Polysomnography is a sleep study. This test records certain body functions as you sleep, or try to sleep. Polysomnography is used to diagnose sleep disorders.
Sleep study; Polysomnogram; Rapid eye movement studies; Split night polysomnography; PSG; OSA - sleep study; Obstructive sleep apnea - sleep study; Sleep apnea - sleep study
How the Test is Performed
There are two stages of sleep:
REM sleep alternates with NREM sleep about every 90 minutes. A person with normal sleep most often has four to five cycles of REM and NREM sleep during a night.
A sleep study measures your sleep cycles and stages by recording:
Polysomnography can be done either at a sleep center or in your home.
AT A SLEEP CENTER
Full sleep studies are most often done at a special sleep center.
You may be able to use a sleep study device in your home instead of at a sleep center to help diagnose sleep apnea. You either pick up the device at a sleep center or a trained therapist comes to your home to set it up.
Home testing may be used when:
How to Prepare for the Test
Whether the test is at a sleep study center or at home, you prepare the same way. Unless directed to do so by your doctor, do not take any sleep medicine and do not drink alcohol or caffeinated beverages before the test. They can interfere with your sleep.
Why the Test is Performed
Polysomnography can also diagnose other sleep disorders:
A sleep study tracks:
Most people have short periods during sleep where their breathing stops or is partly blocked. The Apnea-Hypopnea Index (AHI) is the number of apnea or hypopnea measured during a sleep study. AHI results are used to diagnose obstructive sleep apnea.
Normal test result show:
What Abnormal Results Mean
In adults, test results above 5 may mean you have sleep apnea:
To make a diagnosis and decide on treatment, the sleep specialist must also look at:
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Review Date: 1/15/2018
Reviewed By: Allen J. Blaivas, DO, Division of Pulmonary, Critical Care, and Sleep Medicine, VA New Jersey Health Care System, Clinical Assistant Professor, Rutgers New Jersey Medical School, East Orange, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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