he Caltech researchers' new technique allows them to
focus light deep inside biological tissue. In the experiment, the
researchers shined green laser light into the tissue sample seen here in
the center. Credit: Caltech/Benjamin Judkewitz and Ying Min Wang
Imagine if doctors could perform surgery without ever
having to cut through your skin. Or if they could diagnose cancer by
seeing tumors inside the body with a procedure that is as simple as an
ultrasound. Thanks to a technique developed by engineers at the
California Institute of Technology (Caltech), all of that may be
possible in the not-so-distant future.
The new method enables researchers to focus light efficiently inside biological tissue.
While the previous limit for how deep light could be focused was only
about one millimeter, the Caltech team is now able to reach two and a
half millimeters. And, in principle, their technique could focus light
as much as a few inches into tissue. The technique is used much like a
flashlight shining on the body's interior, and may eventually provide
researchers and doctors with a host of possible biomedical applications, such as a less invasive way of diagnosing and treating diseases.
If you crank up the power of light, you might even be able to do away
with a traditional scalpel. "It enables the possibilities of doing
incision-less surgery," says Changhuei Yang, a professor of electrical
engineering and bioengineering
at Caltech and a senior author on the new study. "By generating a tight
laser-focus spot deep in tissue, we can potentially use that as a laser
scalpel that leaves the skin unharmed."
Ying Min Wang, a graduate student in electrical engineering,
and Benjamin Judkewitz, a postdoctoral scholar, are the lead authors on
the paper, which was published in the June 26 issue of the journal Nature Communications.