MR-Acoustic Radiation Force Mapping Can Quantitatively Predict Drug Delivery Following Ultrasound-Induced Blood Brain Barrier Disruption in Rodents

Benoit Larrat¹, Benjamin Marty¹, Mathieu Pernot², Mickael Tanter², Franck Lethimonnier¹, Sbastien Mriaux¹

In this work, blood brain barrier was opened in rats using focusing ultrasound under 7T MRI guidance. Displacements induced by the acoustic radiation force were imaged with a motion sensitized sequence. After injection of a Gd chelate contrast agent, T1 maps were acquired from which quantitative Gd concentration images were derived. The relationship between acoustic intensity and penetration of contrast agent in cerebral tissue was investigated. Our data show that radiation force imaging is an efficient guiding tool to adjust the quantity of delivered drug or contrast agent with ultrasound induced blood brain barrier disruption.