Hypothesis / aims of study
Sacral neuromodulation (SNM) has been successfully tried in the treatment of bladder pain conditions (1). However, we have not been able to find any reports of the effect of SNM in patients with painful postmicturion or after contractions, after contraction defined as the ”pressure increase after flow ceases at the end of micturition” (2). We here present a case series of such patients.
Study design, materials and methods
7 patients, all female, age 20-27 years with a long history of daily bladder pain immediately after completed micturition were referred to our pelvic care center. The patients were all in good health and none had neurological disorders. They had all tried mirabegron 50 mg and 6 had also used anticholinergics with no effect of the drug treatment on symptoms in 5 and moderate effect in 2 of the patients. In 4 of the patients the pain was so severe that they had quit work or delayed studies, the remaining 3 reported very bothersome symptoms with life quality impairment. Standard urodynamics with pressure flow demonstrated filling phase overactivity in 3 patients. All 7 had painful after contractions, the pain at the after contraction during the pressure-flow study mimicking the pain they regularly experienced after micturition. There were no other signs of bladder dysfunction. The 7 patients had a tined lead implanted in a first session. They then had a test period of approximately 3 weeks with a temporary pacemaker before implantation of the InterStim. The patients have had our standard follow-up regime for SNM patients to evaluate response and functioning of the InterStim at 6 weeks, 3,6 and 9 months and then yearly. We have performed a new urodynamic examination in 4 of the patients with the InterStim in place and turned on.
Interpretation of results
This is a small cohort of patients with an unusual type of bladder pain. The results were consistent, all the patients implanted responded to the treatment and had a strong symptom relief that has persisted in most of the patients. SNM appears to change the perception of the pain elicited by the after contraction as the contraction is still present during treatment. The observation period is relatively short, but the observed efficacy is similar to results when SNM is used for other indications. At present we have only had female patients, no males. We have no explanation for this gender difference.