[A case of a syndrome resembling PSP after aortic arch replacement under deep hypothermic circulatory arrest]

A 57-year-old man presented with acute signs and symptoms mimicking PSP (bradykinesia, supranuclear ocular palsy, dysphagia, neck dystonia, and apraxic gait) on the day after a graft replacement surgery, which was performed for aortic arch aneurysm under deep hypothermic circulatory arrest (rectal temperature, 18 degrees C). Dysphagia improved temporarily, but relapsed after a few months. Symptoms did not change during 2 years of antiparkinsonian drug administration. Brain images obtained before the surgery revealed slight atrophy of the midbrain tegmentum and frontal lobes, but the patient was asymptomatic. No findings of cerebral vascular disease and hypoxic encephalopathy were observed on brain images after the surgery. These clinical features resembling PSP might have been caused by deep hypothermia and the patient's predisposition for PSP. This is the first case report in Japan of a syndrome resembling PSP that occurred after aortic arch replacement under deep hypothermic circulatory arrest.