Magnetic Resonance Imaging–guided High Intensity Focused Ultrasound (MRI and HIFU): Noninvasive Multimodality for Neurosurgery

Abstract

High-intensity focused ultrasound (HIFU) provides focal delivery of mechanical energy deep into the body. This energy can be used to elevate the tissue temperature to such a degree that ablation is achieved. HIFU under magnetic resonance imaging (MRI) guidance (MR-HIFU) is a completely non-invasive technology for accurate thermal ablation of a target tissue while neighboring tissues and organs are preserved. The combination of HIFU with MRI for planning, real-time monitoring and outcome assessment of treatment markedly enhances the safety of the procedure. Recent technological developments open the field of therapeutic application to the brain through the intact cranium and is a noninvasive treatment strategy for various brain diseases. Promising results of recent studies have been shown for the treatment of adenomyosis, malignant tumors of the prostate, breast and liver and for various intracranial applications, such as thermal ablation of brain tumors, functional neurosurgery and transient disruption of the blood-brain barrier. This review examines the physical principle and rapid development of MRI-guided HIFU (MRI and HIFU) methods over the past few years and discuss their future potential in neurosurgery.