Stroke is the result of decreased perfusion to the entire brain or to a specific region of the brain.1 Pathologically, there are ischemic and hemorrhagic types of stroke.2 Ischemic stroke is the result of vascular occlusion secondary to a thrombus or embolus, whereas hemorrhagic stroke is the result of bleeding.1 Ischemic stroke has become increasingly diagnosed in dogs. Common MRI characteristics associated with ischemic stroke include a well-defined, intraparenchymal lesion that is hyperintense on T2W and T2W fluid-attenuated inversion recovery sequences and hypointense on T1W sequences, with little to no enhancement.2,3 Common sites for ischemic stroke include the cerebellum,3–5 caudate and lentiform nuclei and the intervening internal capsule,6 and thalamus.7 On the basis of the arterial supply to the brain, ischemic strokes in these brain regions are most likely the result of vascular disruption of the rostral cerebellar, lenticulostriate, and other penetrating arteries, respectively. Despite the increased detection of ischemic stroke in dogs, information in the veterinary literature has primarily included information regarding the affected vasculature on the basis of the anatomic distribution of a lesion observed in MRI images. Consequently, little information is known about breed predispositions of stroke. In 1 study8 of stroke in dogs, Greyhounds and Cavalier King Charles Spaniels were overrepresented. In that study,8 hypertension and a hypercoagulable state were frequently detected in affected dogs.
In our experience, ischemic stroke occurs more frequently in Greyhounds than in other dog breeds. The objective of the study reported here was to retrospectively determine the prevalence of ischemic stroke in Greyhounds; determine whether Greyhounds are predisposed to ischemic stroke, compared with a group of other breeds including mixed-breed dogs (non-Greyhounds); and determine whether affected Greyhounds have coagulation system abnormalities or systemic hypertension.
Apparent diffusion coefficient
3.0-T Signa HDx, GE Healthcare, Waukesha, Wis.
1.0-T Genesis Signa, GE Healthcare, Waukesha, Wis.
1.5-T Signa Excite, GE Healthcare, Waukesha, Wis.
1.5-T Magnetom Symphony Maestro Class, Siemens, Erlangen, Germany.
GraphPad Prism, version 5, GraphPad software, La Jolla, Calif.
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