One or several tests may be required to determine the nature and extent of a sleep disorder. Specially trained technologists and physicians who are specialists in sleep medicine administer and interpret the tests. During the test, measurements are recorded to identify sleep stages and sleep problems.
Tests offered at the Sleep Medicine Center include:
The nocturnal polysomnogram: a nighttime study that evaluates many physiologic aspects while sleeping. parameters include brain, eye and muscle activity and movements, breathing patterns, snoring quality and intensity, oxygen requirements, nocturnal seizures or abnormal sleep behaviors.
The nocturnal polysomnogram with treatment: a nighttime study similar to that described above but with an additional therapy such as positive airway pressure (CPAP or BI-PAP) or an oral/dental appliance.
The nocturnal split night polysomnogram: a combination of the above two polysomnograms used in cases where a severe and medically significant sleeping pattern is identified. In these cases, a person will be placed on some type of therapy after two to four hours of technical observation and documentation, after which, the study will resume for the remainder of the night.
The Multiple Sleep Latency Test (MSLT) or Maintenance of Wakefulness Test (MWT): daytime studies that evaluate the ability to resist staying awake or the urge to fall asleep
Pediatric sleep studies: similar to the nocturnal polysomnogram, but using equipment specially fitted for children. A parent spends the night with the child.
Common Sleep Disorders
There are multiple types of sleep disorders, and diagnosing them requires the expertise of the polysomnographic technologists who record and acquire the data and specially trained physicians who interpret the results. Common disorders include:
Insomnia: Characterized by difficulty falling asleep or staying asleep, insomnia is often caused by stress, depression, anxiety, caffeine, medications and chronic or occasional pain. Another common contributor is circadian rhythm disruption, such as jet lag or shift work.
Sleep apnea: Loud snoring accompanied by multiple, nightly brief episodes of breathing cessation suggests the presence of sleep apnea.
Periodic Limb Movement Disorder (PLMD): Symptoms occur during sleep, when the affected person’s legs will kick every 20 to 40 seconds throughout the night.
Restless Leg Syndrome (RLS): RLS is less common than PLMD. It is characterized by an uncomfortable sensation in the legs while lying down. Commonly described as a tickle or cramp, this feeling is relieved by movement and causes people to have to get out of bed to stop the sensation.
Advanced Sleep Phase Syndrome (ASPS) and Delayed Sleep Phase Syndrome (DSPS): Both are characterized by sleeping and waking at inconvenient times. A person with ASPS will wake earlier than his or her desired clock time. DSPS, on the other hand, results in going to sleep much later than one wishes.
Narcolepsy: This condition is marked by excessive drowsiness during the day, with a tendency to sleep at inappropriate times.
REM (Rapid Eye Movement) sleep behavior disorder: All body muscles (except those used in breathing or movement of the eyes) are normally paralyzed during REM sleep. In some people the paralysis is incomplete or absent and allows them to violently "act out" their dreams. Acting out of dreams can potentially lead to injury of the patient or bed partner.