IMPORTANT NOTICE: At Fortis Healthcare, we are fully supportive of the National priorities set out by the Hon’ble Prime Minister of India. Further to the directives of the Government provided in their press release dated 8th Nov 2016, payments at Government hospitals can be made through 500 and 1000 Rupee denomination notes. In view of the hardship being caused to the large number of patients at private hospitals, we have made an urgent representation to the Government that this exemption should apply equally, for payments, at private hospitals. We are following up with the authorities and hope the Government will step in quickly to resolve this anomaly. Meanwhile, at Fortis hospitals across the country, we continue to accept payments through credit card, debit card and electronic banking transfers. As 500 and 1000 Rupee denomination notes are no longer legal tender we are only accepting 100 Rs and lower currency notes. As per Government regulation, a PAN card and legitimate ID proof is however required for payments in cash exceeding Rs 50,000. Meanwhile we continue to ensure that emergency cases get immediate medical attention without delay whatsoever and have put in more administrative staff and help desks to assist patients.

Polysomnography (sleep study)

Polysomnography, also called a sleep study, is a test used to diagnose sleep disorders. Polysomnography records your brain waves, the oxygen level in your blood, heart rate and breathing, as well as eye and leg movements during the study.

Polysomnography usually is done at a sleep disorders unit within a hospital or at a sleep center. You'll be asked to come to the sleep center in the evening for polysomnography so that the test can record your nighttime sleep patterns. Polysomnography is occasionally done during the day to accommodate shift workers who habitually sleep during the day.

In addition to helping diagnose sleep disorders, polysomnography may be used to help adjust your treatment plan if you've already been diagnosed with a sleep disorder.


Why it's done Risks How you prepare What you can expect Results

Polysomnography monitors your sleep stages and cycles to identify if or when your sleep patterns are disrupted and why.

The normal process of falling asleep begins with a sleep stage called non-rapid eye movement (NREM) sleep. During this stage, your brain waves, as recorded by electroencephalography (EEG), slow down considerably.

Your eyes don't move back and forth rapidly during NREM, in contrast to later stages of sleep. After an hour or two of NREM sleep, your brain activity picks up again, and rapid eye movement (REM) sleep begins. Most dreaming occurs during REM sleep.

You normally go through four to six sleep cycles a night, cycling between NREM and REM sleep in about 90 minutes. Your REM stage usually lengthens with each cycle as the night progresses. Sleep disorders can disturb this sleep process.

Polysomnography monitors your sleep stages and cycles to identify if or when your sleep patterns are disrupted.

Your doctor may recommend polysomnography if he or she suspects you have:

  • Sleep apnea or another sleep-related breathing disorder. In this condition, your breathing repeatedly stops and starts during sleep.
  • Periodic limb movement disorder. In this sleep disorder, you involuntarily flex and extend your legs while sleeping. This condition is sometimes associated with restless legs syndrome.
  • Narcolepsy. You experience overwhelming daytime drowsiness and sudden attacks of sleep in this condition.
  • REM sleep behavior disorder.  This sleep disorder involves acting out dreams as you sleep.
  • Unusual behaviors during sleep. Your doctor may perform this test if you do unusual activities during sleep, such as walking, moving around a lot or rhythmic movements.
  • Unexplained chronic insomnia. If you consistently have trouble falling asleep or staying asleep, your doctor may recommend polysomnography.

© 1998-2015 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of use