High-resolution manometry in the evaluation of anorectal disorders: A simultaneous comparison with water-perfused manometry

INTRODUCTION: High-resolution manometry (HRM) combined with novel interpretive software allows for the interpolation of manometric recordings into highly detailed topographical plots of intraluminal pressure events relative to time and location. To date, HRM has been used primarily in the study of esophageal disorders and has been shown to provide greater physiologic resolving power compared with standard manometric techniques. This preliminary feasibility study is the first report evaluating HRM and simultaneously performed water-perfused manometry (WPM) in patients referred for anorectal manometry (ARM). METHODS: Consecutive patients referred for ARM underwent simultaneous WPM and HRM. WPM was performed using a 6-cm sleeve assembly with side-holes spaced at 3-cm intervals. HRM was performed using the ManoScan™ system (Sierra Scientific Instruments, Los Angeles, CA) consisting of a 36-channel catheter with sensors spaced at 1-cm intervals. Space-time pressure data were displayed in topographic form using ManoView™ analysis software that is part of the ManoScan system. Measurements of anal sphincter pressure at rest, during voluntary contraction, and during 40-mL rectal balloon distension were compared. RESULTS: A total of 29 patients were studied. Indications for manometry were constipation (19), incontinence (7), and fecal soilage (3). Simultaneously recorded resting, squeeze, and relaxation pressures showed the two methods to be significantly correlated although anal sphincter pressures recorded by HRM tended to be higher than those recorded with WPM. HRM provided greater resolution of the intraluminal pressure environment of the anorectum. CONCLUSIONS: These preliminary observations demonstrate that anorectal HRM highly correlated with WPM measurements and provided greater anatomic detail.