Skull Thickness Prediction for Transcranial Ultrasound

The transmission of ultrasound (US) through the skull bone has been investigated for therapeutic and imaging applications. One of the primary obstacles to the effective application of transcranial US is bone-induced phase aberration due to geometric variations both within a subject and between subjects. The predictability of the transmitted US wavefield within the cranial vault is paramount to the development of clinically useful US-based procedures ranging from intracranial tumor ablation and drug delivery to intraoperative monitoring and hemorrhage detection. The present gold standard for assessing skull thickness for US phase aberration correction is x-ray computed tomography (CT). Because CT has several inherent limitations as compared to US (e.g., safety, cost, and convenience), there is an interest in US-based methods for skull thickness prediction.

The proposed study will investigate the potential for using US-derived data to perform aberration correction for the transcranial propagation of US. Specific details pertaining to human skull geometry will be statistically analyzed to formulate a framework by which US-based measurements will yield comparable aberration correction as CT measurements.

This study will involve benchtop experimentation with US transducers and specialized instrumentation; computer-based image processing (US and CT); and the use of human ex vivo calvarium specimens.