Corneal Cross Linking: Noah's Story
Noah DeFerraris is a 17-year-old high school senior who’s taking a heavy load of college prep courses, like AP calculus and biomedical innovations, courses where being able to see the classroom board is critical.
“At the beginning of my sophomore year, I started having problems seeing, especially in the classroom,” Noah admitted. “Even if I was sitting in the front row, I had to squint to read the board.”
When he went for his annual eye exam, his optometrist noticed Noah’s vision was much worse than the year before.
“Noah has worn glasses and contacts since the first grade,” said his mom, Rose DeFerraris. “But this was different. He couldn’t even read the giant ‘E’ on the eye chart. His vision was terrible.”
Noah’s optometrist suspected he might have a condition called keratoconus, a progressive thinning and distortion of the cornea causing blurred or hazy vision and sensitivity to bright light. Keratoconus affects about one in 2,000 people and is more common in children with allergies and Down syndrome, and is usually diagnosed in adolescence or early adulthood.
“Noah has severe allergies and asthma, and often has rubbed his eyes. The doctor thought that might have contributed to the condition,” Rose explained.
After a test to map the shape of his corneas, the doctor concluded that Noah indeed had keratoconus. Initially, Noah’s optometrist treated the condition with glass contact lenses, but they were uncomfortable and difficult for him to wear.
“Noah’s eyes were red all the time, and he was still having trouble seeing,” Rose said.
In her job with Liberty Public Schools, Rose said she frequently refers students to Children’s Mercy Kansas City, so she decided to contact the hospital about Noah.
“I called the main number and explained that my son had been diagnosed with keratoconus,” Rose said. “They scheduled an appointment for Noah to see Erin Stahl, MD, an amazing corneal eye specialist with a great bedside manner!”
Dr. Stahl confirmed Noah’s diagnosis, and told him about a new option to treat the condition called corneal cross linking. Children’s Mercy was the first pediatric hospital in the nation to perform corneal cross linking, a treatment approved by the Food and Drug Administration.
“Until recently, we treated keratoconus with glasses, then contact lenses, but at some point, scar tissue develops and the contact lenses no longer work,” Dr. Stahl explained.
For about 20 percent of patients, the next step is a corneal transplant, which is expensive, can be risky and requires a lengthy recovery period.
Though keratoconus can’t be cured, the goal of corneal cross linking is to halt the progression of the condition. The procedure is performed on an outpatient basis. Most patients heal quickly and are back to their usual routine in a week to 10 days.
During the procedure, Dr. Stahl makes an incision to loosen the superficial layer of the cornea. Drops of riboflavin, or vitamin B2, are dripped onto the eye every two minutes, along with anesthetic every five minutes, for a half hour. The riboflavin-soaked cornea is then exposed to ultraviolet light for another 30 minutes. The light strengthens the bond between the riboflavin and collagen molecules, stiffening their fibers and ultimately strengthening the cornea.
“This is actually a natural process,” Dr. Stahl explained. “Riboflavin is naturally in your tears, and once we reach about age 50, we become naturally cross-linked. But that takes more than 30 years.”
Dr. Stahl completed the first corneal cross linking procedures in February 2017. Noah’s first procedure was performed on his right eye in May 2017, and his left eye was completed in July 2017.
Dr. Stahl worked with Christina Twardowski, OD, optometry, to create a special pair of glass contacts that help Noah see 20/20. His eyes healed just in time for the start of his junior year of high school.
Now a year later, Noah said the procedure did what it was supposed to—stop the progression of the keratoconus. In addition to wearing the glass contacts, he will return to Children’s Mercy once a year until he turns 21 so that Dr. Stahl can be sure his vision remains stable.
In the meantime, he’s working hard, taking advanced placement courses to prepare for college, and a possible engineering major.
“I can see a lot of things I couldn’t see before, like road signs and the board,” Noah said. “I’m definitely glad I had the surgery. Dr. Stahl was great and my vision is better than ever!”