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8095 Innovation Park Drive, Fairfax, VA 22031


Sleep Disorders Program: Sleep Study Information


Are you considering getting a sleep study done? Below are some frequently asked questions (FAQ) people commonly have before visiting a sleep lab.

What Is a Sleep Study?

The stages of sleep range from light to deep. Each stage has characteristics that can be measured. A sleep study is a number of tests done at the same time during sleep. The tests measure specific sleep characteristics and help to diagnose sleep disorders. A sleep study may also be called polysomnogram.

The basic recordings done during a sleep study may include:

  • Electroencephalography (EEG). This measures brain wave activity.
  • Electrooculogram (EOG). This measures eye movement.
  • Electromyography (EMG). This measures muscle movement.
  • Other recordings. An electrocardiogram (ECG) may be used to record electrical activity of the heart. Video recordings may also be made of you while you sleep.

In addition, these tests may be done:

  • Multiple sleep latency tests (MSLT) measure how long it takes to fall asleep
  • Multiple wake tests (MWT) measure whether you can stay awake during specified times.

Doctors trained in sleep medicine evaluate test results to treat sleep issues. A trained sleep technician will be with you in the sleep lab during the testing period.

When Should I Visit a Sleep Center?

Consider a sleep study if you have had trouble sleeping for more than a month or if you are tired during the day for unknown reasons. If you have trouble falling asleep or staying asleep, it is important to have the cause evaluated in a sleep lab.

What Is Measured During a Sleep Study?

Sleep studies generally take place in a sleep lab during your normal sleeping hours. The goal is to record brain and body activity that happens during sleep so that sleep disorders can be diagnosed and treated.

During a sleep study, the following may be measured:

  • Eye movement. The number of eye movements and their frequency or speed.
  • Brain activity. The electrical currents of the brain.
  • Limb movement. The number and intensity of movements.
  • Breathing patterns. The number and depth of respirations.
  • Heart rhythm. The electrical activity of the heart.
  • Oxygen saturation. The percentage of oxygen in the blood.
  • Acid/base balance of the stomach. The amount of acid secreted during sleep.
  • Sleep latency. The time it takes to fall asleep.
  • Sleep duration. The period of time a person stays asleep.
  • Sleep efficiency. The ratio of the total time asleep to the total time in bed.

What Happens During a Sleep Study?

A sleep study is a noninvasive, painless evaluation of your sleep. Electrodes monitor your brain waves, rapid eye movements, breathing patterns, respiratory efforts, oxygen levels, snoring, muscle tone and leg movements, electrocardiogram and heart rate.

Are Sleep Studies Covered by Insurance?

Yes. Most private health insurance companies and Medicare cover office visits, sleep studies and CPAP services.

Do I Need a Referral?

You do not need a referral if you have Medicare or a PPO. HMOs usually require a referral. You can generally call your doctor and ask him or her to fax the referral.

What Are the Consequences of Not Treating Sleep Disorders?

Sleep disorders can contribute to daytime sleepiness, fatigue, cognitive impairment and poor job performance. More serious consequences of sleep disorders include hypertension, cardiac disease, stroke, anxiety, depression, memory loss and dementia.

What If I Can't Fall Asleep During the Study?

Nearly everyone is able to fall asleep. It just may take you a little longer than normal.

Can I Get up to Go to the Bathroom During the Study?

Yes. The electrodes are collected together to a central attachment that easily detaches to free you to get up and out of bed.

Can I Take My Sleep Study During the Day?

We can accommodate patients with any sleep pattern, including those who don't usually sleep at night because of working a late shift. We can also work with people who just prefer going to bed very late or very early. 

How Long Do I Have to Be at the Sleep Lab?

Arrival times are flexible. Typically patients arrive between 8 – 10 p.m. Patients are usually with us about 9 hours. We aim to get at least 7 hours of sleep study time.

What Should I Bring with Me?

Pack as though you are going to a hotel. We furnish basic toiletries such as soap, shampoo and toothpaste.