Teniae Coli–based Circumferential Localization System for CT Colonography: Feasibility Study

Abstract

This HIPAA-compliant study, with institutional review board approval and informed patient consent, was conducted to retrospectively develop a teniae coli-based circumferential localization method for guiding virtual colon navigation and colonic polyp registration. Colonic surfaces (n = 72) were depicted at computed tomographic (CT) colonography performed in 36 patients (26 men, 10 women; age range, 47-72 years) in the supine and prone positions. For 70 (97%) colonic surfaces, the tenia omentalis (TO), the most visible of the three teniae coli on a well-distended colonic surface, was manually extracted from the cecum to the descending colon. By virtually dissecting and flattening the colon along the TO, the authors developed a localization system involving 12 grid lines to estimate the circumferential positions of polyps. A sessile polyp would most likely (at 95% confidence level) be found within +/-1.2 grid lines (one grid line equals 1/12 the circumference) with use of the proposed method. By orienting and positioning the virtual cameras with use of the new localization system, synchronized prone and supine navigation was achieved. The teniae coli are extractable landmarks, and the teniae coli-based circumferential localization system helps guide virtual navigation and polyp registration at CT colonography.

A novel colon wall flattening model for computed tomographic colonography: method and validation

“…For example, in the studies [30][31], the folds were detected by thresholding the curvatures in the 3D colon representation, while in [32], the detection task was fulfilled by using a Gabor filter on a 2D unfolded colon representation. In this exploratory investigation, a local elevation mapping (LEM) method is proposed for the colonic fold detection and segmentation.…”

“…In the previously reported literature, approaches for TC extraction can be categorized into two groups, manual drawing and automatic extraction [30][31] [32]. As far as the automatic approaches to be concerned, most of the previous studies suggested to use curvature filter or Gabor filter [32] for surface analysis to get the TC lines on the colon.…”

Automated teniae coli detection and identification on computed tomographic colonography

“…13, we selected TO from the manually labeling results provided by radiologist, then derived the corresponding TM and TL in one-third of the circumference location of the colon. When calculating the RMSE of their method, 13 only TM and TL were measured, since the TO itself was the reference standard. The proposed method achieved an average normalized RMSE ( 6 standard deviation, [95% confidence interval]) of 4.87% ( 6 2.93%, [4.05% 5.69%]), while Huang's method 13 had an average normalized RMSE of 5.65% ( 6 1.94%, [5.60% 5.71%]).…”

“…When calculating the RMSE of their method, 13 only TM and TL were measured, since the TO itself was the reference standard. The proposed method achieved an average normalized RMSE ( 6 standard deviation, [95% confidence interval]) of 4.87% ( 6 2.93%, [4.05% 5.69%]), while Huang's method 13 had an average normalized RMSE of 5.65% ( 6 1.94%, [5.60% 5.71%]). The difference between these two methods is not statistically significant (p ¼ 0.08).…”

“…Existing methods for extracting teniae coli can be grouped into two categories, manual and automatic. Huang et al 13 manually extracted TO, the most visible tenia coli on a well-distended colon. They first looked for the TO in the cecum by locating the ileocecal valve.…”