[Diagnosis of sleep disorders]

Sleep disorders encompass pathology of very diverse origin with clinical expressions as varied as insomnia, hypersomnia, breathing disorders, complex motor disorders, etc. Some of these processes can be diagnosed clinically, while for the evaluation, diagnosis and treatment of others a battery of tests are required that are carried out in a sleep laboratory. Given the complexity and the cost of these tests, their indication must be based on a suitable evaluation and clinical exploration of the subject. Besides establishing the pertinence of the indication of the study, such evaluation must establish the type of test to be carried out. We review the different diagnostic tests available in the sleep units: polysomnography, respiratory poligraphy, multiple sleep latency test, maintenance of wakefulness test, Osler test, video- EEG for sleep and actigraphy. We comment on basic aspects of these, both theoretical and practical.