Research Earns $1.8M NIH Grant

Professors K. J. Ray Liu (electrical and computer engineering and Institute for Systems Research) and Tom McAvoy (chemical and biomolecular engineering) are part of a University of Maryland research group that has received a $1.8 million grant from the National Institutes of Health (NIH) for an innovative technique to treat cancerous tumors in the lungs and upper abdominal region.

The research group's principal investigator is Warren D'Souza of the University of Maryland Medical School. The name of their research proposal is "Feedback Control of Respiration Induced Tumor Motion with a Treatment Couch."

The proposal addresses a common problem in radiation treatment: as the patient breathes, tumors may move, making the delivery of the radiation to the right place more difficult, and irradiating healthy tissue in the process.

At the center of the project is a real-time tumor motion compensation system using a treatment couch that will ensure accurate delivery of radiation without increasing patient discomfort, treatment time and cost, or biological effectiveness. The system simultaneously uses cinematic magnetic resonance imaging (cine MRI) to see the tumor as it moves, and an infrared camera to track markers on the patient's skin. It then correlates the position of the tumor with the position of the markers. This data is then used by a feedback control system to instruct the couch on which the patient is resting to move, adjusting itself to compensate for the patient's motion and effectively holding the tumor in a stationary position. The system will also learn to predict tumor position by analyzing data previously collected, and adapt to irregular tumor positions and movements.

This method, the team believes, will be far more efficient and effective than current solutions that involve the patient holding his or her breath—which can be difficult for an ill person—or gating, in which delivery is synchronized with the patient's breathing but increases treatment time and cost.

Published October 31, 2007