MRI-guided focused ultrasound hyperthermia in combination with microbubbles for improved drug delivery at reduced power levels

摘要

Preclinical studies have shown that MRI-guided focused ultrasound (MRgFUS) can achieve spatially localized thermal exposures in the range of 41-43°C. This presents an advantageous scenario for a plethora of targeted therapeutics. It has been observed that the administration of contrast agent microbubbles (MB) can facilitate increases in temperature with focused ultrasound (FUS), resulting in accelerated ablations. FUS stimulated microbubbles have also been shown to increase vascular permeability which make them useful in a drug delivery context. Here we investigate the combination of MBs and FUS hyperthermia using MRI thermometry for temperature feedback as a means of improving drug delivery at a reduced power level compared to MRgFUS hyperthermia alone and report initial results with this approach.