A new optical tool could help brain surgeons find and examine cancerous tissue without the need for a risky biopsy of brain tissue. Jin U. Kang, an electrical engineer at Johns Hopkins University, said the device could allow a doctor to perform a “virtual biopsy” to locate a tumor and determine whether it is malignant. “And when it’s time to cut out the cancer,” he said, “these images could help a surgeon see and avoid healthy tissue.” The device uses ultrathin optical fiber to direct harmless low-power laser light onto an area a surgeon wants to examine. Optical coherence tomography enables the small portion of light scattered from the tissue sample to be collected and used to construct a high-resolution three-dimensional picture of the tissue at the cellular level. The images are far sharper than those produced by MRI or ultrasound equipment, Kang noted. In this demonstration using a model skull, ultrathin optical fiber directs harmless low-power laser light onto an area a brain surgeon wants to examine. Courtesy of Will Kirk, Johns Hopkins University. Kang, also a professor and chairman of the department of electrical and computer engineering at Johns Hopkins’ Whiting School of Engineering, is working with neurosurgeons in the university’s School of Medicine and with Russell Taylor, director of the Johns Hopkins-based National Science Foundation Engineering Research Center for Computer-Integrated Surgical Systems and Technology. The project recently was awarded $450,000 in federal stimulus package funds to develop the technology. The two-year grant has been provided by the Institute of Neurological Disorders and Stroke, part of the National Institutes of Health. The surgical tool has not yet been tested on human patients, but the federal grant will enable the researchers to begin animal and human cadaver testing in a matter of months. Trials on human patients could begin within five years.