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Overlake Sleep Disorders Center (OSDC) is a full-service sleep center providing a highly experienced team of physicians and technicians specializing in sleep medicine. OSDC is proud to offer an accredited on-site sleep laboratory and a DME store for our patients’ “one-stop-shop” convenience.

Many laypersons are unaware of the health hazards and hidden dangers that sleep disorders wreak on the body if left untreated. Listed below are common tests and services we use to evaluate and treat sleep disorders.

PSG (Polysomnography)

A polysomnography (PSG) is a test that doctors use to evaluate a patient’s sleep patterns and diagnose sleep disorders. Also known as a ‘sleep study’, PSG measures vital signs, brain waves, and body movements while you sleep. Doctors often recommend polysomnography to patients who show signs of sleep apnea, restless legs syndrome, narcolepsy, sleep walking, or insomnia.

After an evaluation by one of our physicians, if you are determined to need a sleep study, you’ll be scheduled to come back to our office for a PSG test to spend the night in our comfortable, hotel-like sleep lab, which consists of private rooms, each with its own private bathroom. Each room is designed with your comfort in mind including remote-controlled cable TV, comfortable beds and pillows, and a home-like appearance–all to help you fall asleep easier. Sensors will be placed on your body with wires long enough to facilitate comfortable sleep positions and movement. Sleep technologists will watch you, listen to you, and monitor your biological activity during your sleep. After the study is over, your doctor will use this information to make a diagnosis and develop a recommendation for treatment if necessary.

CPAP Titration

CPAP titration is a sleep study often necessary prior to prescribing a continuous positive airway pressure mask to patients with sleep apnea. This test is necessary to determine the amount of air pressure necessary to maintain open airways during sleep. During CPAP titration, you sleep in a sleep lab wearing a CPAP mask while technicians monitor your oxygen levels, snoring, and whether your airways are staying open. CPAP titration may be performed during the second half of a PSG test, or it may be administered on a separate night.

Multiple Sleep Latency Testing (MSLT)

MSLT, or Multiple Sleep Latency Testing, is a sleep study used to determine the amount of time it takes a person to fall asleep. It is often performed after undergoing a PSG. During an MSLT, you will enter the sleep lab to take 20-minute naps at 2-hour intervals throughout the day. A technician monitors your vital signs, movements, and REM sleep during the nap. Doctors often use MSLT to confirm a diagnosis of excessive daytime sleepiness, such as in narcolepsy or idiopathic hypersomnia.

Maintenance of Wakefulness Test (MWT)

MWT is the Maintenance of Wakefulness Test, which is used to determine how easily a patient stays awake in a sleep-inducing environment. Patients sit in a dark, non-stimulating room with no light source other than a nightlight. The goal is to stay in the room still for a specific period of time without falling asleep. This process is repeated a few times throughout the day to help doctors determine a patient’s level of daytime sleepiness.

Home (Portable) Sleep Test (HST/ OCST)

An HST, or Home Sleep Test, also termed an “Out of Center Sleep Test” is a PSG performed from the comfort of a patient’s home for the purpose of confirming a diagnosis of obstructive sleep apnea. Doctors may use HST because it is more comfortable and convenient for the patient or if your insurance plan dictates that an HST precede an on-site lab sleep study. If you undergo an HST, you will receive equipment from your doctor that monitors vital signs, breathing, and blood oxygen levels during sleep. This information will be provided to your doctor, who will use the data to make a diagnosis or request additional screening.

Dental Sleep Medicine

Dental sleep medicine is used to manage abnormal breathing patterns during sleep. Disorders like frequent snoring or obstructive sleep apnea are treated using oral appliances designed to keep the airways open and prevent muscle relaxation during sleep. Dental sleep medicine devices are worn like a retainer or mouth guard during sleep only and work by immobilizing the tongue or holding the jaw forward. Dental oral appliances can work in cases where CPAP therapy has failed.

Durable Medical Equipment

Treating sleep disorders requires the use of Durable Medical Equipment (DME). Many insurance plans have strict guidelines surrounding the need to authorize the use of such equipment and supplies.

At OSDC, we want you to know that you always have freedom of choice in selecting your DME provider. We are proud to have this service available as a convenience to our patients. Our therapists have the breadth of knowledge and experience to train and fit our patients with the proper equipment and supplies. For more details about DME, please click on the “DME Orders” page.