Multiple Sleep Latency Test

The Multiple Sleep Latency Test (MSLT) is a sleep disorder diagnostic tool that tests for excessive daytime sleepiness that is often used to diagnose narcolepsy and idiopathic hypersomnia.

Prior to the Multiple Sleep Latency Test (MSLT) a patient will undergo an all-night Polysomnogram (PSG). The patient will remain in the Sleep Lab the following day and can expect to remain there until approximately 3:00-4:00pm.

The MSLT is a full-day test consisting of four-five naps scheduled two hours apart. During each nap trial, the patient will attempt to sleep and the time it takes to fall asleep will be recorded. Tests will be conducted within one of our Sleep Lab’s private rooms to ensure elimination of outside factors.

Sensors placed on the head, face and chin will allow for a sleep technologist to determine when the patient is asleep or awake and collects data used to determine REM sleep cycles. Patients with narcolepsy often have two or more REM during the MSLT while patients with idiopathic hypersomnia typically fall asleep easily but do not reach REM sleep.