Andrew K. Dunn, Ph.D.

Andrew Dunn, professor in the Department of Biomedical Engineering and director of the Center for Emerging Imaging Technologies, will receive the 2017 Edith and Peter O’Donnell Award in Engineering from The Academy of Medicine, Engineering & Science of Texas (TAMEST) at its annual conference on Jan. 11.

The O’Donnell Awards were established to recognize and promote outstanding scientific achievements of the state’s most promising researchers.

Dunn has developed technology that allows us to see things we haven’t seen before in the human brain. Through his laser speckle imaging technique, we can now see blood flowing in the brain in real time, allowing us to see where clots are forming. This allows neurosurgeons to easily identify areas suffering from reduced blood flow and prevent strokes.

“He has developed this magnificient laboratory and exceptional research,” says Nicholas Peppas, the director of UT Austin’s Institute for Biomaterials, Drug Delivery and Regenerative Medicine and a Cockrell School professor who also holds appointments in the Dell Medical School and School of Pharmacy. “He’s been able to use advanced optical techniques to really see the very early stages of clots in the brain. This was not possible before he started working on it.”

The National Institutes of Health has awarded Professor Andrew Dunn with a four-year, $1.8 million RO1 grant to develop a new technique for imaging blood flow across the surface of the brain.

The technique, called multi-exposure speckle imaging (MESI), can be used to measure blood flow in patients undergoing neurosurgery and to provide quantitative information on blood flow changes after a stroke.

When patients undergo surgery for an aneurysm, they are first injected with a fluorescent dye that lights up perfused vessels and darkens blocked vessels in the brain. Neurosurgeons use this imaging as a guide to determine where to clip an artery. But often vessels have varying degrees of blood flow, and current imaging methods do not quantitatively measure blood flow. Current methods also have limitations because patients may be allergic to dyes, and a surgeon is only able to use this dye method once during a surgery.

Using multi-exposure speckle imaging shows higher blood flow in red areas and less in yellow areas, giving neurosurgeons more accurate information in real-time.

MESI is able to give a surgeon an exact measurement of how much blood is flowing where, without the use of a dye. The technique will provide neurosurgeons with accurate information in real-time, with no disruption to the surgical process. Professor Dunn and his lab are collaborating with Dr. Douglas Fox, a neurosurgeon at St. David’s Hospital, to translate the technology to the clinic.

MESI is also a tool that can provide quantitative imaging of blood flow after stroke. In the days and weeks after a stroke, the brain undergoes changes, growing new vessels to repair itself. Little is known about this remodeling process, but MESI will be able to provide measurements that could be helpful to drug developers in the design of drugs to restore blood flow to the brain. MESI may also be used as a tool to better inform stroke rehabilitation strategies by giving a better understanding of how the brain is remodeling itself.

WASHINGTON, D.C.— The American Institute for Medical and Biological Engineering (AIMBE) has announced the pending induction of Andrew K. Dunn, Ph.D., Professor and Herring Professorship Fellow, Biomedical Engineering, The University of Texas at Austin, to its College of Fellows. Dr. Dunn was nominated, reviewed, and elected by peers and members of the College of Fellows For leading contributions to optical imaging techniques for studying stroke physiology.