Tabletop femtosecond lasers are already used in eye surgery, but researchers believe that they may be the future of microsurgery, offering benefits in applications inside the body, ranging from repairing the vocal cords to removing small tumors in the spinal cord or other tissues. Scientists at the University of Texas at Austin have developed a small, flexible endoscopic medical device fitted with a femtosecond laser “scalpel” that can remove diseased and damaged tissue while leaving healthy cells untouched.
The device was engineered with off-the-shelf parts and includes a laser capable of generating pulses of light a mere 200 quadrillionths of a second in duration. These bursts are powerful, but so fleeting that they spare surrounding tissue. The laser is coupled with a mini-microscope that provides the precise control necessary for highly delicate surgery.
Using a technique known as “two-photon fluorescence,” this specialized microscope relies on infrared light that penetrates up to one millimeter into living tissue, which allows surgeons to target individual cells or even smaller parts such as cell nuclei.
The entire endoscope probe package is thinner than a pencil and less than an inch long, and can fit into large endoscopes, such as those used for colonoscopies. The optics consist of three parts: commercial lenses; a specialized fiber to deliver the ultrashort laser pulses from the laser to the microscope; and a 750-micrometer MEMS scanning mirror. To hold the optical components in alignment, the team designed a miniaturized case fabricated using 3D printing.
Also: A miniaturized laser diode solution was developed for a variety of medical applications.