Fecal incontinence improved, with and without treatment
Leroi AM, Parc Y, Lehur PA, et al. Efficacy of sacral nerve stimulation for fecal incontinence. Results of a multicenter double-blind crossover study. Ann Surg. 2005;242:662–669.
In this randomized crossover trial, 24 patients with fecal incontinence at least once a week for 3 months received InterStim. Patients were randomized to have the device ON or OFF for 1 month, and in the opposite mode (OFF or ON) for the 2nd month. At the end of the study, patients were given the option of keeping the SNS ON or OFF. Patients and outcome assessors were blinded to treatment assignment. All patients completed the study.
Primary outcomes were number of weekly incontinence and urgency episodes and mean delay for postponing defecation measured with patient diaries; quality of life as measured by the Cleveland Clinic score; and manometric data.
The median frequency of fecal incontinence episodes was significantly decreased in the ON mode compared with the OFF mode. There was improvement in quality of life scores as well. There was no significant change in the frequency of urgency episodes, the delay in postponing defecation, or number of bowel movements per week. There was an increase in maximum anal resting pressure in the ON mode. There were no differences in any other manometric parameters between the 2 modes.
Although symptoms improved markedly during the ON crossover mode, there was also significant improvement in the OFF mode compared with baseline. The median frequency of fecal incontinence episodes decreased by 90% in the ON mode, but also decreased by 76% in the OFF mode. Also, 89% of patients reported improvement during the ON mode and 63% reported improvement during the OFF mode.
It is unclear if subjects were aware of which mode setting they were randomized to, or if there was significant placebo effect.
ADDITIONAL REFERENCES
- Rasmussen OO, Buntzen S, Sorensen M, Laurberg S, Christiansen J. Sacral nerve stimulation in fecal incontinence. Dis Colon Rectum. 2004;47:1158–1163.
Does the pudendal mini-stimulator improve detrusor overactivity?
Groen J, Amiel C, Rudd Bosch JLH. 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. Neurourol Urodynam. 2005;24:226–230.
The effectiveness of sacral neuromodulation has sparked innovations for other forms of neuromodulation besides the InterStim system. Utilizing the effects of stimulation on the pudendal afferents and in hopes of achieving similar results without central sacral stimulation, another type of neuromodulation has been developed: direct stimulation of the pudendal nerve by the Bion Device (Advanced Bionics Corp., Valencia, Calif). It is a self-contained, battery-powered mini-neurostimulator with integrated electrodes. It measures 28 x 3.3 mm and weighs 0.7 grams.
It is implanted in a minimally invasive fashion adjacent to the pudendal nerve at Alcock’s canal.
Other treatments had failed. This pilot study by Groen and colleagues evaluated short-term results of 6 women with refractory detrusor overactivity, in whom conservative and medical therapy and various forms of neuromodulation were unsuccessful, and who had positive percutaneous pudendal nerve screening tests.
Voiding–incontinence diaries, cystometrics, and the SF-36 quality-of-life health survey were measured. Women were followed for 6 months with the device ON, and for an additional 2 weeks with the device OFF.
Higher bladder volume remained better or returned to baseline
At the end of the 6-month ON period, the number of incontinence episodes per day, number of pads used per day, and leakage severity index decreased significantly compared with baseline (P<.05 for all). Cystometric comparisons revealed a higher bladder volume at the first involuntary detrusor contraction (P<.05). These values returned toward baseline when the device was turned OFF, although in most cases, still remained better than baseline.
There were no statistically significant changes in the 8 domains of the SF-36 survey, likely due to the small number of patients.
ADDITIONAL REFERENCES
- Bosch JLHR. The Bion Device: a minimally invasive implantable ministimulator for pudendal nerve neuromodulation in patients with detrusor overactivity incontinence. Urol Clin N Am. 2005;32:109–112.
- Daneshgari F. Applications of neuromodulation of the lower urinary tract in female urology. Int Braz J Urol. 2006;32:262–272.
- Spinelli M, Malaguti S, Giardiello G, et al. A new minimally invasive procedure for pudendal nerve stimulation to treat neurogenic bladder: description of the method and preliminary data. Neurourol Urodynam. 2005;24:305–309.