Fig. 2From: Development of colonic transit time and ultrasound imaging tools as objective indicators for assessing abnormal defecation associated with food intake: a narrative review based on previous scientific knowledgeClassification of opaque marker retention in the large intestine on X-ray. A method has been developed to divide the large intestine into the right colon, left colon, sigmoid colon, and rectum and to classify disorders into total colon stagnation, right colon stagnation, left colon stagnation, and faecal discharge disorder according to marker retention at each siteBack to article page