Full Polysomnography Test
Level 1 Sleep study (Polysomnography) is an evaluation performed as part of a sleep study. Polysomnography is a painless and safe sleep test. It usually takes place in a hospital or private clinic lab. An at-home sleep test is considered a Level 3 sleep study, or cardiorespiratory sleep polygraph.
If you have already been prescribed an in-lab polysomnography by your doctor, contact us to find out more about this test and to schedule an appointment.
Why do a polysomnography test?
This sleep test can identify different parameters such as:
- respiratory arrests (sleep apnea)
- hypopneas that cause oxygen deprivation or short brain awakenings
- high resistance of the upper airways
Polysomnography can also identify other sleep disorders such as:
- narcolepsy
- restless legs syndrome
- excessive snoring
- insomnia
How is a polysomnography test performed?
Polysomnography evaluation is most often performed at night. The patient is placed in a room so that they can be monitored during their sleep phases.
Electrodes are placed on the patient’s head, face, torso, legs and arms.
During the test, the respiratory therapist will monitor many body functions including:
- Brain waves (EEG)
- Eye movements (EOG)
- Chin muscle tone (CEMG)
- Breathing patterns
- Snoring or any other noise emitted during sleep
- Heart rate and blood pressure
- Blood oxygen levels
- Body position
Muscle activity or skeletal muscle activation (EMG). Frequent leg movements could be an indication of periodic limb movement disorder.
You should not to consume alcohol or coffee for at least 24 hours before the sleep test.
Polysomnography test results
A single polysomnography is sufficient to assess the patient’s sleep and detect any underlying sleep disorders.
Polysomnography measures :
- Different sleep cycles
- muscle movements
- Frequency of apneas during the night
- Frequency of hypopnea
Sleep specialists use polysomnography to determine an index of sleep apnea or hypopnea measured during the sleep cycle. An index equal to 5 or less is considered normal.
If the score is greater than 5, the patient is identified as having sleep apnea:
- between 5 and 15, sleep apnea is considered mild.
- between 15 and 30, sleep apnea is considered moderate.
- greater than 30, sleep apnea is considered severe.
What to do after a polysomnography test?
The sleep test data will be analyzed and interpreted by the clinical team. The results will be sent to your doctor or the Dorma specialist who prescribed the sleep study.
Depending on the results, we will offer you a second appointment to discuss any relevant treatment options together.
What are the alternatives to a polysomnography test?
Full polysomnography tests are not required for everyone. Alternatives include a home respiratory polygraphy, or level 3 sleep test. The respiratory polygraphy is basic compared to the polysomnography, but affords you the comfort of performing the test at home.
Ask your doctor or book an appointment now to learn more about the various alternatives to polysomnography.