Computed Tomographic and Radiographic Characteristics of Aortic Lesions in 42 Dogs With Spirocercosis

Abstract

Spirocerca lupi is a common cause of vomiting, regurgitation, and sudden death in dogs that live in tropical or subtropical regions. Sudden death due to aortic rupture may occur with no preceding clinical signs. The purpose of this prospective study was to compare radiographic and computed tomographic (CT) characteristics of aortic lesions in a cohort of 42 dogs with endoscopically confirmed spirocercosis. Dorsoventral and right lateral recumbent thoracic radiographic findings were compared with pre- and postcontrast thoracic CT findings. Aortic mineralization was detected using CT in 18/42 dogs (43%). Three dogs had faint diffuse aortic wall mineralization. Using CT as the reference standard, radiographs had a sensitivity and specificity of 6% and 96%, respectively, for detecting aortic mineralization. A total of 20 aortic aneurysms were detected using CT in 15/42 dogs (36%). Using CT as the reference standard, radiographs had a sensitivity and specificity of 86% and 56%, respectively, for detecting aortic aneurysms. Respiratory motion, aortic displacement by esophageal masses and Spirocerca nodules adjacent to the aorta mimicked aneurysm formation on radiographs. Aortic thrombi were seen in two dogs in postcontrast CT images. Findings from this study indicated that aortic mineralization and aneurysm formation are common in dogs with spirocercosis. Findings also supported the use of pre- and postcontrast CT as effective methods for detecting and characterizing these lesions.

Aortic to caudal vena cava ratio measurements using abdominal ultrasound are increased in dogs with confirmed systemic hypertension

“…In human medicine, systemic hypertension has been implicated in causing aortic dilation, which can lead to aneurysm and dissection, but aortic aneurysm with or without dissection has been infrequently reported in the veterinary literature. Reports in the older literature and one more recent study describe cases with aneurysmal dilatation of the thoracic aorta associated with Spirocerca lupi . Echocardiographic identification of aortic aneurysm was found in one dog associated with systemic hypertension, and in another hypertensive dog presenting for posterior paresis with concurrent thoracic aortic dissection and abdominal aortic thromboembolism .…”

Invited Review—computed Tomographic Angiography (Cta) of the Thoracic Cardiovascular System in Companion Animals

“…U ntil recently, CT applications for the thorax were mostly limited to morphologic evaluation of the chest wall, mediastinum, vessels, and lung parenchyma for differentiating normal from pathological conditions in companion animals . With the increased availability of multidetector‐row CT (MDCT) scanners with up to 320 detector rows that allow image acquisition with high temporal and spatial resolution, the utilization of this modality will likely rise for evaluating the thoracic cardiovascular system in companion animals and has been used in initial case reports and studies …”

The Efficacy of a Topically Applied Imidacloprid 10 % / Moxidectin 2.5 % Formulation (Advocate®, Advantage® Multi, Bayer) against Immature and Adult Spirocerca lupi Worms in Experimentally Infected Dogs

“…Kok et al (2010) have shown that even in animals that responded positively to treatment for the prevention of oesophageal spirocercosis, damage to the thoracic aorta still occurred and could only be quantified during postmortem examination of the aorta. Kirberger et al (2013) have shown that computed tomographic and radiographic procedures can be used to detect aortic lesions but these are likely to be of value mainly when gross lesions are present. These results obtained during an experimental infection confirm those of Le Sueur et al (2010) who reported on the high efficacy of an imidacloprid 10 %/moxidectin 2.5 % spot-on to prevent infection with S. lupi in a large population of young dogs naturally exposed to S. lupi on Réunion Island.…”