Sleep Diagnostics Polygraphy(Sleep study) measures respiratory flow, chest wall and abdominal excursions as well as oxygen supply of the blood and heart rate during sleep. Relevant breathing disorders such as sleep apnea can be examined with this examination  Patients with already established sleep apnea therapy (CPAP, BiPAP) can monitor the effect of therapy by means of polygraphy. Examinations should take place annually. Thus, the therapy can be adapted if necessary and prolonged by means of prescription.