Sleep Health Center

Terminology for Sleep Study Order Form

Baseline and PAP, no MSLT- At beginning of sleep study an observation period lasting approximately 2 hours to determine need for treatment therapy (CPAP, BIPAP)

PSG - Polysomnography - the overnight test performed at the Sleep Health Center to rule out Obstructive Sleep Apnea and other sleep disorders.

CPAP, PAP, BIPAP - positive airway pressure. A device that delivers pressure to the upper airway via a mask to prevent upper airway collapse. It can deliver pressure at one setting (Continuous), or at a dual setting (BIPAP), depending upon patient need and comfort level.

MSLT - Multiple Sleep Latency Testing - this is a separate test that follows an overnight study. The patient is allowed to nap briefly every 1 ½ to 3 hours, in an attempt to determine the patient's level of sleepiness at various times during the day. Used to diagnose Narcolepsy and Excessive Daytime Sleepiness.

MWT - Maintenance of Wakefulness Test - this test is performed the day following a patient's normal nights sleep. A series of 40 minute sessions where the patient is placed in a comfortable, dark, test room and asked to stay awake for the entire 40 minutes, in a sleep-inducing environment. Frequently used by the DOT and FAA to evaluate sleepiness in drivers and pilots.

Scalenes, Sternocleidomastoid EMG - specific sites where EMG (Electromyogram) electrodes are placed to measure respiratory muscle effort during a sleep study.

Transcutaneous CO2 - measurement of carbon dioxide (CO2) levels in the patient's body. A heated electrode is attached to the patient's skin, and a trend of CO2 levels is obtained throughout the night.

Seizure Montage - this is a recording of sleep with additional EEG electrodes placed on the patient's scalp, looking for possible seizure activity during sleep.

4 Limb EEG - in addition to the limb movement electrodes routinely place on the patient's legs during a sleep study, additional leads are placed on the arms to further evaluate movement disorders of sleep.

Audio Stimulus in NREM Sleep - this is when the recording technologist disturbs a patient's sleep in an attempt to stimulate unusual behaviors that the patient may have discussed as a concern to their physician.