Colonic Transit Time in 64 Iranian Patients with Idiopathic Chronic Constipation

Background and objective- Estimation of the colonic transit time (CTT) or the transit time of various bowel segments helps in the pathological diagnosis of constipation and in determining the required treatment. The aim of this study was to recognize the mechanism and type of passage of feces in various segments of the large bowel among patients who attended different GI clinics with constipation.Methods-Among the patients with chronic constipation and no signs of organic or endocrine disease, the time taken for evacuation of the colon (CTT) was estimated by the ingestion of ten radio-opaque markers, each 1-3 mm in length, for 6 consecutive days after which a plain abdominal X- ray was taken on the seventh day. A comparison was then made between the time required for evacuation of the markers from the colon and the patient’s age, sex, frequency of defecation, severity and pressure at the time of defecation.Results-A total of 64 patients (28 male and 36 female) with a mean age of 37.3 years and a range of 13-76 years were included in the study. The frequency of defecation was less than once a week, once a week and twice a week in 7, 41 and 16 patients, respectively. Moreover, 26 patients had no pressure on defecation. Among the 64 persons under study, 37 had abnormal colonic transit time (over 34 hours). The remaining 27 patients who complained of severe constipation were found to have a normal transit time. The duration of abnormal defecation was unrelated to sex, chronicity of the disease or pressure on defecation. Delayed bowel evacuation in the right colon, left colon and rectosigmoid was found in 8, 26 and 15 patients, respectively. Conclusion-The estimation of bowel evacuation time using radio-opaque markers can be very helpful in determining the mechanism, pathophysiology and treatment of constipation. In addition, it is a helpful method in the recognition of false cases in patients who complain of severe constipation but who have a normal bowel transit time. Thus it is possible to use suitable treatment according to the motility disorder of the different areas of the bowel.