early versus late treatment of voiding dysfunction with pelvic neuromodulation

Introduction:

Pelvic neuromodulation is an established method of treating voiding dysfunction. Little is known about the pathophysiology associated with voiding dysfunction. Reports have suggested that a delay in treating patients with sacral neuromodulation therapy can impact the success rate of this type of treatment in voiding dysfunction. We examined patient response to pelvic neuromodulation when it was applied early versus late in the postdiagnosis of voiding dysfunction.

Methods:

We conducted a retrospective study of 42 patients (38 women and 4 men) with voiding dysfunction who underwent surgery for implant with the Interstim (Medtronic, Minneapolis, Minn.). Prior to implantation, patients were required to pass a percutaneous nerve evaluation (PNE) over a 1-week period. Patients were observed for 20–48 months postimplantation. All patients recorded their voiding parameters at baseline, after screening and every 6 months thereafter. Twenty patients (in the early group) underwent implant surgery with the neurostimulator 2–4 weeks post-PNE, and 22 patients (the late group) had the device implanted 6–24 months post-PNE owing to local logistical circumstances.

Results:

In the early group, 16 of 20 patients (80%) maintained a good response. In the late group, 13 of 22 (59%) patients showed a good response. Groups were well matched in terms of age, duration of voiding dysfunction and incidence of comorbidity.

Conclusion:

Patients who were delayed more than 6 months in receiving the neurostimulator implant showed a worse response than did patients who had the device implanted soon after PNE. This indicates the possibility of disease progression, which may limit the response to sacral neuromodulation.Sacral neuromodulation (SNM), using permanent foramen S3 electrode, offers an alternative treatment for patients with conditions refractory to conventional measures. SNM has been approved by the US Food and Drug Administration for 3 indications: urge incontinence (UI), urge frequency (UF) and nonobstructive urinary retention. Several reports have been published regarding the efficacy of SNM in the treatment of UI, UF and nonobstructive urinary retention.^1–4SNM is considered a minimally invasive procedure, and when compared with the more drastic procedures to control intractable overactive bladder symptoms, SNM has fewer complications and has provided patients with more durable and consistent bladder control over time.The purpose of the current study is to determine whether a delay in SNM can affect the long-term outcome of treatment in patients with voiding dysfunction.     

骶神经刺激治疗膀胱排尿功能障碍

目的：观察骶神经刺激治疗膀胱排尿功能障碍的疗效。方法：采用经皮穿刺刺激骶3神经治疗4例排尿功能障碍患者,其中1例接受永久性神经刺激器植入治疗。通过排尿日记及患者症状评价疗效。结果：3例难治性尿频尿急综合征的患者症状有显著改善,且排尿次数显著减少,平均排尿量增加,尿急程度减轻;另1例膀胱收缩无力患者无效。结论：骶神经刺激可以显著地改善部分患者膀胱排尿功能障碍。     

Successful use of sacral neuromodulation after failed bladder augmentation

Sacral neuromodulation has become a standard minimally invasive therapy for refractory urinary urge/frequency and urge incontinence. Prior to the widespread use of sacral neuromodulation, augmentation cystoplasty was a standard treatment for refractory overactive bladder (OAB). The use of sacral neuromodulation following bladder augmentation has not been previously reported in the literature. We report 2 cases of successful sacral neuromodulation in patients with OAB refractory to bladder augmentation.     

Chronische sakrale bilaterale Neuromodulation Einsatz einer minimalinvasiven Implantationstechnik bei Patienten mit Blasenfunktionsstörungen

The implantable neuromodulation system described by Tanagho and Schmidt enables unilateral sacral nerve stimulation. Reports have been made on sacral neuromodulation failures of up to 50% in patients undergoing this procedure. We chose the bilateral electrode implantation and a minimal invasive laminectomy to ensure a more effective modulation and better placement and fixation of the electrodes. After successful assessment using a peripheral nerve evaluation test, 20 patients (14 with detrusor instability, 6 with hypocontractile detrusor) underwent minimally invasive laminectomy and bilateral electrode placement. In the patients with detrusor instability, the incontinence episodes were reduced from 7.2 to 1 per day and the bladder capacity improved from 198 to 352 ml. In patients with hypocontractile detrusor, the initial residual urine level of 450 ml dropped to 108 ml. Maximum detrusor pressure during micturition rose from 12 cmH2O initially to 34 cmH2O. The average follow up period was 17.5 months. There was no sign of deterioration in the modulation effect in any of the patients. Bilateral electrode implantation and the new sacral approach allow optimal neuromodulation in patients with bladder dysfunction. Laminectomy enables optimum electrode placement and fixation with minimal trauma.     

Alternative approaches to sacral nerve stimulation

Bladder dysfunction is a very prevalent disorder and often refractory to behavioral and pharmacologic therapies. Sacral nerve stimulation is an approved method of managing urinary urgency, frequency, urge incontinence, and urinary retention. Alternative approaches to neuromodulation are being developed. The purpose of this paper is to describe emerging approaches to neuromodulation for voiding dysfunction. A current review of alternative methods of neuromodulation is discussed. This includes stimulation of the tibial nerve via a percutaneous approach, methods of stimulating the pudendal nerve to obtain afferent stimulation through sacral roots S2–S4, chemo-neuromodulation using botulinum toxin, and anogenital stimulation. These various methods are described and the current literature reviewed. Neuromodulation is an alternative to traditional management of voiding dysfunction. A benefit of neuromodulation is that it is minimally invasive and reversible. New sites of stimulation are being developed to add to our treatment options.