Carolyn Shih, MD, has performed countless cornea transplants, including DMEK on Robert Sohovich.

Cornea transplants restore vision

Cataract surgery and DMEK — a type of cornea transplant — were necessary for Robert Sohovich to regain his sight. His 20/25 vision is evidence of the progression of cornea transplants.

Robert Sohovich is an avid reader, continuously juggling several books at a time. In summer 2017, he tackled the The Last Lion, a 3,000-plus page, three-volume biography of Winston Churchill.

“It was so long the writer died before he finished it,” said Mr. Sohovich, referencing William Manchester, the book’s author who handed the project off to Paul Reid eight months before his death. “It took me about four-and-a-half months to finish. It wasn’t a continuous read but I worked at it pretty well.

“I have multiple titles going at the same time. It’s sort of like a buffet — whatever mood I’m in.”

As the year progressed, cataracts caused Mr. Sohovich’s eyesight to decline. His vision was normal during the day, but at night he saw more halos than a Pink Floyd concert.

“Bright lights were very annoying,” he said. “It can be difficult to drive at night because of the oncoming vehicles.”

Mr. Sohovich’s condition led him to Carolyn Shih, MD, director of clinical research and director of refractive surgery at Northwell Health’s Department of Ophthalmology. Dr. Shih identified the cataracts, as well as a condition called Fuch’s Dystrophy where the pump cells in his cornea, the “windshield” to his eye were prematurely failing, creating a film and blurry vision. He needed a transplant.

It can be quite stressful to have any surgery, let alone surgery on your eyes. Dr. Shih performed the cataract removal, as well as a Descemet’s membrane endothelial keratoplasty (DMEK) — a type of cornea transplant — in March and April. As of early May, Mr. Sohovich’s vision was 20/25. He praised Cecilia Francisquini, surgical coordinator, and several others in the Department of Ophthalmology for providing a seamless experience.

“It is absolutely amazing,” said Mr. Sohovich, a Flushing native and retired human resources controller for a major media company. “I’ve worn glasses to correct my vision for 55 years and I no longer need them. It’s almost like a miracle.”

The evolution of cornea transplants

Corneas are very different than other organs. Acting as a windshield to the eye, corneas need to be clear to see. Generally, reasons to have a transplant are due to infection or getting hit in the eye where the cornea (or windshield) becomes scarred. Dr. Shih noted that Northwell’s Department of Ophthalmology is unique because of its roster of cornea specialists. “We have seven,” she said. “Most places have one.” As a result, the department has been at the forefront of transplant techniques and technology.

“We are at the cutting edge of transplanting tissue,” she said. “In the old days, you used to cut out corneal scars or diseased corneas with a cookie cutter blade, called a trephine. Then we would take another trephine, cut a donor button, and sew it in with many sutures. Those are called penetrating keratoplasties.”

Penetrating keratoplasty (PK) was first conceived decades ago and are still performed regularly. PK is reserved for individuals with scarred corneas or very severe opacities in their cornea.

A newer form of transplant called endothelial keratoplasty (EK) has become a more common way to restore vision. EK can help improve the vision for individuals suffering from conditions such as Fuchs' dystrophy, bullous keratopathy, iridocorneal endothelial (ICE) syndrome or other endothelial disorders.

There are two types of EK — Descemet's stripping automated endothelial keratoplasty (DSAEK) and Descemet's membrane endothelial keratoplasty (DMEK). Both have revolutionized corneal transplantation.

“I think the cornea is like an onion,” Dr. Shih said. “The inner-most layer facing the iris is a pump layer. It’s supposed to pump out excess water. The rest of the layers are nice and clear. You have a finite number of those pump cells and can lose them with age, previous eye surgery or prematurely in conditions like Fuch’s Dystrophy. As a result patients feel like they are looking through a steamy haze and may have severe glare around lights at night.

“With DSAEK the incision is only maybe three or four millimeters. It’s very small and done on the side of the cornea, where you slip in the donor tissue — which is about 90 to 100 microns thick. We lift the graft with an air bubble which rises and tamponades the new donor to the host cornea. And without glue or without stitches, it will stick by itself.”

Dr. Shih said DSAEK patients can see 20/40 after three months, a significant improvement from older transplant procedures.

DMEK can improve vision to 20/20

DMEK replaces a sheet of pump cells that is 10-15 microns thick. Similar to DSAEK, an incision is made, removing the endothelium and Descemet membrane and the sheet is inserted. However, because this tissue is even finer, it is done through a 2.75-3.5 mm incision and may only require one stitch.

“DMEK patients may be on their back for a week whereas DSAEK patients are on their back for three days. But these patients get back 20/20 vision as opposed to 20/40 vision,” Dr. Shih said. “It’s the newest form and not a lot of doctors are doing it due to the complexity of the procedure.”

Dr. Shih notes that the Northwell Department of Ophthalmology has performed about 100 DMEK procedures. She said the corneal specialists at Northwell also perform deep anterior lamellar keratoplasty (DALK) procedures, where surgeons remove all other layers of the cornea (except the inner layer) for those who have a healthy inner layer but scarring on the outside.

“Our goal is to provide the latest technology and the best options for healing our patients and helping them to see again,” Dr. Shih said.

Northwell's Department of Ophthalmology houses nationally and internationally renowned physicians across 21 facilities.


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