Segmental colonic transit studies: comparison of a radiological and a scintigraphic method

OBJECTIVE: Colonic transit studies are used to diagnose slow transit constipation (STC) and to evaluate segmental colonic transit before segmental or subtotal colectomy. The aim of the study was to compare a single X-ray radio-opaque marker method with a scintigraphic technique to assess total and segmental colonic transit in patients with STC. METHOD: Thirty-one female patients (median age 46 years) with severe constipation and a prolonged or borderline prolonged colonic transit time on radio-opaque marker study were included in the study. They were subsequently investigated with (111)Indium-DTPA colonic transit scintigraphy, with a median time between the investigations of 4(range 1-27) months. Normal values of healthy female controls were used for comparison. RESULTS: There was no difference between the two methods in terms of prolonged or normal total colonic transit time. Twenty-nine of 31 female patients had a prolonged transit time only in one or two segments on the marker study. On scintigraphy, the transit time was prolonged for patients in the left (P < 0.05 to P < 0.001), but not in the right colon. With respect to prolonged or normal segmental transit time, there was a significant difference between the two methods only in the descending colon (P = 0.02). However, the results varied considerably for individual patients. CONCLUSION: Segmental colonic delay was a common finding. The two methods gave similar results for groups of patients, except in the descending colon. The variation of the results for individuals suggests that a repeated transit test may improve the assessment of total and segmental transit.