Current status of polysomnography in Japan

Abstract

Polysomnography (PSG) records simultaneously many physiological signals throughout a given night, including electroencephalograms, electro-oculograms, electromyograms, nasal-oral flow, chest and abdominal movements, electrocardiograms and arterial oxygen saturation. PSG evaluates sleep state and wakefulness, and both quality and quantity of sleep. It is also useful for diagnosing sleep breathing disorders, periodic limb movement disorders, sleep-related epilepsy, narcolepsy, and rapid eye movement sleep behavior disorders and their severities. To maximize the advantages of PSG, it should be performed by a trained technologist in a sleep laboratory equipped with a monitoring camera and a microphone to record both images and sound. Unfortunately, the number of such sleep laboratories is limited in Japan because of the high equipment and labor costs and difficulties in the education and training of technologists. Since a PSG report directly contributes to the diagnosis of various sleep disorders, technologists have a heavy responsibility. It is necessary for the technologists to perform PSG appropriately and safely in order to obtain an accurate score. In this report, I will describe the standard procedure and scoring method from a technical viewpoint and the current position and status of PSG in Japan.