By Sonal Noticewala
Since their introduction 50 years ago, lasers have gone from science fiction to everyday life. Now, laser technology is providing new alternatives to conventional methods in biomedicine, according to researchers who spoke on Feb. 19 at the 2011 AAAS meeting in Washington, D.C.
Lasers are helping to regenerate tissues and creating microscopic devices for delivering drugs, among other new uses in medicine. Despite the exciting possibilities, however, laser use must be carefully monitored because of potentially harmful effects.
Ilko Ilev, a senior staff fellow at the U.S. Food and Drug Administration Center for Devices and Radiological Health, uses lasers to study the interaction between light and tissues in the body. This approach, called biophotonics, is leading to new ways to diagnose and treat eye and brain disorders.
Lasers are highly beneficial as diagnostic techniques because they allow noninvasive probing of live tissue. However, heat and light exposure from lasers can cause burns and tissue damage.
“The efficacy and safety of laser therapeutic devices depend on evaluation of laser irradiation dose,” Ilev said. “There is a need for standard test methods to improve the accuracy and specificity of laser dosimetry measurements.”
New laser techniques that reduce the amount of light to which tissues are exposed during studies or procedures are making their way into the medical arena. One such device, called the femtosecond laser, was approved by the FDA for eye cataract surgery in May 2010.
Researchers also use lasers to probe the makeup of the basic components of cells.
“Lasers are instrumental in looking at single cells to get information about cell biology,” said Tuan Vo-Dinh, director of the Fitzpatrick Institute for Photonics at Duke University's Pratt School of Engineering in Durham, North Carolina.
Vo-Dinh uses sophisticated techniques that look at how different molecules scatter light from a laser. The pattern of the scattered light represents a unique fingerprint for each molecule, which eventually could lead to personalized therapies for patients based on specific DNA sequences.
Laser technology has also been applied to regenerate new cells and tissues. James Woo, a professor at the Institute of Regenerative Medicine at Wake Forest University's School of Medicine, uses lasers to construct supports called scaffolds that hold tissue to be implanted into patients. The laser serves as a drill, boring holes in the scaffold that serve to guide newly growing cells in the right direction.
Lasers also help engineers fabricate tiny medical devices that help improve how therapies are administered. Roger Narayan, a professor of biomedical engineering at North Carolina State University, uses lasers to create microneedles from ceramic materials and polymers. These tools can lead to more efficient intravenous drug delivery and reduce pain and injury at injection sites, compared with traditional methods.
From LASIK to microneedles, on large and small scales, on the bench and at the bedside, laser technology is burgeoning within biomedicine. “It is no wonder that laser use is growing at a double digit rate,” Narayan said.
Sonal Noticewala is a senior at Columbia University, majoring in neuroscience and behavior. She is conducting research on brain tumor migration, and she is an editor for the campus science magazine Columbia Science Review. Reach her at ssn2112@columbia.edu.
