Chapter 40 - Medullary infarcts and hemorrhages

Summary

Since the first description of Wallenberg's syndrome more than 100 years ago, clinical and pathological findings of lateral medullary infarction (LMI) have been sporadically reported. Dizziness and ataxia are one of the most common symptoms/signs of lateral medullary infarction (LMI). Other symptoms/signs include nystagmus and ocular motor abnormality, dysphagia, dysarthria, hoarseness, nausea/vomiting, and hiccup. In patients with normal angiographic findings, atherothrombotic occlusion of a perforating artery itself seems to be the mechanism of infarction. Medial medullary infarction is usually caused by occlusion of penetrating branches associated with an atherosclerotic distal vertebral artery (VA) or vertebral arteries-basilar artery (VA-BA) junction. Lateral and medial medullary infarction may occur simultaneously or consecutively. Spontaneous primary medullary hemorrhage is rare. Although the causative role of hypertension is controversial, autopsy and imaging studies illustrate that hypertensive medullary hemorrhage does exist. Cavernous angiomas are a relatively frequent cause of medullary hemorrhage.