Treatment planning and strategies for acousto-optic guided high-intensity focused ultrasound therapies

Abstract

Real-time acousto-optic (AO) sensing has been shown to non-invasively detect changes in ex vivo tissue optical properties during high-intensity focused ultrasound (HIFU) exposures. The technique is particularly appropriate for monitoring non-cavitating lesions that offer minimal acoustic contrast. This work employs a modeling-based approach to improve the AO sensing of lesion formation during HIFU therapy, to develop treatment strategies for the ablation of large volumes, and to assess the technique's viability and robustness in a clinical setting. The angular spectrum method is used to model the acoustic field from the HIFU source. Spatio-temporal temperature elevations induced by the absorption of ultrasound are modeled using a finite-difference time-domain solution to the Pennes bioheat equation. Changes in tissue optical properties are calculated using a thermal dose model, calibrated using experimental data. The diffuse optical field is modeled using an open-source GPU-accelerated Monte Carlo algorithm. The Monte Carlo algorithm is modified to account for light-sound interactions, using the acoustic field from the angular spectrum method, and to account for AO signal detection. AO signals are presented in the context of a photorefractive-crystal-based detection scheme, and are compared to signals obtained using standard optical detectors. [Work supported in part by the Whitaker International Program.]

High-Intensity Focused Ultrasound Lesion Detection Using Adaptive Compressive Sensing Based on Empirical Mode Decomposition

“…In recent years, researchers have shown that an optoacoustic imaging method can be used as a realtime and noninvasive method for determining the optical characteristics of the tissue during HIFU therapy. In a paper, Adams et al [12] indicated that this methods is especially suitable for monitoring nonbubble thermal HIFU lesions with a minimal acoustic contrast. In another work, Alhamami et al [13] showed quantitative measurements of optical properties of a coagulated HIFU thermal lesion versus a native untreated tissue and demonstrated an approximately fourfold increase in the amplitude of the optoacoustic signal generated in a HIFU-induced thermal lesion versus a native untreated tissue.…”

High-intensity focused ultrasound lesion detection using adaptive compressive sensing based on empirical mode decomposition

“…In a study, Adams et al . [ 12 ] indicated that this method is especially appropriate for monitoring nonbubble thermal HIFU lesions with a minimal acoustic contrast. In another paper, Alhamami et al .…”

Toward high-intensity focused ultrasound lesion quantification using compressive sensing theory

“…In recent years, researchers have shown that an optoacoustic imaging method can be used as a real-time and non-invasive method for determining the optical characteristics of the tissue during HIFU therapy. In a study, Adams et al 13 showed that this technique is especially suitable for monitoring non-bubble thermal HIFU lesions with a minimal acoustic contrast. In another study, Alhamami et al 14 presented quantitative measurements of optical properties of a coagulated HIFU thermal lesion versus a native untreated tissue and demonstrated an approximately fourfold increase in the amplitude of the optoacoustic signal generated in a HIFU-induced thermal lesion versus a native untreated tissue.…”