Anorectal Profilometry with the Microtransducer

The reproducibility of anal sphincter manometry has been evaluated in 17 patients with a continuous pull-through technique using a miniature transducer mounted on a 2mm diameter Dacron catheter. Comparison was made with a conventional station pull-through technique using a 4mm diameter waterfilled microballoon connected to an external transducer. Parameters measured with the microtransducer (maximum resting pressure, squeeze pressure, functional sphincter length, area under high pressure zone, amplitude of rectosphincteric reflex) showed mean coefficients of variation from 3.2 to 5.7 per cent. Pressures measured with the microballoon were uniformly higher than those obtained with the microtransducer. The functional sphincter length was significantly shorter when measured with the microballoon (P less than 0.001). The microtransducer provides a highly accurate and reproducible method of anorectal profilometry that avoids many of the drawbacks associated with fluid-filled systems.