Multiple Sleep Latency Test (MSLT) is also called a nap study. It is performed for people with excessive daytime sleepiness.
The MSLT can identify narcolepsy, idiopathic hypersomnia (excessive sleepiness without a cause) or whether a normal amount of daytime sleepiness is present.
PROCEDURE :
It is performed during daytime.
Typically this study is done after an initial overnight polysomnogram (PSG) study.
After waking up, a person will have scheduled naps at 2 hour intervals during the day.
Generally, they are asked to lie in bed for 20 minutes with the goal of falling asleep. A technician will monitor for the onset of sleep , in particular, REM sleep. After 20 minutes, they will be awakened or told that the time for a nap has ended. Then, at two-hour intervals, this process is repeated 4 or 5 times. Typically this will take 8 to 10 hours.