Evaluation of Azygos Vein to Aorta Ratio using Multi-Detector Computed Tomography in Dogs

Hyunyoung Park, Jungyong Kim, Soochan Kim, Woochang Jeong, Jungwoo Lee, Sooyoung Choi, Hojung Choi, Youngwon Lee
2020 Journal of Veterinary Clinics  
The purpose of this study is to evaluate the azygos vein to aorta diameter ratio (AV/AO ratio) in healthy dogs and dogs with diseases that may cause azygos vein dilation. The normal groups included eleven healthy beagle dogs and eleven small breed dogs. The abnormal group included 43 dogs that had diseases with high right atrial pressure (RA group), obstruction of cranial or caudal vena cava (CVC group) and porto-azygos shunt group (PSS group). The diameter of AV and AO were measured at three
more » ... tes on thoracic CT images; the level of the cranial endplate of 12 th thoracic vertebra (TV level), the tracheal bifurcation (TB level) and the insertion to the cranial vena cava (CrVC level). The AV/AO ratio at the CrVC level had significantly higher values than those at the TV and TB levels in the normal groups. The AV/AO ratios of TV and TB levels in the CVC group and the values at all measurement sites of the PSS group were significantly higher than the normal groups. AV/AO ratio will be a useful factor for the evaluation of various clinical conditions that change the AV diameter with respect independent to the body weight in dogs.
doi:10.17555/jvc.2020. fatcat:sn3bu44n3naqdftpm3d6rxk35a