Wednesday, June 25, 2008

Tracking Radiation in Tumors

According to Purdue University, researchers are creating a wireless device that can be injected into tumors to let doctors know the precise dose of radiation received and be able to locate the exact position of tumors during treatment. Because organs and tumors shift inside the body during treatment, a new technology is needed to tell doctors the exact dosage of radiation received by a tumor.

The information obtained could more effectively kill tumors, said Babak Ziaie, an Associate Professor in the School of Electrical and Computer Engineering and a researcher at Purdue’s Birck Nanotechnology Center. Ziaie leading the team testing the prototype wireless implantable passive micro-dosimeter said “the device could be in clinical trials in 2010.”

Conventional imaging systems can provide a three dimensional fix on a tumor’s shifting position during therapy. However, these methods are difficult to use during radiation therapy, are costly, and sometimes require x-rays, which can damage tissues when used repeatedly.

The new device uses RFID technology which does not emit damaging x-rays. The device does not have batteries and is activated with electrical coils containing a miniature version of dosimeters worn by workers in occupations involving radioactivity. The tiny dosimeter provides up-to-date information about the cumulative dose a tumor is receiving over time. Since the technology does not require intricate circuitry, the device can be easier and less expensive to manufacture than more complex designs.

The device has a diameter of about 2.5 millimeters and is about 2 centimeters long so that it is small enough to fit inside a large-diameter needle for injection with a syringe. The current size is small enough to be used in tumors, but researchers are working to shrink the device to about half a millimeter in diameter and to half of its current length.

The researchers were funded by NSF and recently received a two year grant from NIH to continue the work. The researchers are working to simplify the fabrication process so that the devices can be manufactured inexpensively. In addition the researchers are working with the University of Texas Southwest Medical Center at Dallas.

For more information, email Babak Ziaie bziaie@purdue.edu.