The production and clinical features of a chronic stroke model in experimental primates.

The characteristics of stroke in baboons produced by transcranial occlusion of the middle cerebral artery were studied by clinical examination and serial cinematographic studies, the animals being maintained for three years following the stroke. The characteristic deficit in all animals was an initial, fairly dense faciobrachial weakness with, in a few instances, some accompanying leg weakness for a few days, rapidly improving over the first few months. Some animals retained very evident arm weakness; most animals retained weakness of the face; the majority showed recovery of reaching and placing reactions and some movement in all joints of the upper limb, although fine movements of the fingers remained invariably impaired. Homonymous hemianopia, at least to attention, also appeared to be characteristic, but all of the animals recovered a normal gait and leaping was regained. The close correlation between this and human stroke appears to confirm that middle cerebral artery occlusion in the baboon is a reliable, repeatable and acceptable stroke model.