September 1, 2006 — Replacing the scalpel with a laser, a new cornea transplant procedure leads to faster recovery. Instead of a straight cut, the laser makes zigzag slices around the patient's eye and the donor cornea. The cuts interlock like puzzle pieces, so the new cornea fits in perfectly and surgeons don't have to stitch the eye as tightly.
IRVINE, Calif. -- Forty thousand Americans need a corneal transplant each year. The procedure typically involves a long and painful recovery. But now, a new twist has patients seeing better, quicker.
Sewing is her passion, but when Gwyneth Hughes lost the vision in her right eye, she thought she'd have to give up her favorite hobby for good. "When I felt I couldn't even thread a needle on the sewing machine, it was terribly frustrating," she says. But, she refused to give up. "I'm sort of a strong person and strong-willed. To be defeated with anything was really not me."
Hughes needed a corneal transplant, a procedure that typically takes more than six months to recover from. But ophthalmologist Roger Steinert offered her a new option. Instead of a blade, he uses a laser to cut out a patient's old cornea and replace it with a new one.
"The laser can create shapes that are simply impossible to create with conventional surgery," Dr. Steinert, of University of California, Irvine, tells DBIS.
The same patients who are candidates for traditional corneal transplants are almost always candidates for the laser version. Instead of a straight cut, the laser makes zigzag slices around the patient's eye and the donor cornea. The cuts interlock like puzzle pieces, so the new cornea fits in perfectly. That means surgeons don't have to stitch the eye as tightly. Patients heal faster and have a quicker recovery -- within weeks.
"For me personally, it's dynamite," Dr. Steinert says. "I mean, for the first time we're able to take technology and raise transplants to a new level."
Right now, the University of California, Irvine, is the only facility in the world that has a dedicated laser in the operating room to perform the procedure, but Dr. Steinert expects many more centers to adopt the technology soon.
Hughes had the new procedure about three months ago and now she's back to doing what she loves best -- sewing.
BACKGROUND: An opthalmologist and his team at the University of California in Irvine have invented a new laser surgery technique to perform cornea-transplant surgery. This new surgery can replace traditional handheld surgical blades and improve recovery time and vision for patients. The Irvine team performed simulated transplant surgery on 14 donated human corneas and compared their results to traditional transplant results. Clinical trials began this summer at UC-Irvine.
HOW IT WORKS: Cornea transplants have traditionally only been performed in severe cases, since the majority of transplant recipients don't see improvements in their vision for at least six months, and even then strong glasses or contact lenses are needed because of remaining distortions. The cornea is slow to heal, and the transplant can remain vulnerable to injury for the rest of the patient's life. The new technique allows for special inter-locking cuts -- akin to dowels in wood -- that enable the edges to interlock. The treated area heals much faster -- within three months -- and may be as much as 10 times stronger compared with conventional transplants. The vastly improved precision also means that the laser can create complex shapes impossible to achieve with conventional surgery. The cuts are made not with the round blade used for the past 50 years, but by the same kind of laser used in LASIK vision correction surgery. This laser fires 15,000 pulses of light over a single second.
LASING A PATH: Laser eye surgery uses a pulsed, tightly focused beam of light to vaporize a tiny portion of the cornea. By controlling the size, position and number of laser pulses, the surgeon can precisely control how much of the cornea is removed. Reshaping the cornea changes the focal point of the eye, resulting in corrected vision. In the Irvine technique, the laser pulses are so brief, that in one quadrillionth of a second, a pulse of laser light could travel only the width of three human hairs. This is incredibly precise and controlled: on its own, in one second light can travel around the equator of the Earth seven times. The pulses are controlled by sophisticated optics and a computer to ensure they target the correct sections of the cornea -- similar to how the perforations in paper sheets allow the paper to be torn cleanly.
Note: This story and accompanying video were originally produced for the American Institute of Physics series Discoveries and Breakthroughs in Science by Ivanhoe Broadcast News and are protected by copyright law. All rights reserved.
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