Sleep Studies
Overnight Sleep Studies
An essential part of a sleep assessment is an overnight sleep study.
An overnight sleep study, or polysomnogram, entails sleeping overnight in a laboratory bedroom with specialized equipment designed to monitor brain waves, eye movements, respiration, heart rate and rhythm, and leg movements. All patients are monitored by a qualified sleep technician on duty.
An overnight sleep study is useful for characterizing an individual's sleep, including its duration and quality, and is also necessary to diagnose certain sleep coniditons such as sleep apnea.
Our facility contains three bedrooms for conducting such studies. Our bedrooms have accomodations to allow a parent or guardian to accompany a child being studied, two of the rooms containing two beds for this purpose, and the third containg a double bed for those who wish to co-sleep with their child.
Daytime Studies
Daytime studies are also conducted by our centre on selected patients.
The Multiple Sleep Latency Test (MSLT) consists of four to five 20-minute nap opportunities every 2 hours during the day. The test measures the severity of sleepiness as well as the presence of REM sleep episodes.
The Maintenance of Wakefulness Test (MWT) consists of four sessions, 2 hours apart, whereby patients are seated in a dark room and asked to remain awake for twenty minutes. The test is a measure of alertness.
Dim Light Melatonin Onset Assay (DLMO)
The Dim Light Melatonin Onset consists of taking saliva samples every hour in a darkened room beginning in the early evening and ending in the early morning. The samples are analysed with respect to melatonin levels and the study as a whole determines when melatonin is being secreted by the brain. Melatonin levels normally rise in the early evening, but in individuals with Circadian Rhythm Disorders melatonin secretion may be impaired. The DLMO is useful in the diagnosis of such conditions.
More information on sleep study procedures may be found in our brochure Sleep Center Procedures.
