[Examination of the rectosphincteric reflex by means of endoscopic electrical stimulation. A new device]

An endoscopic electrical stimulation method (the new method) for the examination of the rectosphincteric reflex was devised to overcome difficulties attributable to the manometric method using balloon stimulation. Safety of the electrical stimulation under the conditions used routinely, was confirmed symptomatically and histologically. It was found that the optimal parameters of electrical stimulation to obtain the recto-sphincteric reflex were: 1 ms, 20 Hz, 5 to 7mA, and for 3 sec. The degree of the reflex relaxation became less and the time lag of the response to the stimulation became longer, as the distance of the stimulation site from the anal verge was increased. These relationships were significant. In the cases which received anterior resection of the rectum, the rectosphincteric reflex was examined using the new method. In 12 of 39 cases the recto-sphincteric reflex was induced by stimulation at the oral side of the anastomosis. In all of them the reflex was observed at 9 or more months postoperatively. Incidence of postoperative reflex appearance tended to be higher after end-to-end anastomosis than after side-to-end anastomosis. In two cases which received Duhamel-Okamoto's operation and in one which received Soave-Denda's operation, it was possible to analyze the relationship between the stimulating site and presence or absence of the reflex-like phenomenon.