Dr. Chopra’s research is concentrated on the development of image-guided therapies. In particular, he has focused on the biomedical applications of high-intensity focused ultrasound (HIFU). Ultrasound is an attractive form of energy for therapeutic use because it can be transmitted through the body from external transducers, can be focused to very localized regions of a few millimeters, and can be generated from devices of multiple geometries ranging from large focused transducers to catheter-based devices. A unique set of capabilities arises when this technology is combined with magnetic resonance imaging (MRI). The ultrasound technology is able to deliver energy within the body noninvasively for applications such as mild heating or tissue ablation, and MRI is able to acquire images of the temperature distribution in the heated tissues during heating. Since the relationship between temperature, time and cell kill is well established, this creates a powerful closed loop method for treating soft tissues.
The other emerging application of HIFU is to potentiate or enable targeted delivery of agents within the body. Ultrasound can be used to trigger release from temperature-sensitive liposomes, or to noninvasively open the blood/brain barrier. These capabilities offer many possibilities for targeted drug delivery in the brain and other organs with pre-existing vascular barriers (retina, testicles, placenta, etc).
Dr. Chopra’s research has a preclinical component focused on novel applications of HIFU, and a translational component aimed at evaluating established HIFU approaches in patients.
Department of Radiology, UT Southwestern
NE6.250, 214-648- 7751