Skip to main content
Dartmouth-Hitchcock logo
Summer Flowers In This Section

Evaluation and Testing

We offer comprehensive evaluation and sleep testing based on the referral from your physician.


After you have been referred to us, you will receive a packet of information and questionnaires in the mail along with some general insurance instructions. Once you receive the questionnaire packet, please call (603) 650-3630 to make a consultation appointment. Please complete the questionnaires and bring them with you to your consultation appointment.


Polysomnography (PSG)

Polysomnography is a safe and generally painless technique during which physiological functions of sleep are measured and recorded overnight. The recording technique is noninvasive (external) and all electrodes are applied on the skin surface.

When you arrive at the Sleep Disorders Center for your overnight evaluation, you will be greeted by one of our polysomnographic technologists and shown to your private room. Each of the rooms at the Sleep Disorders Center has a bedroom-like setting and is specially equipped to allow for the recording and assessment of sleep. Each of these bedrooms has a private bathroom with shower, TV with cable television, and a telephone. Our patient rooms each have a separate thermostat. All of our patient beds are Sleep Number beds so you may adjust the mattress firmness to your comfort level.

After you have settled into your room and changed into your sleeping attire, your technologist will explain the recording process while they are applying the various adhesive patches and sensors. During the overnight evaluation, we monitor a variety of sleep parameters, which may include:

  • Electroencephalogram (EEG) - Brain activity
  • Electrooculogram (EOG) - Eye movements
  • Chin Electromyogram (EMG) - Muscle tone in the chin
  • Leg Electromyogram (EMG) - Leg movements
  • Electrocardiogram (ECG) - Heart activity
  • Respiratory airflow and effort
  • Oximetry - Oxygen level within the blood
  • Continuous audiovisual recording

Once the setup process is complete, you should have time to relax, watch television or read before going to bed.

During the study, every attempt is made to allow for a comfortable night's sleep. Some people sleep differently away from home, but that does not usually affect the value of the sleep study. Your technologist will be stationed outside the bedroom all night to monitor the sleep recording and ensure your comfort.

In the morning, the technologist will wake you when your test is completed, usually between 6:00 and 6:30 am. If your test is scheduled for a Sunday through Thursday evening, the next morning between 9:00 and 11:00 am you will usually meet with one of our sleep physicians to discuss the results of your sleep study and treatment recommendations.

Depending on the results of your overnight sleep study, additional daytime testing may be necessary the following day. We perform two types of daytime testing called multiple sleep latency test (MSLT) and maintenance of wakefulness test (MWT).

Once the sleep data has been analyzed and interpreted by your sleep physician, a full written report including the summary of all the findings on the sleep study and treatment recommendations will be sent to your referring physician as well as to other physicians of your choosing. Your treatment and/or follow-up care will be coordinated between the sleep specialist and your physician.

Multiple sleep latency test (MSLT)

Multiple sleep latency tests, commonly called a "nap study," helps determine the severity of excessive sleepiness. This test is performed primarily during the day following your overnight sleep study.

During a nap opportunity, a person lies down in bed in a darkened room and allows him/herself to fall asleep. The individual is given 20 minutes to fall asleep and, if they do, they are given some additional time to continue sleeping. If the person does not fall asleep within 20 minutes, then the nap opportunity is ended. During the course of the day, this napping process is repeated approximately every 2 hours for a total of 4 to 5 napping opportunities. While the testing is taking place, one of our technologists will be stationed outside the room monitoring the sleep recording.

Maintenance of wakefulness test (MWT)

An alternative test to the MSLT is the maintenance of wakefulness test. The MWT helps to determine if a person is abnormally sleepy during the day by measuring the individual's ability to stay awake. This test is performed primarily during the day.

During a MWT session, an individual sits in a recliner chair in a darkened room with feet elevated, and attempts to stay awake for 20 minutes. During the course of the day, these sessions are repeated every 2 hours for a total of 4 sessions. While the testing is taking place, one of our technologists will be stationed outside the room monitoring the sleep recording.


Most sleep disorders can be treated or managed effectively once they are accurately diagnosed. Diagnosis and treatment recommendations for sleep disorders are based on the findings of the consultation including the overnight sleep recording.

Typically, for obstructive sleep apnea, one full night sleep evaluation is needed to assess an individual's sleep disorder. Then, if needed, the person returns for a second night for treatment such as CPAP.

Continuous positive airway pressure (CPAP)

Continuous positive airway pressure or CPAP, as it is commonly referred to, is a device that is used to help treat sleep disordered breathing such as obstructive sleep apnea.

CPAP is a highly effective treatment for obstructive sleep apnea. A person wears a light mask on their nose, which is attached to a CPAP machine. When the machine is turned on, a steady flow of air enters the sleeper's nose and flows into the airway. The air pressure from the machine then helps prevent snoring and obstructive sleep apnea from occurring by keeping the airway open while the person sleeps.

Contact Us