How a Stroke is Diagnosed in Dogs
A dog should be taken to a veterinarian immediately when it shows stroke-like symptoms. The veterinarian will perform a series of tests to rule out other possible causes of neurological signs. If no particular abnormality is identified quickly, additional tests will be necessary to determine whether or not a stroke has occurred. The dog will need to be hospitalized and stabilized while these diagnostic procedures take place.
Unfortunately, most strokes in dogs cannot be diagnosed simply by radiographs (X-rays) or routine blood tests. The only current way to accurately diagnose stroke in dogs is through brain imaging scans. These include computed tomography (CT/CAT scan) and magnetic resonance imaging (MRI). Most local veterinary clinics do not have the instruments necessary to conduct either a CT or an MRI. If a veterinarian suspects that a dog has had a stroke, the owner normally will be referred to a veterinary neurologist whose clinic has these specialized capabilities.
Other useful diagnostic tools include routine blood work (to identify systemic disease), arterial blood gas evaluation (to assess oxygenation of blood), coagulation profiles (to assess blood clotting parameters), skull radiographs (to identify fractures, especially in cases of trauma), blood pressure assessment, an electrocardiogram (ECG) (to detect heart rhythm irregularities) and analysis of the cerebrospinal fluid (a “spinal tap”).
CT and MRI scans will almost always provide the information necessary to diagnose a stroke. They also will help the veterinarian determine what type of stroke is involved. An ischemic stroke occurs when the blood supply to the brain has been compromised (such as by a clot, embolus or other obstruction), while a hemorrhagic stroke occurs when a blood vessel inside the brain bursts. The treatment protocol will depend upon which type of stroke has occurred.