What is Polysomnography?
A sleep study is a diagnostic test that records your body’s activity as you are sleeping. It measures the function of multiple systems including brain, heart and respiratory system, helping your healthcare provider diagnose a range of sleep disorders. You may also hear it referred to as a polysomnogram, or “poly-som-no-gram.”
Nocturnal laboratory-based attended polysomnography (PSG) remains the gold standard in diagnosing obstructive sleep apnea syndrome and assessing various other sleep disorders such as narcolepsy, periodic limb movement disorder, insomnia, REM sleep behavior disorder, idiopathic hypersomnia and parasomnias. It is also used to evaluate the effectiveness of treatment for sleep apnea. In addition, PSG is a vital tool in evaluating a number of non-sleep-related medical conditions. 서울수면다원검사
The test is performed overnight while you are sleeping at a sleep center or hospital sleep lab. A credentialed technician monitors you in a private room, which is similar to a hotel room. You are typically asked to arrive in the evening and spend the night there while wires attach to your body that monitor a variety of physiologic parameters.
These include brain wave recordings called electroencephalography or EEG, eye movements and muscle activity called electrooculography or EOG, breathing patterns and effort, chest and abdominal wall movement (by piezoelectric sensors or respiratory inductance plethysmography), heart rate and rhythm, arm and leg movement, and blood oxygen levels.
A nocturnal PSG typically lasts about 8 to 10 hours. During this time you are alternating between periods of rapid eye movement (REM) sleep, when most dreaming occurs, and non-rapid eye movement (NREM) sleep. This cycle is repeated about every 90 minutes, and each period of NREM sleep alternates with a brief period of REM sleep.
During the sleep study you will be monitored with multiple sensors, which are plugged into a computer that interprets the data. The information gathered during the sleep study is evaluated first by the polysomnography technologist and then reviewed and interpreted by your health care provider.
If you are scheduled for a nocturnal PSG, it is important that you do not consume alcohol or caffeine before the test. Alcohol and caffeine are known to exacerbate obstructive sleep apnea, and they can alter the quality of your sleep. It is also a good idea to get into the habit of going to bed at the same time each night so that your results are comparable across nights. 연세로의료의원
While home apnea tests are growing in popularity, they are limited and do not provide the same level of information as a complete, attended PSG. Currently, there are few studies that can compare the results of a full-depth home apnea device to those of an in-lab PSG.
In the future, these home apnea tests may become more accurate and affordable as the technology improves. Until then, you should continue to schedule an in-lab, Type I, polysomnography test.