Tu2027 Topography and Characterization of Anal Ultraslow Waves (AUSWs) in Patients With Proctalgia Fugax. a Study Using High-Definition Anorectal Manometry (HDM).

Ano-rectal disorders are quite common in the general population. Although they are not life threatening conditions they do represent a certain social stigma and a reduced quality of life for the sufferer. The ano-rectal region is a continuously active area integrating the effects of smooth and striated muscle sphincters. The underlying physiology of muscle function contributing to ano-rectal competence is still poorly understood and there is room for a much better understanding so that treatments can improve. In this work we inserted a cylindrically shaped, liquid filled bag (7.5 cm long), mounted on a catheter into the anus and positioned it straddling the ano-rectal region in 20 healthy volunteers (10 females). A series of volume-controlled distensions (40ml/min to 40ml) were carried out and data on 16 cross-sectional area measurements at 5 mm apart and bag pressure were recorded. Provocative tests using squeeze and cough at bag volumes of 20, 30 and 40ml were also carried out. Results indicated that the procedure was safe and well tolerated. Ramp distension showed that the female ano-rectal sphincter requires a higher pressure (mean, 11mmHg) to open than in males (mean, 5mmHg) (P 0.05). The geometric profile during distensions showed almost the same pattern in all volunteers with proximal and distal narrow bands at low degrees of distension and shortening of the narrow zone at higher degrees of distension (figure1). Interindividual differences were observed in the behaviour of the external anal sphincter and the puborectal muscle during squeeze. However, during cough their behaviour was quite similar. This distensibility technique provided an important new way of studying the anal canal and hence may have a role in testing sphincter competence in patients with incontinence and anorectal dysfunction.