Biomedical subjects

P E van Kerrebroeck

Publications and source records attributed to P E van Kerrebroeck.

At least 19 recordsLinked to original sources

PubMed2001

[Neuromodulation and neurostimulation in urology].

Functional voiding disorders, such as urge incontinence and urine retention, have a high prevalence and often lead to stigmatisation and a diminished quality of life. Patients with idiopathic voiding dysfunctions, for whom conservative treatments are insufficient, can currently be treated with sacral neuromodulation. In sacral neuromodulation a pulse generator is implanted; it is a reversible treatment that can be tested beforehand to evaluate if the patient is eligible for it. After implantation a good result is obtained, on average, in 73% of patients. Patients with spinal cord injury may currently be treated with electrical neurostimulation of the anterior sacral roots, which results in the ability to void without a residue, evacuate stools and obtain an erection or vaginal lubrication. Over 80% of the implanted patients with a spinal cord injury void without residual urine. Furthermore, continence is restored and the bladder capacity increases. In patients with therapy-resistant functional micturition disorders and in patients with spinal cord injury, neuromodulation and neurostimulation must be considered before invasive surgery is carried out.

Electric Stimulation Therapy↗

PubMed2001

Efficacy of sacral nerve stimulation for urinary retention: results 18 months after implantation.

PURPOSE: We investigate the efficacy of sacral neurostimulation in patients with idiopathic urinary retention in a prospective, randomized multicenter trial. MATERIALS AND METHODS: A total of 177 patients with urinary retention refractory to standard therapy were enrolled in the study. Greater than 50% improvement in baseline voiding symptoms during a 3 to 7-day percutaneous test stimulation qualified a patient for surgical implantation of an InterStim parallel system. Of the patients who qualified for implantation 37 were randomly assigned to a treatment and 31 to a control group. Patients in the treatment group underwent early surgical implantation of the sacral nerve stimulation system, while implantation was delayed in the control group for 6 months. Followup evaluations, including voiding diary analysis and temporary deactivation of the stimulator at 6 months, were conducted at 1, 3, 6, 12 and 18 months after implantation in the treatment group, and after 3 and 6 months in the control group. RESULTS: Compared to the control group, patients implanted with the InterStim system had statistically and clinically significant reductions in the catheter volume per catheterization (p <0.0001). Of the patients treated with implants 69% eliminated catheterization at 6 months and an additional 14% had a 50% or greater reduction in catheter volume per catheterization. Therefore, successful results were achieved in 83% of the implant group with retention compared to 9% of the control group at 6 months. Temporary inactivation of sacral nerve stimulation therapy resulted in a significant increase in residual volumes (p <0.0001) but effectiveness of sacral nerve stimulation was sustained through 18 months after implant. CONCLUSIONS: Results of this prospective, randomized clinical study demonstrate that sacral nerve stimulation is effective for restoring voiding in patients with retention who are refractory to other forms of treatment.

Adult↗

PubMed2001

Buttock placement of the implantable pulse generator: a new implantation technique for sacral neuromodulation--a multicenter study.

OBJECTIVE: In the standard operation procedure for sacral neuromodulation, the implantable pulse generator (IPG) is implanted in a subcutaneous pocket at the lower part of the anterior abdominal wall. This procedure requires a long operation time and three incisions. With the IPG in the abdominal wall, some patients complain of displacement or pain at the IPG site postoperatively. By modifying the technique of placement of the IPG, these disadvantages are overcome. METHODS: Between August 1999 and July 2000, 39 patients underwent a buttock implant of the IPG. In 2 of these patients the position of the IPG was changed from abdominal region to the buttock. During follow-up, complications concerning the operation and location of the IPG were compared to the published literature. RESULTS: Operation time is reduced in all patients by approximately 1 h. No repositioning of the patient is required during surgery. Only a short subcutaneous tunnel is required to connect the lead to the IPG. Pain at the level of the IPG was noted in 10% of the patients, which needed no further treatment. No infections were seen and the IPG did not displace postoperatively. CONCLUSION: Buttock placement of the IPG in sacral nerve stimulation leads to shorter operation time; only two incisions are needed instead of three and a shorter subcutaneous tunnel is needed. Using this technique there are less complications and a lower re-operation rate.

Adult↗

PubMed2001

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.

Adult↗

PubMed2000

Long-term results of a multicenter study on sacral nerve stimulation for treatment of urinary urge incontinence, urgency-frequency, and retention.

Many patients have chronic, debilitating symptoms of voiding dysfunction that are refractory to conventional medical or surgical therapies. This multicenter, prospective study evaluated the long-term effectiveness of sacral nerve stimulation using the implantable Medtronic InterStim therapy for urinary control in patients with otherwise intractable complaints of urinary urge incontinence, urgency-frequency, or retention. Each patient first underwent temporary, percutaneous sacral nerve test stimulation. If at least a 50% reduction in target symptoms was documented for at least 3 days, patients received a permanent Medtronic InterStim sacral nerve stimulation system that includes a surgically implanted lead and neurostimulator. Regular follow-up was conducted with outcome data. We report here on patients who have been observed from 1.5 to 3 years postimplantation. The results demonstrate that after 3 years, 59% of 41 urinary urge incontinent patients showed greater than 50% reduction in leaking episodes per day with 46% of patients being completely dry. After 2 years, 56% of the urgency-frequency patients showed greater than 50% reduction in voids per day. After 1. 5 years, 70% of 42 retention patients showed greater than 50% reduction in catheter volume per catheterization. We conclude that the Medtronic InterStim therapy for urinary control system is an effective therapy with sustained clinical benefit for patients with intractable symptoms of urinary urge incontinence, urgency-frequency, or retention.

Adolescent↗

PubMed2000

Conservative treatment of urge urinary incontinence in women: a systematic review of randomized clinical trials.

OBJECTIVE: To assess the efficacy of physical therapies for first-line use in the treatment of urge urinary incontinence (UUI) in women, using a systematic review of randomized clinical trials (RCTs). MATERIALS AND METHODS: A computer-aided and manual search was carried out for RCTs published between 1980 and 1999 investigating the treatment of UUI defined by the keywords 'physical therapies', e.g. bladder (re)training (including 'behavioural' treatment), pelvic floor muscle (PFM) exercises, with or without biofeedback and/or electrical stimulation. The methodological quality of the included trials was assessed using methodological criteria, based on generally accepted principles of interventional research. RESULTS: Fifteen RCTs were identified; the methodological quality of the studies was moderate, with a median (range) score of 6 (3-8.5) (maximum possible 10). Eight RCTs were considered of sufficient quality, i.e. an internal validity score of >/= 5.5 points on a scale of 0-10, and were included in a further analysis. Based on levels-of-evidence criteria, there is weak evidence to suggest that bladder (re)training is more effective than no treatment (controls), and that bladder (re)training is better than drug therapy. Stimulation types and parameters in the studies of electrical stimulation were heterogeneous. There is insufficient evidence that electrical stimulation is more effective than sham electrical simulation. To date there are too few studies to evaluate effects of PFM exercise with or without biofeedback, and of toilet training for women with UUI. CONCLUSION: Although almost all studies included reported positive results in favour of physical therapies for the treatment of UUI, more research of high methodological quality is required to evaluate the effects of each method in the range of physical therapies.

Behavior Therapy↗

PubMed2000

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.

Adult↗

PubMed2000

Sacral neuromodulation in the treatment of urgency-frequency symptoms: a multicenter study on efficacy and safety.

PURPOSE: Neuromodulation of sacral nerves has shown promising results in correcting voiding dysfunction. We report the results of a multicenter trial designed to assess the efficacy of sacral nerve neuromodulation in patients presenting with refractory urinary urgency-frequency. MATERIALS AND METHODS: A total of 51 patients from 12 centers underwent baseline assessment, including a detailed voiding diary, urodynamic evaluation and percutaneous test stimulation of the sacral nerves at S3 and/or S4. All patients enrolled in the study had undergone prior conventional treatment, such as pharmacotherapy, hydrodistention and surgical intervention, which failed. All patients demonstrated a satisfactory response to trial stimulation and were randomly divided into a stimulation group (25 patients) and a control group (26). A sacral nerve stimulation device was implanted after 6 months in the control group. Patients were followed at 1, 3 and 6 months, and at 6-month intervals for up to 2 years after implantation of a neuroprosthetic InterStim* system. dagger The study variables included the number of voids daily, volume voided per void and degree of urgency before void. RESULTS: Compared to the control group, 6-month voiding diary results demonstrated statistically significant improvements (p <0.0001) in the stimulation group with respect to the number voids daily (16.9 +/- 9.7 to 9.3 +/- 5.1), volume per void (118 +/- 74 to 226 +/- 124 ml.) and degree of urgency (rank 2.2 +/- 0.6 to 1.6 +/- 0.9). Patients in the control group showed no significant changes in voiding parameters at 6 months. Significant improvements in favor of the stimulation group were noted in various parameters with respect to water cystometry and quality of life (SF-36). At 6 months after implant, neurostimulators were turned off in the stimulation group and urinary symptoms returned to baseline values. After reactivation of stimulation sustained efficacy was documented at 12 and 24 months. CONCLUSIONS: Neuromodulation of the sacral nerves is an effective, safe therapy that successfully treats significant symptoms of refractory urgency-frequency.

Adult↗

PubMed2000

Novel test lead designs for sacral nerve stimulation: improved passive fixation in an animal model.

PURPOSE: To evaluate the ability of two novel coiled test stimulation lead designs to reduce or eliminate undesired migration and concomitant loss or attenuation of responsiveness to sacral nerve stimulation (SNS) associated with standard percutaneous nerve evaluation (PNE) leads. MATERIALS AND METHODS: The two novel leads (Coiled Leads 1 and 2) and a standard PNE lead were inserted bilaterally in sacral foramina of female goats. At various times thereafter threshold voltage responses were measured. Prior to lead removal, distance of lead migration was evaluated by x-ray imaging and the force necessary to displace the leads measured. Thereafter, as the leads were being removed, the force necessary for removal was also measured. RESULTS: Migration was consistently either nil or minimal for both coiled leads. In contrast, migration of the standard lead occurred in all cases and was substantial in magnitude. A significant linear association was evident between the migration distance of the standard lead and the corresponding voltages needed to evoke a response. The forces necessary to displace Coiled Lead 1 and Coiled Lead 2 were both significantly higher (p <0.01) than those for the standard lead. In some cases comparatively high forces were needed for removal of Coiled Lead 1 but not Coiled Lead 2. CONCLUSIONS: Coiled lead designs appear to offer a potentially promising alternative to standard leads for PNE, allowing a wider range of patients to be correctly identified as candidates for sacral root neuromodulation. Coiled Lead 2 merits further investigation in human subjects.

Animals↗

PubMed1999

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.

Adult↗

PubMed1998

Selective detrusor activation by sacral ventral nerve-root stimulation: results of intraoperative testing in humans during implantation of a Finetech-Brindley system.

Electrical sacral nerve-root stimulation can be used to induce bladder contraction. However, bladder emptying is hampered by simultaneous contraction of the external urethral sphincter. Voiding may improve when using a stimulation method that allows selective detrusor activation. Both theoretical and animal studies have demonstrated that it is possible to obtain selective detrusor activation by sacral root stimulation using an selective anodal block. The objective of this paper is to demonstrate the feasibility of this stimulation method in humans. For investigation of the stimulation method, intraurethral and intravesical pressure responses to sacral root stimulation were measured in acute experiments on 12 patients. The results show that selective detrusor activation is possible in patients. Future perspectives are discussed.

Electric Stimulation↗

PubMed1997

Urinary bladder control by electrical stimulation: review of electrical stimulation techniques in spinal cord injury.

Evacuation of urine in paraplegics without the need for catheters would be possible when voiding could be induced by eliciting a bladder contraction. A challenging option to obtain detrusor contraction is electrical stimulation of the detrusor muscle or its motor nerves. This article reviews the 4 possible stimulation sites where stimulation would result in a detrusor contraction: the bladder wall, the pelvic nerves, the sacral roots, and the spinal cord. With respect to electrode application, sacral root stimulation is most attractive. However, in general, sacral root stimulation results in simultaneous activation of both the detrusor muscle and the urethral sphincter, leading to little or no voiding. Several methods are available to overcome the stimulation-induced detrusor-sphincter dyssynergia and allow urine evacuation. These methods, including poststimulus voiding, fatiguing of the sphincter, blocking pudendal nerve transmission, and selective stimulation techniques that allow selective detrusor activation by sacral root stimulation, are reviewed in this paper.

Electric Stimulation↗

PubMed1997

Selective detrusor activation by electrical stimulation of the human sacral nerve roots.

The purpose of this study was to investigate the feasibility of selective detrusor activation without activation of the urethral sphincter by sacral root stimulation in patients. The sacral roots were stimulated using a tripolar electrode. An anodal block was used to prevent the urethral sphincter from contraction. Using square current pulses (700 microseconds, 6-7 mA), no increase in intraurethral pressure was measured, while a normal increase in intravesical pressure occurred. The minimum pulse duration to obtain a complete block was 550 microseconds. The study shows that anodal blocking of action potentials is possible in humans and can result in selective detrusor activation when used in sacral root stimulation.

Action Potentials↗

PubMed1997

Sacral rhizotomies and electrical bladder stimulation in spinal cord injury. 2. Cost-effectiveness and quality of life analysis. Dutch Study Group on Sacral Anterior Root Stimulation.

OBJECTIVES: To present a cost-effectiveness analysis of sacral rhizotomies and electrical bladder stimulation compared with conventional care of neurogenic bladder dysfunction in patients with spinal cord injury. METHODS: During a 3-year inclusion period, data on costs and quality of life before the intervention were collected to describe conventional care. Data on the pre-implantation period, the implantation and a follow-up period of 2 years were collected following a strict protocol simultaneous with medical and urodynamic data and were used to calculate the costs and effects on quality of life of the implantation of the stimulator. RESULTS: Between June 1991 and June 1994, 52 patients with complete cervical or thoracic spinal cord lesions underwent sacral posterior rhizotomies and implantation of a Finetech-Brindley sacral anterior root stimulator. Although the initial costs of sacral anterior root stimulation are high, they are earned back in this series in about 8 years after the implantation. General indicators of the quality of life show no significant changes after the implantation. Factors related to psychological well-being and the patients' satisfaction with the emptying of the bladder increased significantly whereas the experienced problems of micturition and incontinence all decreased significantly. CONCLUSION: Sacral rhizotomies and electrical bladder stimulation make a cost-effective method of treatment of lower urinary tract dysfunction in patients with spinal cord injury. Considerable savings on health care costs are possible in the long run with simultaneous positive effects on aspects of health status.

Adolescent↗

PubMed1997

Selective detrusor activation by electrical sacral nerve root stimulation in spinal cord injury.

Electrical sacral nerve root stimulation can be used in spinal cord injury patients to induce urinary bladder contraction. However, existing stimulation methods activate simultaneously both the detrusor muscle and the urethral sphincter. Urine evacuation is therefore only possible using poststimulus voiding. Micturition would improve if the detrusor muscle could selectively be activated. The purpose of this study was to demonstrate selective detrusor activation in patients by ventral sacral root stimulation. The stimulation method involves selective activation of the small diameter myelinated nerve fibers and consists of a combination of cathodal excitation and selective anodal blocking using a tripolar electrode. To investigate anodal blocking, the intraurethral pressure response to stimulation was measured in acute experiments performed on 12 patients. The influence of both pulse amplitude and pulse duration on the pressure response was analyzed. In 8 out of 12 patients anodal blocking of somatic motor fibers was possible. This study also indicates the feasibility of selective detrusor activation by sacral root stimulation.

Electric Stimulation Therapy↗

PubMed1995

Relationship between lower urinary tract abnormalities and disease-related parameters in multiple sclerosis.

Multiple sclerosis affects the lower urinary tract in many patients. The relationship between lower urinary tract abnormalities and disease-related parameters of multiple sclerosis is not well described. We screened urologically and neurologically 212 patients according to a standard protocol. Micturition complaints were noted in 52% of the patients and urodynamic abnormalities were found in 64%. A statistical correlation was found between detrusor hyperactivity and detrusor hypoactivity with disease-related parameters, that is disease duration, disability status, myelin basic protein concentration in the cerebrospinal fluid and neurophysiological investigations. No relationship was found between detrusor hypersensibility or detrusor hyposensibility and the aforementioned disease-related parameters. In 1 patient upper urinary tract abnormalities were noted in combination with urodynamic abnormalities. We conclude that lower urinary tract abnormalities can be found in every patient with multiple sclerosis unrelated to the state of the disease. Severe upper urinary tract abnormalities are rare.

Adolescent↗

PubMed1994

Predictors of success with neuromodulation in lower urinary tract dysfunction: results of trial stimulation in 100 patients.

Chronic lower urinary tract dysfunction can be treated by sacral neuro-stimulation. Clinical parameters for selection of patients for this expensive and invasive treatment modality are not well defined to date. Therefore, before implantation of a permanent stimulator, the effect is tested by temporary implantation of a wire electrode connected to an external stimulator. According to the literature, many patients do not respond during temporary implantation and a mean of 25% of the patients with a permanent stimulator implanted fail to respond as well. To improve patient selection, we attempted to define clinical parameters to predict the outcome of sacral neuro-stimulation in 100 consecutive patients who were tested with temporary sacral stimulation. A total of 34 patients achieved a complete cure on trial stimulation. It appeared that detrusor overactivity and urethral instability responded best but they were not predictors of success. We conclude that neither gender, patient age, history nor diagnosis are predictors of success in sacral neuro-stimulation of lower urinary tract dysfunction.

Adolescent↗

PubMed1994

Selective stimulation of sacral nerve roots for bladder control: a study by computer modeling.

The aim of this study was to investigate theoretically the conditions for the activation of the detrusor muscle without activation of the urethral sphincter and afferent fibers, when stimulating the related sacral roots. Therefore, the sensitivity of excitation and blocking thresholds of nerve fibers within a sacral root to geometric and electrical parameters in tripolar stimulation using a cuff electrode, have been stimulated by a computer model. A 3-D rotationally symmetrical model, representing the geometry and electrical conductivity of a nerve root surrounded by cerebrospinal fluid and a cuff was used, in combination with a model representing the electrical properties of a myelinated nerve fiber. The electric behavior of nerve fibers having different diameters and positions in a sacral root was analyzed and the optimal geometric and electrical parameters to be used for sacral root stimulation were determined. The model predicts that an asymmetrical tripolar cuff can generate unidirectional action potentials in small nerve fibers while blocking the large fibers bidirectionally. This result shows that selective activation of the detrusor may be possible without activation of the urethral sphincter and the afferent fibers.

Animals↗