Differences between genders in colorectal morphology on CT colonography using a quantitative approach: a pilot study

Highlights

• Colon metrics in men and women can be reproducibly measured.

• Women referred to CTC after incomplete OC had more complex morphology than men.

• These pilot data may help explain the higher frequency of incomplete OC in women

Abstract

Purpose

To explore quantitative differences between genders in morphologic colonic metrics and determine metric reproducibility.

Methods

Quantitative colonic metrics from 20 male and 20 female CTC datasets were evaluated twice by two readers; all exams were performed after incomplete optical colonoscopy. Intra −/inter-reader reliability was measured with intraclass correlation coefficient (ICC) and concordance correlation coefficient (CCC).

Results

Women had overall decreased colonic volume, increased tortuosity and compactness and lower sigmoid apex height on CTC compared to men (p < 0.0001,all). Quantitative measurements in colonic metrics were highly reproducible (ICC = 0.9989 and 0.9970; CCC = 0.9945).

Conclusion

Quantitative morphologic differences between genders can be reproducibility measured.

Introduction

Incomplete optical colonoscopy (OC) has been reported in up to 20% of patients who undergo colon cancer screening [1] and is more common in women than in men [2], [3], [4], [5]. Higher rates of incomplete OC in women are thought to reflect differences in colonic morphology, including colonic length and tortuosity, based on subjective visual analysis and endoscopic experience [5], [6], [7], [8]. However, differences in morphology between genders have been difficult to measure quantitatively, as the colon can be distended in three dimensions, and the cecum, sigmoid, and transverse colon are variably mobile, depending on the presence and extent of various colonic mesenteries. A quantitative, reproducible method for assessment of colonic morphology would permit detailed evaluation of differences between men and women with incomplete OC. We therefore performed a pilot study using CT colonography (CTC) to explore differences between men and women for specific colonic metrics and also to determine the reproducibility of CTC for these metrics by measuring intra- and inter-reader reliability.