肛門電気刺激療法の実験的および臨床的検討

Abstract

雌性正常イヌをα-chloralose urethane麻酔下に肛門電気刺激を行った結果, 生理的食塩水の持続的注入時にみられる膀胱の周期的な反射性収縮を抑制するためには5～10 Hzの低周波数刺激が適当であるとの結果をえた.過活動型膀胱が認められる切迫性尿失禁患者18例を以下の刺激条件にて肛門電気刺激を行った.持続時間0.2 msec, 周波数5 Hz, 強度は患者の耐えうる最大強度(30～150 V), 30分間刺激を週5回の頻度で10回行った.18例中12例に尿失禁の消失がみられ, 肛門電気刺激前後の初発尿意量, 最大膀胱容量に有意の増加が認められたが, 最大尿道閉鎖圧, 残尿量に関しては, 有意の増減はみられなかった.症例を不安定膀胱群と神経因性膀胱群に分類して比較を行った場合, 自覚症状の改善率に関しては, 両群間に有意差はみられなかったが, 神経因性膀胱群では初発尿意量, 最大膀胱容量に有意の増加が認められた.塩酸terodilineなどの薬剤併用群と非併用群とに分類した場合(併用群は18例中11例), 尿失禁の改善率は併用群に有意に高かった

To determine the most effective parameter of functional electrical stimulation of the anal sphincter (FES), the present study was carried out in female mongrel dogs anesthetized with alpha-chloralose urethane. When spontaneous and rhythmic micturition contractions of the bladder were present, they were more effectively inhibited by the stimulation with low frequency (5 to 10 Hz). Based on the results of this experiment 18 patients with urge incontinence were treated by maximal electrical stimulation with the following parameters. The duration for each stimulus was 0.2 msec, frequency 5 Hz, amplitude 30 to 150 volts. Every patient received ten treatments for two weeks, each lasting for 30 minutes. A clinical cure for urge incontinence was noted in 12 patients. As for urodynamic studies, FES increased significantly the volumes of the first desire to void (FDV) and maximum desire to void (MDV); however, it did not increase significantly the maximum urethral closure pressure or residual urine volume. Eighteen patients were divided into two groups; an unstable bladder group and a neurogenic bladder group. In the latter, the increases in volumes of FDV and MDV were significant. Second, 18 patients were divided into two groups according to the administration of lack of anticholinergic agents. For subjective symptoms, the rate of improvement of urge incontinence was significantly higher in the group administered the agents. These findings suggested that FES was very useful for the treatment of urge incontinence, with its efficacy augmented by the administration of anticholinergic agents.