View clinical trials related to Functional Blood Flow Disorder.
Filter by:Rotation or flexion of the cervical spine is unavoidable during positioning for some surgical procedures as carotid endarterectomy, thyroidectomy and surgery of the shoulder. Rotation or flexion may reduce blood flow in the carotid or vertebral arteries and induce intraoperative cerebral ischemia with impact on the neurological outcome of surgery. Predominantly if the circulus willisii is incomplete because of congenital variation, collateral arteries may not be sufficient to compensate reduced blood flow in one carotid or vertebral artery. This may be aggravated by intraoperative hypotension in limits tolerable under normal conditions but fatal during impairment of vascular conductivity by positioning. The middle cerebral artery (MCA) is a final large scale pathway of cerebral blood flow and hence relevant reduction of flow in the MCA may serve as a surrogate parameter for relevant reduction of cerebral blood flow caused by carotid stretching or narrowing. Objective of this study is to investigate, if MCA blood flow in normal male and female subjects, aged 18 to 85 years, is reduced in extended and rotated cervical spine position in comparison to neutral position.