Types of Sleep Studies

Our office performs four major types of sleep studies. PSG, PSG with CPAP MSLT, MWT and Split Night Studies. The following list is adapted from the www.nhlbi.nih.gov.

Polysomnogram

A PSG is a non-evasive study that records brain activity, eye movements, heart rate, and blood pressure. It also records the amount of oxygen in your blood, how much air is moving through your nose while you breathe, and chest movements that show whether you're making an effort to breathe. In some cases, breathing sounds, including snoring, also are recorded.

PSG results are used to help diagnose:

Titration Study

CPAP is the most common treatment for sleep apnea. A CPAP machine uses a small pump to gently supply air to your nose or mouth through a special mask. The right setting involves adding just enough extra air to create mild pressure that keeps your airways open while you sleep.

If the PSG shows signs that you have sleep apnea, you will use a CPAP machine during the second half of the split-night study. A technician checks your breathing using the PSG and adjusts the flow of air through the CPAP mask to find the correct setting for you.

A PSG also helps doctors:

Multiple Sleep Latency Test

This sleep study measures how sleepy you are at different times of the day. It's typically done the day after a PSG. You relax nap in a dark room. The MSLT records whether you fall asleep during the test and what types and stages of sleep you're having. Sleep has two basic types: rapid eye movement (REM) and non-REM. REM sleep and non-REM sleep occur in patterns throughout the night.

The test is repeated three or four times throughout the day. This is because your ability to fall asleep also changes throughout the day.

Maintenance of Wakefulness Test The Maintenance of Wakefulness Test (MWT) is used to measure how alert you are during the day. It shows whether or not you are able to stay awake for a defined period of time. This is an indicator of how well you are able to function and remain alert in quiet times of inactivity.

The test is based on the idea that your ability to stay awake may be more important to know in some cases than how fast you fall asleep. This is the case when the MWT is used to see how well a sleep disorders patient is able to stay awake after starting treatment. It is also used to help judge whether a patient is too tired to drive or perform other daily tasks.

The test isolates you from outside factors that can influence your ability to fall asleep. These factors include such things as the following: