The purpose of this study is to determine the relationship between sleep disorders and cerebral hemodynamics.

Sleep disorders continue to be the most unrecognized modifiable risk factor for stroke. The relationship between sleep disorders and vascular risk factors and stroke has been well-documented but not fully understood. The investigators hypothesize hemodynamics impairment to be its potential mechanism. It has been reported that sleep-related breathing disorder, a type of sleep disorders, contributed as a risk factor for stroke through hemodynamic and hematologic changes. The purpose of this study is to determine the relationship between different kind of sleep disorders and cerebral hemodynamics, including OSHAS, RLS, RBD, narcolepsy, etc. The dynamic cerebral auto-regulation (dCA) and Transcranial Doppler (TCD) will be used to evaluate cerebral hemodynamics.

Inclusion Criteria:

• patients with sleep disorders
• meet the Diagnostic Criteria for Sleep Dyssomnias
• sufficient bilateral temporal bone windows for insonation of the MCA

Exclusion Criteria:

• middle cerebral artery (MCA) and/or other intracranial and/or extracranial major vascular 4 stenosis/occlusion, as diagnosed by a transcranial Doppler
• having a prior symptomatic cerebral vascular disease
• current arrhythmia, hyperthyroidism, anemia and unstable blood pressure, which may undermine hemodynamic stability
• inability to cooperate sufficiently to complete the dCA examination

The investigators conducted a prospective study of consecutive patients with sleep disorders treated at the Department of Neurology, First Hospital of Jilin University, China, from March 2016 to March 2017. Each patient was diagnosed with intrinsic sleep disorders by two neurologists according to the Diagnostic Criteria for Sleep Dyssomnias.