Photoacoustic computed tomography of mechanical HIFU-induced vascular injury

Mechanical high-intensity focused ultrasound (HIFU) has been used for cancer treatment and drug delivery. Existing monitoring methods for mechanical HIFU therapies such as MRI and ultrasound imaging often suffer from high cost, poor spatial-temporal resolution, and/or low sensitivity to tissue's hemodynamic changes. Evaluating vascular injury during mechanical HIFU treatment, therefore, remains challenging. Photoacoustic computed tomography (PACT) is a promising tool to meet this need. Intrinsically sensitive to optical absorption, PACT provides high-resolution imaging of blood vessels using hemoglobin as the endogenous contrast. In this study, we have developed an integrated HIFU-PACT system for detecting vascular rupture in mechanical HIFU treatment. We have demonstrated singular value decomposition for enhancing hemorrhage detection. We have validated the HIFU-PACT performance on phantoms and in vivo animal tumor models. We expect that PACT-HIFU will find practical applications in oncology research using small animal models. (c) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

The study developed an integrated HIFU-PACT system for detecting vascular rupture in mechanical HIFU treatment. They demonstrated the use of singular value decomposition to enhance hemorrhage detection and validated the system's performance on phantoms and in vivo animal tumor models. This PACT-HIFU system is expected to have practical applications in oncology research using small animal models.