A Case of Wallenberg Syndrome due to Vertebral Artery Dissection

Vertigo and nausea suddenly developed in a 33-year-old man without a relevant medical history. He reported that he had had throbbing headaches for 1 month. On admission, neurological examination revealed dysarthria, right Horner syndrome, and hypoesthesia of the left side of the face and of the left side of the body below the neck. Initial magnetic resonance imaging of the brain showed no areas of abnormal intensity on diffusion-weighted imaging, but magnetic resonance angiography showed a stringlike structure of the right vertebral artery. Acute infarction due to right vertebral artery dissection was diagnosed. Heparin sodium was immediately administered intravenously. Three days after symptom onset, magnetic resonance imaging-diffusion-weighted imaging of the brain clearly showed a high-intensity area in the right lateral medulla oblongata, a finding that confirmed the clinical diagnosis. This case emphasizes that vertebral artery dissection should be considered in patients with vertigo, especially young patients without risk factors for cerebrovascular disorders. The clinical history and neurological examination remain fundamental aspects of patient assessment in the era of advanced neuroimaging.