Scintigraphic assessment of neorectal motor function.

Colectomy, mucosal rectectomy, and ileal pouch-anal anastomosis have become alternatives to proctocolectomy and ileostomy for patients with ulcerative colitis or polyposis coli. The aim of this study was to develop a scintigraphic technique for assessment of the "neorectal" motor function of such patients. An artificial stool, consisting of a 7.5% dispersion of aluminum magnesium silicate in water, was labeled with 1 mCi [99mTc]sulfur colloid and instilled into the neorectum. Static pre- and postevacuation scans and dynamic acquisition scans during evacuation were taken with the patient seated on a commode. The imaging provided good anatomic definition of the pouch and quantitated the usual rate and percentage of neorectal evacuation at about 10 ml stool/sec and 60% of instilled stool, respectively. This technique appeared to be a safe, simple, useful tool for assessing the neorectal motor function of patients with ileal pouch-anal anastomosis.