Spontaneous Isolated Dissection of the Posterior Inferior Cerebellar Artery Presenting with Lateral Medullary Infarction

Background: Spontaneous isolated dissection of the posterior inferior cerebellar artery (PICA) is rare and presents with variable clinical course and prognosis. We report a case of spontaneous isolated PICA dissection presenting with lateral medullary infarction. Case Report: A 57-year-old female patient presented with right leg ataxia, headache, nausea and vomiting with a past medical history of hypertension. Neurological examination revealed right leg ataxia and left-side sensory change with right ptosis and miosis. The brain magnetic resonance imaging and magnetic resonance angiography showed an acute infarction in the right lateral medulla with abrupt luminal stenosis and subtle dilatation of the proximal segment of the right PICA. Transfemoral cerebral angiography showed an abrupt segmental stenosis of the right proximal PICA with a pre-stenotic fusiform dilatation, suggestive of dissection. The patient had a good clinical outcome with antiplatelet therapy. Conclusion: We report a rare case of spontaneous isolated PICA dissection with lateral medullary infarction. J Neurocrit Care 2014;7(2):137-140