WhatsAppElectrophysiological Diagnosis of Sleep Disorders
The Sleep Laboratory is a diagnostic unit that records the physiological processes of the body during sleep and diagnoses sleep disorders objectively. Patients come to this unit for sleep tests, not for treatment; the reports are interpreted by a sleep specialist, neurologist or ENT specialist, who then draws up the treatment plan. The Academic Hospital Sleep Laboratory offers comprehensive sleep diagnostic services, including full-night polysomnography.
Contents
- What Is a Sleep Laboratory?
- Which Examinations and Tests Are Performed?
- Which Conditions Does It Help Diagnose?
- Which Departments Refer Patients to This Unit?
- How Does the Analysis Process Work?
- How Long Do Results Take?
- How Is the Report Interpreted?
- Sleep Laboratory at Academic Hospital
- Frequently Asked Questions
- References
What Is a Sleep Laboratory?
The Sleep Laboratory (Polysomnography Unit) is a diagnostic unit that simultaneously records data such as brain electrical activity, eye movements, muscle tone, oxygen saturation, respiratory parameters and heart rhythm during sleep. This unit does not provide treatment; it produces and reports diagnostic data. The treatment decision and its management are carried out by the relevant clinical department. A sleep test records through electronic sensors in bed throughout the night; it is painless and requires an overnight stay, but patients can return to their daily activities right away. The results contain important data that reflect not only sleep quality but also the patient's general cardiovascular and metabolic health.
Which Examinations and Tests Are Performed?
| Test | What it measures, when it is used |
|---|---|
| The gold standard sleep test, covering EEG, EOG (eye movement), EMG, airflow, oximetry, respiratory effort belts and a position sensor. Sleep architecture, the apnea-hypopnea index (AHI), oxygen desaturation time and snoring are assessed together. | |
| Diagnosis in the first half of the night and automatic CPAP titration in the second half, in the same night. | |
| Determination of the effective CPAP pressure in the laboratory for patients diagnosed with obstructive sleep apnea. | |
| Objective measurement of narcolepsy and excessive daytime sleepiness; it consists of consecutive short sleep measurements the following morning. | |
| Objective assessment of the ability to stay awake in safety-critical occupations (drivers, pilots). | |
| Recording of respiratory parameters at home with a portable device; used when sleep apnea is suspected in moderate to high risk groups. | |
| A protocol adapted for children to assess sleep disorders, night-time breathing problems and the relationship between epilepsy and sleep. |
Which Conditions Does It Help Diagnose?
- Obstructive sleep apnea (OSA) and hypopnea syndrome
- Central sleep apnea and complex sleep apnea
- Narcolepsy (with or without cataplexy)
- Periodic limb movement disorder (PLMD)
- Restless legs syndrome (night-time leg movements)
- REM sleep behavior disorder (moving or talking during sleep)
- Sleep fragmentation and non-restorative sleep
- Parasomnias (sleepwalking, night terrors, sleep paralysis)
- Assessment of the relationship between epilepsy and sleep
Which Departments Refer Patients to This Unit?
Sleep laboratory tests are performed only at a physician's request. The following departments are common sources of referral:
- Neurology: When narcolepsy, REM sleep behavior disorder or a link between epilepsy and sleep is suspected.
- Ear, Nose and Throat (ENT): Before or after surgical evaluation for snoring and obstructive sleep apnea.
- Pulmonology: In the assessment of sleep apnea accompanying hypoxia, COPD and respiratory failure.
- Cardiology: When a link between sleep apnea and heart rhythm disorders or heart failure is suspected.
- Pediatric Neurology / Pediatric ENT: In the assessment of pediatric sleep disorders, night-time breathing difficulty and adenoid hypertrophy.
How Does the Analysis Process Work?
The sleep laboratory process consists of several stages:
| Stage | What is done |
|---|---|
| Sleep complaints, medications and accompanying conditions are reviewed; the appropriate test type is chosen. | |
| The patient comes to the laboratory in the evening. Electrodes and sensors are placed on the head and body; they are painless surface electrodes and belts. | |
| All parameters are monitored continuously while the patient sleeps. A sleep technician checks the recording quality throughout the night. | |
| The sleep specialist scores the recordings in 30-second periods (epochs); sleep stages, the number of apneas and oximetry data are assessed. | |
| Test results are sent to the referring physician with a written report and graphical interpretation. |
How Long Do Results Take?
| Type of test | Time to result |
|---|---|
| 3-5 working days | |
| 24-48 hours | |
| 2-3 working days after the device is returned |
How Is the Report Interpreted?
The main measure is the apnea-hypopnea index (AHI): the number of apneas and hypopneas per hour. An AHI of 5-15 is classified as mild, 15-30 as moderate and above 30 as severe obstructive sleep apnea. Oxygen desaturation time and minimum SpO2 values also determine the intensity of treatment. The report is interpreted by a sleep specialist, ENT specialist or neurologist together with the clinical findings and symptoms.
The report also gives information on the distribution of sleep stages, sleep efficiency, latency times, snoring intensity and position-related changes. These data are used to choose the treatment method and in follow-up.
A referral request from your physician is required to book a sleep test at the Academic Hospital Sleep Laboratory.
Get InformationSleep Laboratory at Academic Hospital
The Academic Hospital Sleep Laboratory shares test results with the referring physician; the treatment plan is drawn up in the relevant clinical department. The laboratory works together with the following departments:
- Neurology: assessment of narcolepsy, REM sleep behavior disorder and the link between epilepsy and sleep
- Ear, Nose and Throat: surgical evaluation in snoring and obstructive sleep apnea
- Pulmonology: sleep apnea accompanying COPD and respiratory failure
- Cardiology: the link between sleep apnea, rhythm disorders and heart failure
- Pediatric Neurology: sleep disorders and night-time seizures in children
- Treatment of Sleep Disorders: treatment and follow-up based on the test result
Frequently Asked Questions
References
The general information given on this page about sleep tests, the diagnosis of sleep disorders and the interpretation of results is supported by the reliable health sources listed below.
- American Academy of Sleep Medicine (AASM), "Clinical Practice Guidelines", aasm.org
- National Heart, Lung, and Blood Institute (NIH), "Sleep Studies", nhlbi.nih.gov
- American Thoracic Society, "What Is Obstructive Sleep Apnea in Adults?", thoracic.org
The information on this page is for informational purposes only; it does not replace medical examination, diagnosis or treatment. Please consult a healthcare institution regarding your complaints.
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