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Sleep Medicine and Research Center

Sleep Disorder Diagnosis

Some sleep disorders can be diagnosed by a sleep specialist after collecting a detailed medical history, sleep questionnaires and sleep logs. Others require diagnostic testing to confirm or rule out certain disorders.

The most common diagnostic test used by the Center is a sleep study. Daytime Multiple Sleep Latency Test (MSLT)/Maintenance of Wakefulness Test (MWT) sleep studies are also conducted when appropriate. When a circadian rhythm or shift work sleep disorder is suspected, actigraphy may be ordered. Some sleep disorders can even be diagnosed with simple lab work. Based on your symptoms, your sleep specialist will determine the most appropriate tests.

Sleep Study
A sleep study, also called a polysomnogram, is a painless procedure that allows sleep professionals to collect data critical to diagnosing common sleep disorders. Your sleep study will be monitored by registered technologists to ensure the highest-quality data possible is captured. These technologists will also make observations and assist you as needed.

After you change into pajamas, the technologists will apply approximately 24 sensors and electrodes, used to monitor brain activity, eye movements, leg movements, muscle tone, breathing, oxygen saturations and snoring. The technologists will make a recording of the sleep study for your sleep physician to review.

It may be possible to diagnose and begin treating sleep apnea in a single night. If a sleep apnea diagnosis can be established after several hours of data are collected, a CPAP (continuous positive airway pressure) titration may be initiated. The technologist will enter the room to fit you with a CPAP mask and help you adjust to the mask. The technologist will slowly increase the CPAP settings until signs of breathing problems and snoring are eliminated. The final determination of your diagnosis and CPAP pressure will be made by a board-certified sleep physician after he or she personally reviews your sleep study.

When adequate data is collected, the sleep study will conclude. The technologist will remove all the wires and sensors. You will be offered a light breakfast and given the opportunity to shower before leaving the sleep center. Towels, most toiletries and a hair dryer are available.

Sometimes patients need a caregiver or family member to stay at the sleep center overnight to assist with medication administration, mobility limitations or specific medical or cognitive needs. If this is the case for you, your sleep physician will assess your needs and make appropriate recommendations and arrangements for the night of the sleep study.

Each bedroom has independent temperature control, a full-size bed and a private bathroom.

Sleep Study Results, Recommendations and Follow-up
Upon completion of the sleep study, a board-certified physician will review all data. A registered technologist will score the study and present finalized results to your physician for interpretation.

If you aren't started on CPAP, you will probably return to the Sleep Medicine and Research Center to receive your sleep study results from your sleep physician. Recommendations and a treatment plan will be discussed at this time.

If you are started on CPAP therapy during the sleep study, you will have home setup arranged through a durable medical equipment company within approximately seven days. You will also be asked to return to the sleep center for a follow-up office visit within four to six weeks. You will meet with a registered nurse and your sleep physician to discuss adjustment and tolerance to CPAP and to ensure adequate symptom improvement. All results will be shared with your primary and referring doctors, as directed by you.

Multiple Sleep Latency Test/Maintenance of Wakefulness Test
Certain sleep disorders may require daytime testing following the overnight sleep study. Your sleep physician may recommend a Multiple Sleep Latency Test (MSLT) or a Maintenance of Wakefulness Test (MWT) to measure daytime sleepiness.

What is an MSLT? The MSLT is a nap study that consists of four or five nap opportunities throughout the day. The test is used to see how quickly you fall asleep in quiet situations during the day. The MSLT is the standard way to accurately assess your level of daytime sleepiness.

What is an MWT? The MWT is designed to test your ability to stay awake when all stimulation has been removed.

MSLT/MWT testing may last eight to 10 hours; however, the actual end of testing is determined by a sleep physician. Testing will occur approximately every two hours, and the length of each test will vary. Your study will be conducted by a sleep technologist. On the day of your test, your sleep technologist will further explain what you should expect. Because of the uniqueness of this particular type of testing, it is highly recommended that your entire day/early evening be completely free of outside obligations. 

Prior to your MSLT or MWT:

  • A urine specimen will be collected.
  • Some of the electrodes used during the night will be removed.
  • You will be encouraged to change into comfortable street clothes.
  • Breakfast will be served.

During Non-testing Periods, You Are Required To:

  • Remain out of bed and remain awake between naps.
  • Abstain from any form of caffeine, including chocolate.
  • Refrain from smoking per St. Luke's Smoking Policy.
  • Avoid engaging in vigorous exercise.

During Your Free Time, You May Wish To:

  • Read books or magazines.
  • Work on paperwork.
  • Watch movies or TV (a VCR/DVD player is available).
  • Use your laptop (Wi-Fi is currently unavailable).
  • Use the telephone (cell phone must be turned off during testing).
  • Work on crafts.

Your sleep physician may request that you wear an actigraph. A sleep actigraph is a small device worn on the non-dominant arm and is usually shaped like a wristwatch. It is used to monitor movement and activity and can collect and store data for several weeks. Actigraphy can provide an estimate of sleep patterns in patients suspected of certain sleep disorders, as well as measure the effectiveness of prescribed treatments.

Sleep Disorder Information
Sleep Disorder Treatment Options