Assessment of Basilar Artery Reactivity in Stroke and Subarachnoid Hemorrhage Using Wire Myograph

Abstract

Blood flow regulation of normal cerebral arteries is a critical and important factor to supply the brain tissue with nutrients and oxygen. Stroke insult results in a disruption or reduction in cerebral arteries' blood flow with subsequent brain tissue damage. Hemorrhagic stroke is one type of stroke and accounts for about 13 % of all of stroke insults. In this type of stroke, the cerebral artery breaks open and causes bleeding in or surrounding the brain. Subsequently, this bleeding causes blood vessels to constrict in a process called vasospasm, in which the vessels narrow and impede the blood flow to brain tissue. Hemorrhagic stroke is the major cause of prolonged constriction of cerebral arteries. This leads to partial brain damage and sometimes death in patients with aneurysmal subarachnoid hemorrhage. Among the key delicate techniques to assess small blood vessel functionality is the wire myograph, which can be utilized in several cerebral injury models including stroke. The wire myograph is a device that provides information about the reactivity, stiffness, and elasticity of small blood vessels under isometric conditions. In this book chapter, we describe the techniques involved in wire myography assessment and the different measures and parameters recorded; we describe the utility of this technique in evaluating the effects of subarachnoid hemorrhage on basilar artery sensitivity to different agonists.