Utility of Acetazolamide-challenged CT Perfusion in Patients with High-grade Carotid Stenosis

cerebral hemodynamics (1). Neurological symptoms associated with carotid stenosis are mainly produced by thromboembolic stroke. They can be also attributed to altered cerebral hemodynamics (2). Hemodynamic factors have long been associated with the symptomatic status of stenosis, although their role is controversial (1). A percentage of patients have an insufficient collateral supply and so arterial stenosis can cause a reduction of pressure in the distal arterial vessels. However, the degree of stenosis does not accurately predict hemodynamic status of distal circulation (3). The impaired cerebral hemodynamics can be identified either by detecting brain tissue at risk or by demonstrating an impaired vasodilatatory response (4). The impaired cerebrovascular reserve (CVR) capacity is reported to be associated with an ischemic stroke, even in asymptomatic patients, as it has been found to be significantly reduced in low-flow infarctions compared with thromboembolic infarctions in patients