Diagnostic performance of computed tomography colonography following incomplete colonoscopy and its associated...

Incomplete colonoscopy presents an important clinical challenge, as segments of the colon that are not visualised may contain significant pathology. Computed tomography colonography (CTC) provides a minimally invasive alternative for comprehensive luminal evaluation, but local evidence regarding its diagnostic yield remains limited. This study aimed to evaluate the diagnostic yield of CTC following incomplete colonoscopy and to determine its associated factors with demography.

A retrospective cohort study was conducted among 93 adult patients who underwent CTC after incomplete colonoscopy between 2018 and 2023 at Hospital Tengku Ampuan Afzan, Kuantan. Patient demographics, prior surgical history, CTC findings and lesion characteristics were analysed using descriptive statistics, Chi-square and Fisher's exact tests.

CTC demonstrated a diagnostic yield of 21.5%. In this cohort, females accounted a 58.1% of the population. Polyps were the most frequent pathology, followed by diverticulosis, segmental wall thickening, and a single case of colorectal mass. Statistical analysis showed no significant association between abnormal findings and demographic factors such as age, gender, ethnicity, previous abdominal surgery, clinical indications, or most proximal colonoscopic intubation (p >0.05). Although statistical significance was not significant, abnormalities were more often detected in older patients and when colonoscopic intubation was confined to the rectosigmoid colon.

CTC detected clinically important finding in more than one-fifth of patients, reconfirming its role as a valuable adjunct when colonoscopy is incomplete. These results showed polyps and diverticulosis as the main abnormalities with no clear predictors from patient factors. Larger prospective studies are needed to refine patient selection and optimise imaging quality in local setting.