Sleep testing is how many sleep disorders are diagnosed. Many patients have already undergone testing and bringing the results of these tests can potentially obviate the need to repeat them.
Polysomnography or PSG has historically been the gold standard for the diagnosis of sleep apnea, restless leg syndrome and a number of other sleep disorders. It consists of at least one overnight stay in the sleep lab. Muscle, eye, brain, heart, respiratory activity and oxygen levels are monitored through the night. An initial PSG is diagnostic meaning it makes the diagnosis of a sleep disorder. A subsequent PSGs may be used to establish or optimize a particular treatment, typically CPAP or BiPAP and is referred to as a split night or titration study.
Home sleep study
Recently a modified portable sleep study was approved in the diagnosis of obstruction sleep apnea at home. This machine is set up in your home and measures heart rate, oxygen levels, respiratory effort and airflow while you sleep in your own bed. It is generally picked up at a sleep lab or mailed to you directly and used for 1-3 nights. It is important to know that this is not appropriate for everyone and is ordered at the discretion of the sleep physician.
Multiple sleep latency test
A multiple sleep latency test or MSLT is used in the diagnosis of narcolepsy. It is performed during the daytime, sometimes following an overnight polysomnography, and consists of measuring the time to fall asleep (sleep latency) during 4-5 20 minute nap periods spread out by 2 hours. The set up is essentially the same as a PSG with leads measuring heart, brain, eye and muscle activity.