OBJECTIVE: The aim of this prospective study was to compare the accuracy of abdominal computed tomography (CT) and colonoscopy in diagnosing colonic pathology in an elderly population. METHODS: Patients over the age of 70 for whom an outpatient diagnostic colonoscopy had been requested, were invited to attend for a CT scan of the abdomen following oral colonic preparation. CT was carried out within 1 month of the colonoscopy and all images were evaluated by a single consultant radiologist with no prior knowledge of the colonoscopy result. RESULTS: Of 72 patients who fulfilled entry criteria and attended for colonoscopy, 55 (29 female) had abdominal CT of the abdomen (mean age 76.6 years, range 70-92). Colonoscopy was successful in 67% of cases and the following colonoscopic diagnoses were made: diverticular disease (26), normal (14), colonic carcinoma (6), polyps (9) colitis (2) and angiodysplasia (1). There was agreement between colonoscopic and CT diagnoses in 38 patients (69%) including all those with carcinoma of the colon. There was disagreement in 12 patients with diverticular disease, CT missed three polyps in three patients and angiodysplasia in one patient. CT provided additional important information in 9 patients: gastric leiomyosarcoma (1), aortic aneurysm (1), absence of metastases (3), liver metastases (2), cirrhosis and portal hypertension (1) and a large pleural effusion (1). One patient thought to have a carcinoma of the colon by both techniques was subsequently found to have a diverticular mass at laparotomy. Two patients undergoing colonoscopy had colonic perforations and one of these died. CONCLUSION: CT may provide an alternative to colonoscopy in diagnosis of colonic disease in the elderly population.
OBJECTIVE: The aim of this prospective study was to compare the accuracy of abdominal computed tomography (CT) and colonoscopy in diagnosing colonic pathology in an elderly population. METHODS:Patients over the age of 70 for whom an outpatient diagnostic colonoscopy had been requested, were invited to attend for a CT scan of the abdomen following oral colonic preparation. CT was carried out within 1 month of the colonoscopy and all images were evaluated by a single consultant radiologist with no prior knowledge of the colonoscopy result. RESULTS: Of 72 patients who fulfilled entry criteria and attended for colonoscopy, 55 (29 female) had abdominal CT of the abdomen (mean age 76.6 years, range 70-92). Colonoscopy was successful in 67% of cases and the following colonoscopic diagnoses were made: diverticular disease (26), normal (14), colonic carcinoma (6), polyps (9) colitis (2) and angiodysplasia (1). There was agreement between colonoscopic and CT diagnoses in 38 patients (69%) including all those with carcinoma of the colon. There was disagreement in 12 patients with diverticular disease, CT missed three polyps in three patients and angiodysplasia in one patient. CT provided additional important information in 9 patients: gastric leiomyosarcoma (1), aortic aneurysm (1), absence of metastases (3), liver metastases (2), cirrhosis and portal hypertension (1) and a large pleural effusion (1). One patient thought to have a carcinoma of the colon by both techniques was subsequently found to have a diverticular mass at laparotomy. Two patients undergoing colonoscopy had colonic perforations and one of these died. CONCLUSION: CT may provide an alternative to colonoscopy in diagnosis of colonic disease in the elderly population.