Anatomy-related ratios predict colonoscopy incompleteness in similar examination conditions

Screening colonoscopy is one of the most popular modalities for screening and surveillance of colorectal cancer and other colon disorders.

To introduce new ratios to predict the colonoscopy course in patients with similar characteristics.

Five hundred screening colonoscopies (252 females and 248 males) were performed by an experienced endoscopist. Incomplete colonoscopies (without pathologic findings, i.e., disease-unrelated) were included in the study. Collected data was used to determine new ratios.

An examination was completed in 231 (91.7%) females (F) and 239 (96.4%) males (M). The majority of incomplete colonoscopies were discontinued in the sigmoid colon: 8 F (38.1%) and 4 M (44.4%) or in the descendosigmoid flexure: 4 F (19%) and 2 M (22.2%). We found statistically significant higher risk of incompleteness in females (p = 0.03), patients after 2 or more surgical treatments (p = 0.007) and in males with lower body mass index (BMI) (p = 0.01) (χ2 tests). Moreover, we discovered a statistically significant correlation with 2 or more previous surgical treatments in the female group (p = 0.02) (χ2 test). We calculated the incomplete colonoscopy anatomy-related (ICAR) and modified ICAR (MICAR) ratios. The range of ICAR and MICAR was 0-0.17; the number of incomplete examinations ranged from 0 to 1 failed out of 6 attempts (calculation: 100:17 = 5.88).

The ICAR and MICAR ratios reflect the various risk of colonoscopy incompleteness (i.e., disease-unrelated) and highlight the differences between patients in similar examination condition.