Variants of Avellis Syndrome Due to Medulla Oblongata Infarction: A Case Series.

INTRODUCTION: Avellis syndrome is classically defined as a neurological disorder characterized by paralysis of the soft palate and vocal cords on one side, and a loss of sensation of pain and temperature sense on the other side. Between 2010 and 2020, 5400 patients with ischemic stroke were admitted to the Stroke Unit and prospectively entered in our Stroke Registry.

CASE REPORT: A total of 216 patients with magnetic resonance imaging-proven ischemic lesions restricted to the medulla oblongata were identified. Among them, 5 patients had Avellis syndrome with a small medullary infarction. There was paralysis of the soft palate and vocal cords in all patients, but besides of loss of pain sensation and temperature sense, there were also partial disturbances in position and vibration senses in 3 patients. Different types of neuro-ophthalmologic findings were observed in 4 patients. In 5 patients, the cause of medulla oblongata infarct was microscopic polyangiitis vasculitis, neuro-Behçet disease, vertebral artery dissection, small vessel disease, and neurobrucellosis small vessel vasculitis.

CONCLUSIONS: Avellis syndrome may present with additional neurological findings besides its classic definition. Apart from atherosclerotic disease, rare causes should be investigated in detail in small ischemic medullary lesions.