A previously healthy 60-year-old man presented with a sudden inability to stand; whenever he tried, he would fall to his left. He noted no other symptoms, in particular, no vertigo, diplopia, dysarthria, paresthesia, numbness, weakness, or incoordination. On examination the sole abnormality found was that whenever he tried to stand, he would lean to the left and would fall unless supported (Figure 1). He was able to sit straight. Dilated fundus indirect ophthalmoscopy showed a disconjugate, counterclockwise (from the patient's point of view) offset of torsional eye position (Figure 2). Settings of the subjective visual horizontal were offset to the left by 21° in the left eye and by 28° in the right eye. Magnetic resonance imaging results on the day of the event were normal but 2 days later showed a small infarct in the left lateral medulla (Figure 3). The patient spent 4 days in the hospital and a month later could stand normally.
Akdal G, Thurtell MJ, Halmagyi GM. Isolated Lateropulsion in Acute Lateral Medullary Infarction. Arch Neurol. 2007;64(10):1542-1543. doi:10.1001/archneur.64.10.1542