Dynamically Changing Field-of-View in the Comprehensive Neurovascular Exam

Introduction: Radiological assessment of neurovascular disease processes often requires multiple contrast-enhanced and non-contrast enhanced exams over a large FOV. We define a comprehensive neurovascular exam (CNVE) as the high resolution imaging of four major vessel groups: the aortic arch and great vessel origins, the carotid artery bifurcations and vertebral-basilar system, the intracranial arterial system, and the venous system of the brain. The ultimate goal of this work is to image all of these territories with high quality using a single standard dose of contrast material. To that end we hypothesize that by dynamically changing (scaling/shifting) the field-of-view (FOV) during an acquisition, high spatial resolution and high SNR images of the carotid arteries and intracranial venous system can be obtained. The proposed imaging protocol consists of: (i) a large FOV, low-dose, time-resolved acquisition that provides diagnostic information of contrast bolus dynamics including transit times and directionality of flow and serves as a timing bolus [1,2], and (ii) a high spatial resolution contrast-enhanced exam that implements dynamic change of the FOV in order to image the carotid arteries and then the intracranial venous system.