Sleep Disorder Testing and Diagnosis

The Center for Sleep Medicine at NewYork-Presbyterian/Weill Cornell Medical Center uses the most advanced technology and tools to understand and diagnose sleep disorders.

Available tests include the gold-standard overnight sleep study (polysomnography), home sleep studies, nocturnal oximetry at home and actigraphy.

Each patient is evaluated with the most effective test for diagnosing their specific disorder and optimizing their treatment plan.

Overnight Sleep Study

The overnight sleep study, also called polysomnography (PSG), is a comprehensive test performed in the Center to diagnose sleep disorders and assess the effectiveness of treatment.

After arriving at the Center for Sleep Medicine, patients are greeted by trained and certified sleep technologists and set-up with the monitoring equipment. An important goal is to have patients ready to go to sleep close to their regular bedtime as comfortably as possible with the monitoring equipment. The facility's private monitoring rooms are designed for the patients' comfort and include their own thermostat and a private bathroom.

The specialists at the Center for Sleep Medicine will tailor the study request to each patient's specific symptoms, condition, and needs. Additional tests may be required, such as:

  • Daytime sleep monitoring
  • Capnography
  • Treatment trial with a positive airway pressure (PAP) device, including:
    • Continuous positive airway pressure (CPAP)
    • Bi-level positive airway pressure (BIPAP)
    • Adaptive Servo-Ventilation (ASV)
    • Average Volume Assured Pressure Support (AVAPS)

Instructions for an Overnight Sleep Study (PDF)

Positive Airway Pressure (PAP) Nap

This study is available for patients who experience difficulty in adjusting to a PAP device. During a PAP Nap evaluation, patients meet with a specialized technician and are allowed to take a nap of two or more hours with the most comfortable mask interface, receiving guidance from the center's specialists to help them adapt and adjust to treatment.

Daytime Sleep Study

The degree of drowsiness and/or wakefulness during the day can be assessed using specific daytime tests, such as the multiple sleep latency test (MSLT) or maintenance of wakefulness test (MWT).

  • The MSLT consists of a series of naps taken throughout the day and provides an objective assessment of daytime sleepiness. It is completed during the day following an overnight sleep study. This test can requires a stay in the Center.

  • The MWT is a similar test, performed in the Center during the day following an overnight sleep study. It measures the person's ability to stay awake during conditions that are prone to sleep.

Instructions for Daytime Testing (PDF)

Home Sleep Study

In some cases, a home sleep study may be useful for evaluating sleep apnea. Breathing during sleep is monitored using a portable device. This study does not monitor sleep and is especially useful for patients who prefer to be tested in their own homes and in cases where no other sleep disorder, besides sleep apnea, is of concern.

To prepare for the study, patients first meet with a sleep technologist to obtain instructions on how to connect the portable device. During that night, in their home, they attach the device as instructed and sleep according to their normal routine. Patients then return the equipment the following day; the data is downloaded and interpreted by one of Weill Cornell Medicine's board-certified Sleep specialists.

Instructions for a Home Sleep Study (PDF)

Nocturnal Oximetry

Patients with sleep apnea or other respiratory problems may experience reduced blood oxygen levels during sleep. The nocturnal oximetry test measures oxygen levels during the night and may be used to guarantee effective treatment for sleep apnea and other cardiorespiratory problems during sleep.

This test is part of the overnight sleep study and home sleep study. In some cases, a portable device for oximetry-only recording are used.

Actigraphy

This test records activity and movement during the night and uses proprietary algorithms to distinguish sleep from wakefulness. Over the course of one to two weeks, patients wear a small monitor (similar to a wristwatch) throughout the day and night. The device gathers information about patients' sleep patterns and analyzes the data, which may be used to help guide the evaluation and treatment.