title: Computed tomographic pneumocolonography in normal dogs.
abstract: 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 (cm(2) ) 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.
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, 95615.
authors.forename: Michele A
authors.initials: MA
authors.lastname: Steffey
authors.forename: Leticia
authors.initials: L
authors.lastname: Daniel
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Taylor
authors.forename: Rachel X
authors.initials: RX
authors.lastname: Chen
authors.forename: Allison L
authors.initials: AL
authors.lastname: Zwingenberger
mesh_terms: D000818:Animals; D003106:Colon / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic / Q000379:methods / Q000662:veterinary*; D018592:Cross-Over Studies; D004285:Dogs; D007327:Insufflation / Q000379:methods / Q000662:veterinary; D008297:Male; D011446:Prospective Studies; D011897:Random Allocation; D014463:Ultrasonography
keywords: computed tomography; dog; large bowel; pneumocolonography