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Polysomnography
Last reviewed: 27.11.2021
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[Indications and contraindications to polysomnography
To date, indications for polysomnography include a wide range of somnological pathologies, in particular:
- insomnia (insomnia) of various etiologies;
- sleep apnea (respiratory depression in sleep) or obstructive sleep apnea-hypopnea syndrome;
- snoring;
- enuresis (bedwetting);
- idiopathic hypersomnia (increased duration of night sleep);
- narcolepsy (increased daytime sleepiness);
- periodic movement disorders in sleep ( restless legs syndrome );
- parasomnias (somnambulism, hypocrisy);
- sleep disorders in somatic, neurological and endocrine diseases.
This method of diagnosis is the only way to detect such violations of respiratory function during sleep, such as apnea and hypopnea, which are often accompanied by snoring. People with this pathology develop chronic oxygen deficiency of the brain and heart, which leads to serious diseases: coronary heart disease and central cerebral ischemia.
According to neurologists, there are practically no contraindications to polysomnography.
How is polysomnography performed?
Polysomnographic examination is carried out during night sleep, so the patient should come in the evening (after 20-21 hours) to the somnological laboratory (or specially assigned ward) of the clinic performing this type of diagnosis and having the appropriate equipment and specialists.
Before going to bed, the patient is connected to all recording devices by means of electrode sensors (about two dozen), which are placed on the surface of the skin in various places in such a way that it is possible to fix all the neurophysiological processes occurring during sleep.
So, during the night are tracked and recorded:
- bioelectrical activity of the brain ( electroencephalogram );
- heart rate and frequency ( electrocardiogram );
- blood oxygen level (peripheral pulse oximetry);
- intensity of respiratory movements of the chest (electroletizmography);
- the volumetric rate of air flow exhaled through the nose (respiration rate is measured by pressure sensors);
- body position and motor activity (video monitoring and myogram taken from the tibial muscles of the front surfaces of the thigh);
- the state of the muscles of the chin (electromyogram);
- movements of eyeballs in a dream (electrooculogram);
- snoring (its frequency and duration are recorded from a sound sensor located in the neck area).
What does polysomnography do in terms of diagnosing sleep disorders? Fixation and analysis of the neurophysiological changes recorded by the equipment in a dream allows specialists to construct a hypnogram - a computer graph of phases and sleep cycles, which, when compared with the normative age indices, reveals certain deviations in the patient's sleep characteristics. And this gives an objective reason for setting the right diagnosis.
For obvious reasons, the price of polysomnography on the sites of clinics and diagnostic centers is not indicated: to obtain specific data, you should contact the medical institution directly.
And according to what reviews about polysomnography leave patients of these institutions, the perception of the seriousness of problems with sleep and an understanding of their negative impact on health has not yet reached the required level. Yes, and fall asleep to the person, covered with sensors, it is not easy ...