Radiographic changes after colonoscopic decompression for acute pseudo-obstruction

PURPOSE: Colonoscopy has been the principal tool for decompression in acute colonic pseudo-obstruction, known as Ogilvie's syndrome. The objectives of this study were to determine the immediate effect of colonoscopy on the ce cal diameter (measured on supine radiographs) and to delineate possible cor relations in the diameters of dilated segments of the colon. METHODS: The c harts and radiographs of 24 patients who had colonoscopic decompression for acute colonic pseudo-obstruction between 1992 and 1997 at the San Diego Ve terans Affairs Medical Center and the University of California, San Diego H ospitals were reviewed. We measured cecal, transverse, descending, and sigm oid colon diameters on serial radiographs up to the point of clinical resol ution. RESULTS: Mean +/- standard deviation cecal diameter change (between initial and post-decompression films) was -2 +/- 3.4 cm at four hours and - 2.2 +/- 3.3 cm one day after decompression. On the daily radiographs betwee n colonoscopic decompression and clinical resolution, there was a close cor relation beta een the diameter of the cecum and that of the transverse colo n (P < 0.05). There was no correlation between the cecal diameter and that of the descending or sigmoid colon. CONCLUSIONS: Colonoscopic decompression only causes a small decrease in cecal size in the patient with acute colon ic pseudo-obstruction. Dilation patterns of the cecum and transverse colon are significantly correlated in acute colonic pseudo-obstruction. This corr elation provides additional support to the contention that the same pathoph ysiology affects these two segments of the colon.