Scintigraphic defecography: quantitative and dynamic assessment of anorectal function

Abstract

PURPOSE: Conventional assessment of anorectal function with defecating videoproctography is semiquantitative and the high radiation exposure precludes prolonged or repeated testing. The aim of this study was to develop a dynamic scintigraphic method of assessing anorectal function. METHODS: Fourteen patients with fecal incontinence, 18 patients with chronic constipation, and 8 control subjects were assessed by scintigraphicdefecography. This involves introduction of a technetium-99m-radiolabeled artificial stool into the rectum of the subject and acquisition of gamma camera images during evacuation. RESULTS: Mean evacuation rate was 2.8 percent/second in incontinent patients and 0.9 percent/second in constipated patients (P < 0.001). The mean anorectal angles were 136 degrees and 133 degrees, respectively. There were 18 cases of pelvic floor descent and 6 rectoceles. Scintigraphicdefecography provides quantitative information on rectal evacuation. Anorectal angle and pelvic floor movement can be examined. The radiation dose to pelvic organs is significantly less than with videoproctography. CONCLUSION: We believe that scintigraphic defecography is the investigation of choice for objective and dynamic assessment of anorectal function