The eyes have it

Corneal transplant innovation allows patients to recover sight sooner

Story and Photo by Colin Zak

For years, Brett Williamson’s right eye could only make out blurry shapes and colours.

“The vision in my right eye was so blurry, even glasses couldn’t correct it,” he says.

Williamson, 40, is now seeing clearly after undergoing a new corneal transplant procedure known as Deep Anterior Lamellar Keratoplasty (DALK) this past July. The innovative procedure allows patients to recover in half the time of conventional transplant surgery, and Williamson was able to return to his job as a produce manager within a month.

“The day after the surgery, I was able to make out that first letter on the vision chart. It was amazing – I couldn’t do that before,” he says. “I was surprised how great I felt after a few short days.”

For one in three patients receiving a corneal transplant, only the outer layers of the cornea need to be replaced rather the entire cornea. DALK replaces those outermost layers, while preserving the healthy inner layers. The procedure allows patients to recover in three weeks.

“With DALK, a patient’s vision recovers much faster, which means they can get back to work or school sooner than ever before. It also reduces the rejection rate to almost zero, which ultimately reduces the need for more surgical time and donor corneas to perform follow-up procedures,” says Dr. Thaddeus Demong, ophthalmologist at Demong Associate Eyecentre in Calgary, which is contracted by Alberta Health Services (AHS) to perform corneal transplants.

DALK involves removing the damaged outer layers of the cornea using a circular rotating blade. An air bubble is then injected under the surface to separate the healthy innermost layers, and the remaining damaged tissue is delicately trimmed away. Donor tissue is then placed over the open area and stitched into place. The intricate procedure takes just over an hour to complete.

DALK was first performed in Edmonton in 2006, and Dr. Demong is one of three surgeons in the province now performing the procedure.

A similar procedure, known as Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK), is available for patients with diseases affecting only the inner layers of the cornea, also allowing patients to recover in about three weeks.

In Calgary, donor corneas are prepared and stored by AHS staff at Rockyview General Hospital’s Lions Eye Bank, and are then used in transplant surgery at non-hospital surgical facilities around the city.

“It’s critical for people to speak with their family about their wishes regarding organ and tissue donation,” says Mijana Ridic, Manager of Lions Eye Bank.

Williamson says receiving a corneal transplant has improved his quality of life.

“I felt great a few short days after the procedure,” he recalls. “There was no pain or discomfort after a month or even going back to work.”