DELAYED COLONIC TRANSIT IN SPINAL CORD-INJURED PATIENTS MEASURED BY IN-111 AMBERLITE SCINTIGRAPHY

Objective: Constipation is a major problem for patients with chronic s pinal cord injury (SCI). However, it is not clear whether abnormal col onic transit is restricted to the rectosigmoid region or involves the entire colon. We assessed regional colonic transit with emphasis on th e ascending and transverse segments in patients with chronic SCI and c ompared the results with those of controls using scintigraphic techniq ues. Methods: Seven patients with SCI below T1 and 10 control subjects were studied after oral ingestion of a capsule containing indium-111- labeled Amberlite (Sigma Chemical, St. Louis, MO) pellets. The capsule was coated with a pH-sensitive polymer that prevents disintegration u ntil it reaches the ileocecal region. Assessments of the half-time of emptying and residence time of contents in ascending and transverse se gments mere made, as well as an assessment of the velocity of contents throughout the entire colon, including the descending colon. Results: A significantly slower half-time of emptying was found in SCI patient s ascending: 29 +/- 27 hr in SCI, 6.81 +/- 3.03 hr in controls, p < 0. 01; ascending + transverse: 42 +/- 12 hr in SCI, 15.3 +/- 7.16 hr in c ontrols, p < 0.01). The residence time of the median position of the c ontents was significantly prolonged in SCI patients (ascending: 31 +/- 23 hr in SCI, 8.75 +/- 4.68 hr in controls, p < 0.05; transverse: 26 +/- 3 hr in SCI, 5.0 +/- 4.4 hr in controls, p < 0.05). Overall, the v elocity of the median position of contents throughout the entire colon was significantly lower in SCI (0.63 +/- 0.33 cm/hr in SCI, 2.58 +/- 1.20 cm/hr in controls, p < 0.001. Conclusions: Patients with chronic SCI have prolonged colonic transit that involves the entire colon. Hen ce, treatment of constipation in these patients may need to include pr okinetic agents as well as local rectal maneuvers.