Case of a non-24 h sleep-wake syndrome patient improved by phototherapy.

Polysomnography (PSG) and body temperature were examined in a patient with non-24 h sleep-wake syndrome who responded to phototherapy. The patient was a 17-year-old male who had been suffering from a free-running sleep-wake rhythm for 2 months. Phototherapy was administered to the patient while he was admitted to our hospital. This treatment immediately changed the free-running sleep-wake and body temperature rhythm of the patient to the environmental 24-h rhythm. On a polysomnography, total sleep time and stages 1 and 2 and REM sleep were decreased, and percentage stage 3+4 was increased by phototherapy. The time of minimum body temperature (mBT) was located at the latter half of the sleep phase through the clinical course of the patient.