Biomedical subjects

W A Scheepens

Publications and source records attributed to W A Scheepens.

7 recordsLinked to original sources

PubMed2005

European experience with bilateral sacral neuromodulation in patients with chronic lower urinary tract dysfunction.

Although there is experimental and clinical evidence that bilateral stimulation of the sacral nerves could lead to summation effects, no significant differences in unilateral versus bilateral neuromodulation could be demonstrated in a comparative trial. In some individuals, however, only bilateral stimulation relieved symptoms. Therefore, if a unilateral percutaneous nerve evaluation test fails, a bilateral test should be considered. Further clinical research with long-term follow-up will allow the identification of which patients could benefit from bilateral stimulation with greater specificity and ameliorate further the long-term results achieved with unilateral SNS.

Electric Stimulation Therapy↗

PubMed2003

Urodynamic results of sacral neuromodulation correlate with subjective improvement in patients with an overactive bladder.

OBJECTIVES: Standard urodynamic investigations showed no correlation between the efficacy of sacral neuromodulation (SNS) and urodynamic data. Ambulant urodynamic investigations (ACM) are presented as more sensitive and reliable in detecting and quantifying bladder overactivity. In this study we looked at the correlation and results of ambulant urodynamic data and the clinical effects of SNS. METHODS: Data of patients with bladder overactivity, who underwent an ACM before and during SNS were investigated. Blind analyses of the ACM were performed and the detrusor activity index (DAI) was calculated as the degree of bladder overactivity of the detrusor. The ACM parameters, before and during SNS, were analyzed and correlated to the clinical effect of SNS. RESULTS: In 22 of the 34 patients a DAI before and during stimulation could be calculated because of quality aspects. In all other patients, the other ambulatory urodynamic parameters could be analyzed and a significant reduction was found in bladder overactivity. A significant correlation (p = 0.03) was found in DAI reduction of the ACM before and during SNS as compared to the clinical improvement in overactive bladder symptoms. CONCLUSIONS: The objective and subjective results show a decrease in bladder overactivity during SNS. During SNS bladder instabilities are still present, which is in accordance with the published literature. The reduction of the DAI during SNS as compared to before SNS correlates significantly to the clinical effect of SNS.

Adult↗

PubMed2002

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.

Adult↗

PubMed2002

Predictive factors for sacral neuromodulation in chronic lower urinary tract dysfunction.

OBJECTIVES: To investigate data from 211 patients who underwent a trial stimulation (percutaneous nerve evaluation [PNE]) to determine the clinical parameters that can enhance the prediction of PNE success. The advantageous effect of sacral neuromodulation depends on the accurate identification of suitable candidates during the preimplantation PNE. METHODS: A total of 211 patients (161 women and 50 men), with refractory urge incontinence, urgency-frequency syndrome, and urinary retention, underwent a PNE. Patient data (demographics, medical history, urologic investigations, and diagnosis) were collected. The PNE results were evaluated from a voiding diary and patient history. More than 50% improvement of voiding parameters was considered a successful PNE, and those patients were selected for implantation. Logistic regression analysis was performed. The factors tested for predicting the test result were sex, patient age, diagnosis, previous surgery, neurogenic bladder dysfunction, duration of complaints, and previous treatments. RESULTS: The PNEs were positive in 85 patients (40.3%) and negative in 105 patients (49.8%). In 18 patients (8.5%), the test electrode had migrated; 3 more patients were not assessable and were also excluded. Missing data on the variable "duration of complaints" reduced the number of patients in the analyses from 190 to 174 patients. CONCLUSIONS: Intervertebral disk prolapse, duration of complaints, neurogenic bladder dysfunction, and urge incontinence were found to be significant predictive factors. However, a PNE remains necessary to evaluate a patient's chance of implant success objectively.

Adult↗

PubMed2002

Long-term efficacy and safety results of the two-stage implantation technique in sacral neuromodulation.

OBJECTIVE: To assess the long-term efficacy and safety of two-stage sacral neuromodulation with an implantable pulse generator (IPG) in patients treated for urinary urge incontinence (UI) and/or urinary retention (UR). PATIENTS AND METHODS: The two-stage technique is used if patients have a good response during the acute phase of the percutaneous nerve evaluation (PNE) test, but have a poor response during the following 4-7 days (subchronic phase). In the first stage only the permanent electrode was implanted and connected to a temporary external stimulator, allowing patients to be assessed for longer. If the main symptoms improved by more than half the patient proceeded to the second stage, the insertion of the IPG. We reviewed all patients who underwent two-stage implantation; all had signed an informed consent and were asked to complete voiding diaries and a questionnaire to assess the subjective effects of the therapy. Safety was assessed from relevant medical events, management, and relative to the thera-py and resolution. Residual urine was assessed by self-catheterization. The long-term voiding diary results were compared with baseline estimates and analysed statistically using the two-sided Student's t-test. RESULTS: Between 1991 and 1998, 15 patients (13 women and two men, mean age 53 years, range 44-66) underwent the two-stage technique; the mean (median, range) follow-up was 4.9 (5.2, 2.5-7.5) years. Seven patients had UI and seven had UR, with one having both. The mean (range) number of PNEs undertaken in each patient was 2.1 (1-4) and these all failed in the subchronic phase. All patients underwent a first- and second-stage implant after a mean (range) screening period of 12.2 (2-29) days. One patient was explanted after implantation of only the first stage, and two others explanted in a later phase because the IPG was ineffective during the follow-up. The voiding diary results of the remaining 12 patients showed improvement in all the main variables, and in the subjective assessment 11 reported an improvement and were satisfied with the therapy. There were 17 adverse events, 14 of which were resolved and seven of which required surgical intervention. CONCLUSION: The long-term results of the two-stage implantation show clinically and statistically significant improvements, probably because the implantation of the lead (first stage) more closely resembles the final therapy. If a temporary PNE test is not optimal (lead migration, longer testing needed), the two-stage technique can offer a good and safe alternative of comparable efficacy in the long-term. If the two-stage technique had not been available to these 12 patients they would not have been offered neuromodulation.

Adult↗

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

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↗