[Cerebellar infarction].

Cerebellar infarcts have long been underrecognized both clinically and neuroradiologically. In approximately a quarter of cases, they are oedematous and may require, unlike other cerebral infarcts, a sometimes life saving surgery when there are signs of brain stem compression. Benign infarcts are more frequent, but inaugural symptoms are identical: vertigo, headache, vomiting, unsteadiness, and dysarthria of sudden onset. Brain stem and occipital symptoms can be associated and are sometimes prominent. The infarct can be shown by CT but MRI is the method of choice for early recognition, precise delineation, and detection of associated brain stem infarcts. Prognosis is good when the infarct is restricted to the cerebellum, and poor when the brain stem is involved, a fact which should be taken into account in the surgical decision making. Cardiac emboli are the leading cause followed by atherothrombotic occlusions. These are usually located in the intracranial part of the vertebral artery and less frequently in the lower basilar artery, and are therefore inaccessible to prophylactic vascular surgery.