Neuroanatomical basis of Wallenberg syndrome.

Wallenberg syndrome, or lateral medullar syndrome, is the clinical presentation of the infarct in the territory of posterior inferior cerebellar artery. Its signs and symptoms include vertigo, nystagmus, diplopia, ipsilateral Horner syndrome, facial ruddiness and dry skin, dysphonia, dysphagia, dysarthria, ipsilateral loss of gag reflex, ipsilateral ataxia, ipsilateral impaired taste, ipsilateral facial pain and paresthesia, decreased ipsilateral blink reflex, contralateral hypoalgesia and thermoanaesthesia in the trunk and limbs; and ipsilateral facial hypoalgesia and thermoanaesthesia. Neuroanatomical knowledge is essential to its comprehension, study and diagnosis, because the classic neurological manifestations are easy to explain and understand if function and localization of affected anatomical structures are known as if the posterior cerebral circulation is.