External carotid steal and lateral medullary infarction--is there a pathogenetic connection?

The case of a patient with occlusion of the external carotid artery is reported; he suffered from vertebrobasilar insufficiency with Wallenberg's syndrome. Arteriography showed stealing of intracranial blood from the vertebral artery via the occipital artery, and thromboendarterectomy was successfully performed. Since no localised processes could be demonstrated could the lateral medullary infarction be due to the haemodynamic changes? In cases of external carotid steal thromboendarterectomy might be the appropriate treatment.