Lateral Medullary Syndrome: Uncommon Form of Brainstem Stroke

Abstract

Introduction and importance: Lateral medullary syndrome (LMS) is less common form of brainstem stroke. It is the result of occlusion of posterior inferior cerebellar artery (PICA). It is caused by atherosclerosis, thrombosis or emboli from another source. Case Presentation: A 60-year-old male patient presented to the emergency department with vertigo, vomiting, slurred speech, hiccups, and right side weakness associated with parasthesia for one day. He had past medical history of uncontrolled hypertension, and a smoking habit. The neurological examination revealed ataxia, right hemiparesis associated with parasthesia. Cranial nerve examination revealed right-sided slight ptosis, mouth deviation, and loss of sensory sensation on the right side of the face. Brain MRI showed right medullary infract consistent with lateral medullary syndrome. Electrocardiogram, echocardiography and vertebral artery color Doppler were normal. He was admitted to the neurology ward and was treated with Clexane 60mg SC, Aspirin 300 mg, neuroprotective agents, and antihypertensive treatment. After 6 days of medical treatment, his condition has improved massively (dysarthria and dysphagia disappeared). He was discharged for physical rehabilitation. Clinical discussion: Lateral medullary syndrome (Wallenberg syndrome) is one of the brainstem stroke syndrome caused by occlusion of PICA. Vertigo, vomiting, dysphagia, dysarthria, ipsilateral ataxia, Horner syndrome and contralateral hemiparesis define this syndrome. Brain MRI is necessary for diagnosis alongside the clinical syndrome. Conclusion LMS is rare form of brainstem stroke and carries favorable prognosis if early hospitalization and treatment is applied. Brain MRI including diffusion sequence is the most useful diagnostic tool for detecting LMS.