The majority of strokes occur when blood vessels to the brain become narrowed or clogged with fatty deposits called plaque. This cuts off blood flow to brain cells. A stroke caused by lack of blood reaching part of the brain is called an ischemic stroke.
Dogs resemble humans in basic anatomy of a large-sized brain, its vascular structure and a high ratio of white compared to grey matter. Dogs age naturally and, as humans, they experience diseases of longevity such as cardiovascular disease and diabetes mellitus. They are also exposed to similar risk factors for stroke, including obesity, hypertension and environmental exposures such as pollution and passive smoking.
Ischaemic stroke seems to be less common in dogs than in humans. The reasons for this remain unclear, but possible explanations could the rare occurrence of atherosclerosis in dogs and the rapid dissolution of clots in dogs.1
Dogs affected by cerebellar ischaemic stroke typically present with a variety of neurological signs characterised by ataxia, head tilt, and nystagmus. In dogs with these neurological problems, cerebellar ischaemic stroke is an important differential diagnosis, and neuroimaging investigations are indicated. The clinical signs are usually sudden, non-progressive, and a gradual improvement is typically seen, although further neurological deterioration may develop within minutes to hours, or rarely up to days, of the acute event due to progressive cell death and a growing brain oedemaAlthough dogs are often severely compromised at presentation, short-term prognosis is excellent and rapid clinical improvement may be observed within the first week following the ischaemic stroke.2
Although dogs are often severely compromised at presentation, short-term prognosis is excellent and rapid clinical improvement may be observed within the first week following the ischaemic stroke.2
- Spontaneous ischaemic stroke lesions in a dog brain: neuropathological characterisation and comparison to human ischaemic stroke. Acta Vet Scand. 2017; 59: 7. Published online 2017 Jan 13. doi: 10.1186/s13028-016-0275-7
- Neurological signs in 23 dogs with suspected rostral cerebellar ischaemic stroke. Acta Vet Scand. 2016; 58: 40. Published online 2016 Jun 7. doi: 10.1186/s13028-016-0219-2