Journal Article

513 Towards Obtaining One Billion Recordings Per Cubic Millimeter for the Validation of Focused Ultrasound Transducers: How Can Robust Systems Help With Translational Activities?

Thakor, Nitish, Theodore, Nicholas, Kerensky, Max, Manbachi, Amir, Liang, Ruixing, Curry, Eli

2022

Overview

OBJECTIVES/GOALS: The first aim was to construct a controlled and high resolution FUS water tank characterization system with 1 micron step-sizes. The second aim was to create two unique standardized protocols for mapping the generated acoustic field from FUS transducers; protocol one maps the full 3D field while protocol two rapidly detects changes to the original plot. METHODS/STUDY POPULATION: To accomplish aim one, the focused ultrasound mapping platform was constructed with a water conditioning unit for water degassing and temperature control, a three-axis stage with 1 micron step-size capabilities, and a data plotting software. To measure the outcomes of aim one, the water temperature was monitored, and axis step sizes were measured through ten independent axis translation recordings. To accomplish aim two, FUS acquisitions were executed at different resolutions. For FUS localization at the cellular level, a 1-5 micron step size is required. Once the initial scan was performed, duplicate scans were executed to detect inherent perturbations or errors in the system. Once calculated, the best methods of detecting true changes to FUS signals are proposed. RESULTS/ANTICIPATED RESULTS: The FUS characterization system maintained water temperature and performed 1 micron step-sizes. While pre-existing platforms have demonstrated a resolution of one thousand recordings per cubic millimeter, the proposed system (time and computing power willing) can record one billion recordings per cubic millimeter. In practice, a resolution of 20 micron was sufficient for non-cellular level FUS characterizations. Successive 2D scans were reliably stacked to form a 3D rendering of the generated acoustic field with the average focal point intensity yielding a 1% coefficient of variation between identical scans. This inherent variation can be used as the threshold of significance for true change detection; to rapidly detect changes to the FUS signal, sampling can be performed at regions of high baseline values. DISCUSSION/SIGNIFICANCE: Focused ultrasound medical devices are gaining popularity for treatments including tumor ablation, neuromodulation, and drug delivery; however, the field lacks a standardized method to characterize these FUS transducers. The presented platform and protocols enable a rigorous and high quality translation through verification and validation.

• Publisher: Cambridge University Press
• Subject: Drug delivery / Evaluation / Localization / Mapping / Medical equipment / Neuromodulation / Population studies / Translation / Tumors / Ultrasonic imaging / Ultrasound / Water temperature / Workforce Development