Computed Tomography Colonography Technique: The Role of Intracolonic Gas Volume

Figure 1

Selected images demonstrating the 4-point colonic distention grading scheme adapted from Burling et al. [5]. Grade 1 indicates complete collapse. Partial collapse (grade 2) was designated when the thickest portion of the haustral folds measured more than 4 mm in width or met within the lumen. Reasonable but suboptimal distention (grade 3) was defined as an easily visible slightly thickened colon wall, and optimal distention (grade 4) was designated when the colonic wall was thin and sharp.