Implications of Computerized Tomography Colonography in Fully Intended but Aborted Optical Colonoscopy – a Retrospective Case-Control Study

If a complete optical colonoscopy (OC) cannot be performed, an alternative diagnostic method should be considered.The aim of this retrospective chart review study was to investigate the surgical and interventional endoscopic implications of CT colonography (CTC) after fully intended but aborted OC.302 patients with CTC after an incomplete OC were compared to sex-matched controls who underwent a complete OC by the same examiner in the same year. The most common indications were preventive colonoscopy (29.1%) and pathological iFOBT (9.6%). The most common reasons for OC discontinuation were suspected adhesions (n=64) and a long sigmoid colon ± non-inflammatory diverticula (n=59). OC discontinuation was most prevalent in the sigmoid colon (n=149, 49.3%). Adenoma detection rates in patients undergoing preventive colonoscopy were 9.6 and 26.9 per cent in the CTC and the control groups, respectively (p<0.01). A total of 384 extracolonic CT findings were identified in 197 patients (65.2%) including 373 benign (97.1%) and 11 potentially malignant findings (2.9%). However, only two of these could be confirmed histologically.In our cohort, CTC revealed only a small number of (pre-)malignant (extra-)intestinal findings. Therefore, we recommend a limited use of CTC, depending on the indication and the local findings that led to the discontinuation of OC.