CASE REPORT: CLINICAL AND MRI FEATURES OF HEMORRHAGIC TRANSFORMATION OF AN ISCHEMIC CEREBROVASCULAR ACCIDENT IN A DOG

Alessandro Bellomo^1*Chiara Mattei¹Michele Capasso¹Marco Bernardini^1,2FEDERICA BALDUCCI¹

• ¹Ospedale Veterinario I Portoni Rossi s.r.l, Zola Predosa, Italy
• ²Department of Animal Medicine, Production and Health, School of Agricultural Sciences and Veterinary Medicine, University of Padua, Padua, Veneto, Italy

Hemorrhagic transformation (HT) is a known complication of human ischemic cerebrovascular accidents (CVAs), resulting from blood–brain barrier disruption and reperfusion. This report describes the magnetic resonance imaging (MRI) features of a clinically suspected HT after ischemic CVA in a dog.An eight-year-old spayed female mixed-breed dog presented with peracute onset of left-sided forebrain clinical signs. A brain MRI, performed within 12 hours from the onset of clinical signs, revealed a large area of restricted diffusion, almost undetectable in the other MRI sequences, encompassing the vascular territory of the left middle cerebral artery, suggesting a peracute ischemic CVA. In the subsequent 24 hours, the dog showed severe clinical deterioration, suggesting brainstem involvement. A 40-hour follow-up MRI revealed an extensive area of signal void on Susceptibility-Weighted Imaging in the same vascular territory, with severe mass effect, indicating HT of the previous ischemic CVA. Rapid and severe clinical deterioration in a dog previously diagnosed with ischemic CVA should raise suspicion of HT and warrant further MRI evaluation.