ABSTRACT
BACKGROUND: Biofeedback has been recommended for the treatment of anorectal disorders, especially constipation and fecal incontinence (FI). The objective of this study was to assess the long-term efficacy of biofeedback and evaluate baseline electromyography (EMG) as a predictor for maintenance of long-term improvement. METHODS: A retrospective chart review was performed on randomly selected patients who underwent biofeedback between the years 1990 and 2000. Clinical characteristics, including EMG values at baseline (resting and contraction) as well as EMG after exercises, were collected. Patients were contacted and were classified as "improved" if they had self-reported symptomatic improvement and "not-improved" if their symptoms were unchanged or worsened. RESULTS: A total of 41 subjects were included. Majority (85.4%) were female, the mean age was 48.95 ± 15.46 (range 22 - 77 years) and the median follow-up was 4 years (range 4 - 5 years). Constipation was the primary indication for biofeedback in 27/41 (65.9%), FI in 9/41 (22%) and "other" in 5/41 (12.1%). Within constipation, 55.6% reported long-term improvement as compared to 66.7% of FI and 80% of the other patients. There was borderline difference in the baseline EMG (3.11 ± 1.85 µV, improved, and 7.41 ± 11.01 µV, not improved, P = 0.06) but no significant difference in post-exercise resting (3.13 ± 3.21 µV, improved, and 4.28 ± 3.63 µV, not improved, P = 0.33) and contraction EMG between the two groups. CONCLUSIONS: Biofeedback is an important treatment tool in anorectal disorders. Over 50% of our subjects maintained their improvement 4 - 5 years after completing biofeedback therapy. A lower resting baseline EMG showed a trend of association with improvement in the long term.
ABSTRACT
Biofeedback is the treatment of choice for functional defecation disorders such as idiopathic chronic constipation and neurogenic fecal incontinence. The pre-existing biofeedback systems have many disadvantages. The aims of current project are, first, to develop the biofeedback system into the application software in the Windows environment, and, second, to assess the possibility of clinical usage for patients with functional defecation disorders. The hardware and software of the BASCO (Biofeedback Anal Sphincter Control) system were based on the signal measurement and signal processing of anal sphincter EMG (Electromyography). BASCO system was applied to 5 normal healthy controls and 20 patients with functional defecation disorders. Patients group was categorized as constipation group (N1=15) and incontinence group (N2=5). With use of current system, EMG-based biofeedback therapy was performed, and the outcome was analysed. Anal EMG signal data was processed by the software, and displayed in the monitor of personal computer. The software of EMG-display and database management were adequately operated. In N1 group, a paradoxical elevation or equalized activity of anal EMG pattern was shown in the simulated defecation. In N2 group, low electrical activity was shown. These findings were used for the EMG-based biofeedback therapy as a pilot study. The clinical symptoms were improved in 12 of N1 group and 3 of N2 group in the period of 3.7 (range, 1~12) months follow-up. In Conclusion, newly-developed BASCO system was adequately operated in the volunteer and patients groups. The multi-tasking and multi-processing functions were adequately shown in the real time. Current results could be used for clinical appraisal. Specifically, this system could be used for the practical application of biofeedback therapy in the patients with chronic constipation or fecal incontinence.
