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Sleep complaints or the result of examinations may be reason to examine your cerebrospinal fluid. This fluid is obtained via a lumbar puncture.
At the bottom of the spine is a cavity filled with cerebrospinal fluid. To take a sample, the doctor will puncture between your lumbars in the lower back. The examination takes about five minutes. After the puncture, you must stay in bed for at least an hour. You must refrain from strenuous physical exercise for several days.
Preceding this examination, you will receive more information on the course of the examination and the practical matters you must reckon with.
A lumbar puncture is mostly done to indicate or preclude the diagnosis narcolepsy with cataplexy.