Computed Tomographic Pneumocolonography In Normal Dogs

Steffey MA, Daniel L, Taylor SL, et al.

Veterinary Radiology & Ultrasound 2015;56:278-285.

Objectives of this prospective study were to describe effects of varying technical components that may contribute to an optimal protocol for computed tomographic pneumocolonography (CTP) in dogs, and to develop a standardized methodology for CTP as a future potential diagnostic tool in canine clinical patients with large bowel disease. Eight purpose-bred intact male hound cross-research dogs were enrolled and randomized to groups based on variables of pressure/body position (n = 4) and insufflation time (n = 4). For each segment of large bowel (rectum, colorectal junction, descending colon, transverse colon, ascending colon), the adequacy of bowel preparation, % of bowel lumen filled with fecal material, and bowel tortuosity or folding were assessed. Measurements of bowel wall thickness (cm), cross-sectional bowel lumen diameter (cm), and cross-sectional bowel luminal area (cm2) were obtained at standardized locations within the large bowel. False discovery rates (FDR) were calculated to adjust for multiple testing. Values of FDR < 0.05 were considered significant. Differences in mean cross-sectional area and diameter and bowel wall thickness under increasing pressure were not significant after adjusting for multiple testing; some had raw p values <0.05. Ascending colon diameter and ascending colon area significantly increased with insufflation time (FDR < 0.05). No other response variables showed a significant change with insufflation time. The optimal insufflation pressure for maintaining pneumocolon in this study was determined to be 20 mmHg. CTP is a feasible technique to provide consistent distension for imaging of the large bowel and further study on application of CTP in clinical patients is warranted.