The Ultrasound Brain Helmet: Early Human Feasibility Study of Multiple Simultaneous 3D Scans of Cerebral Vasculature Brooks D. Lindsey*, 1 Nikolas M. Ivancevich*, John Whitman*, Edward Light*, Matthew Fronheiser*, Heather A. Nicoletto†, Daniel T. Laskowitz†, Stephen W. Smith* *Department of Biomedical Engineering, Duke University, Durham, NC, USA; †Division of Neurology, Duke University Medical Center, Durham, NC, USA ABSTRACT We describe early stage experiments to test the feasibility of an ultrasound brain helmet to produce multiple simultaneous real-time 3D scans of the cerebral vasculature from temporal and suboccipital acoustic windows of the skull. The transducer hardware and software of the Volumetrics Medical Imaging real-time 3D scanner were modified to support dual 2.5 MHz matrix arrays of 256 transmit elements and 128 receive elements which produce two simultaneous 64° pyramidal scans. The real-time display format consists of two coronal B-mode images merged into a 128° sector, two simultaneous parasagittal images merged into a 128° x 64° C-mode plane, and a simultaneous 64° axial image. Real-time 3D color Doppler images acquired in initial clinical studies after contrast injection demonstrate flow in several representative blood vessels. An offline Doppler rendering of data from two transducers simultaneously scanning via the temporal windows provides an early visualization of the flow in vessels on both sides of the brain. The long-term goal is to produce real-time 3D ultrasound images of the cerebral vasculature from a portable unit capable of internet transmission, thus enabling interactive 3D imaging, remote diagnosis and earlier therapeutic intervention. We are motivated by the urgency for rapid diagnosis of stroke due to the short time window of effective therapeutic intervention. Keywords: Transcranial, ultrasound contrast, intracranial arteries, 3D imaging, phase aberration 1. INTRODUCTION A wide variety of cerebrovascular diseases which swiftly inhibit brain function and arise from disruption of the blood supply to the brain are collectively termed stroke. Stroke is the third-leading cause of death in the U.S., responsible for 160,000 deaths in the year 2000 with a prevalence of 11.3 per 1000, or 4,000,000 individuals. It is the leading cause of disability among adults in the United States, costing some $56 billion per year [1] . At present, intravenous treatment with the thrombolytic drug, tissue plasminogen activator (tPA) is the only USFDA-approved pharmacologic intervention demonstrated to improve mortality and functional outcome in ischemic stroke; however, intravenous thrombolysis is only effective when administered within three hours of the onset of symptoms [2] . Currently tPA may be underutilized by physicians due to the fact that observable symptoms vary widely depending on the location of cerebral ischemia, indicating a need for a diagnostic tool providing speed and accuracy sufficient to tailor the treatment to the individual patient during stroke onset and progression. Prolific advances in neuroimaging including visualization of cerebrovascular changes via computed tomography angiography (CTA), magnetic resonance angiography (MRA), and traditional digital subtraction angiography have enabled a more complete understanding of the pathophysiology of stroke and have improved the safe management of stroke patients [3] . To this set of innovations we contribute our ultrasonic imaging system capable of providing multiple three- dimensional scans as a real-time, portable, non-invasive technology for the rapid evaluation of stroke patients. Providing an ultrasound solution addresses concerns associated with the cost, availability, complexity, and ease of use of these other modalities. We believe that the flexibility and portability of modern ultrasound systems make this modality a Corresponding Author: Brooks Lindsey, Box 90281, Duke University, Durham, NC 27705. Tel: (919) 660-5449, Fax: (919) 684-4488, Email: bdl14@duke.edu Medical Imaging 2009: Ultrasonic Imaging and Signal Processing, edited by Stephen A. McAleavey, Jan D'hooge Proc. of SPIE Vol. 7265, 726503 · © 2009 SPIE · CCC code: 1605-7422/09/$18 · doi: 10.1117/12.810644 Proc. of SPIE Vol. 7265 726503-1