About Us

Affiliated Faculty


Rajiv Chopra

Rajiv Chopra, Ph.D.​

Associate Professor​
Department of Radiology, UT Southwestern​
NE6.252, 214-648-7745​
Lab website

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.​


Mi Deng

Mi Deng, Ph.D.​

Assistant Professor​
Department of Radiology and Department of Physiology, UT Southwestern​

Mi Deng, Ph.D., holds a bachelor's degree in biotechnology (2004) and a master's degree in developmental biology (2007) from Hunan Normal University in China. He then earned a doctorate in biochemistry and molecular biology (2012) from the University of Nebraska Medical Center. His doctoral research was on gene transcriptional regulation, protein post-translational modification and cellular signaling transduction. Dr. Deng joined UT Southwestern in 2012 as a postdoctoral researcher in Dr. Alec Zhang’s laboratory, where he investigated the biology and translational applications of hematopoietic and leukemia stem cells. He then joined the Physiology Department faculty as an Instructor. His current research is focused on the biology of tumor microenvironment, and translational oncology of therapeutic antibody development and cell-based immunotherapy.​ Dr. Deng became Assistant Professor​ in May 2017.


David Fetzer

David Fetzer, M.D.

Assistant Professor​
Medical Director of Ultrasound​
Department of Radiology, UT Southwestern​
NE6.236, 214-648-7770​

David Fetzer's complimentary background in imaging science and interest in translational research constitute the basis for his work in multimodality testing and quantitative imaging, particularly in metabolic, hepatobiliary, pancreatic, thyroid, and lymph node imaging.  ​

Dr. Fetzer is also Director of the Collaborative for Advanced Clinical Techniques in Ultrasound (CACTUS), a clinical laboratory drawing upon expertise from radiologists, medical physicists, industry partners, and various medical specialists focused on cutting edge clinical care and establishing an environment for clinical and translational research in ultrasound.​


Ken Hoyt

Kenneth Hoyt, Ph.D., M.B.A.

Associate Professor​
Department of Radiology, UT Southwestern​
Department of Bioengineering, UT Dallas​
D1.204, 214-648-5096​
Lab Website

Dr. Hoyt is trained in acoustics, bioinstrumentation, mathematical modeling, signal and image processing, and medical imaging. He holds a bachelor's degree in electrical engineering, and master's and doctoral degrees in biomedical engineering. His academic training was enhanced by a three-year postdoctoral fellowship at the University of Rochester, where he investigated soft tissue elasticity characterization and imaging of prostate cancer. Dr. Hoyt’s research is focused broadly on the development and use of ultrasound (US) technology for applications related to imaging of diseased tissue, therapy, and drug delivery. This research is categorized by four main pillars described as: Tissue elasticity imaging, quantitative US imaging using microbubble (MB) contrast agents, molecular US imaging, and US-stimulated drug delivery and treatment.​


Matthew Lewis

Matthew Lewis, Ph.D.

Assistant Professor​
Department of Radiology, UT Southwestern​
NE6.250, 214-648- 7751​


Shashank Sirsi

Shashank Sirsi, Ph.D. ​

Assistant Professor​
Department of Radiology, UT Southwestern​
Department of Bioengineering, UT Dallas​
D1.204, 214-648-5095​
Shashank.Sirsi@utdallas.edu​ ​
Lab Website

Dr. Sirsi is an expert in ultrasound contrast agents formulation for imaging and drug delivery applications. He holds bachelor's and doctoral degrees in biomedical engineering. He is adept in designing tailored ultrasound contrast agents for perfusion imaging, molecular imaging, and drug delivery, and has authored several publications and reviews in this field, as well as successfully competed for NIH grant funding. His area of research is highly multidisciplinary and involves collaborations with vascular biologists, ultrasound imaging experts, and radiologists.