Corneal Crosslinking procedure performed at WRNMMC for first time
By AJ Simmons, WRNMMC Command Communications
The Department of Refractive Surgery at Walter Reed National Military Medical Center (WRNMMC) performed its first corneal crosslinking procedure on May 19, making it one of just three military treatment facilities to offer the procedure to service members and their families.
“The procedure is basically hardening and strengthening weakened corneas,” said Army Maj. (Dr.) Paul Houghtaling, an ophthalmologist at WRNMMC who performs the procedure. “We’re using a combination of [ultraviolet light treatments] and riboflavin eye drops to form crosslinks — or more chemical bonds — between the corneal lamellae.”
Houghtaling explained that the procedure is intended for patients diagnosed with keratoconus or post refractive ectasia — two conditions characterized by the weakening and thinning of the clear outer layer of the eye called the cornea.
Keratoconus, often referred to as KC, can cause decreased visual acuity and may even require a corneal transplant in some severe cases, according to Houghtaling. Post refractive ectasia, while very similar to keratoconus in symptoms, is seen in a small percentage of patients following a refractive eye surgery such as Lasik or Photorefractive Keratectomy (PRK).
Houghtaling explained that corneal crosslinking can halt the thinning of the corneas that is caused by keratoconus or post refractive ectasia by prompting the lamellae (the layered tissue of the cornea) to harden. This hardening, which typically occurs naturally in the corneas as humans enter their 40s or 50s, acts as a reinforcing agent similar in function to a bridge’s structural supports.
The goal of the corneal crosslinking procedure is to stabilize the eye and prevent the corneal deterioration from progressing further, according to Houghtaling. He also elaborated that without crosslinking, some patients might require specialized contact lenses or even a corneal transplant.
Corneal crosslinking, which has been performed in Europe since the early 2000s, received its FDA approval in the United States for treating progressive keratoconus and post refractive ectasia in April and July of 2016, respectively.
Houghtaling emphasized that the procedure stops the thinning and weakening of the corneas, but it does not reverse or cure the damage that has already been caused. Despite this, Houghtaling has high hopes for the future of corneal crosslinking. “…in the future, the goal would be to do a treatment where we can essentially reverse the damage or to fix the shape of the cornea and then harden it and strengthen it as it is,” he said.
Houghtaling added that earlier detection and a greater understanding of the causes of keratoconus are important steps to be taken in the future of its treatment.
In the immediate future, Houghtaling hopes to establish a referral process that would allow patients’ local eye doctors to determine if they require and are a candidate for corneal crosslinking. He explained that patients who are referred to his department would be assessed on several criteria to determine if they are a candidate. He pointed out that being diagnosed with keratoconus does not necessarily mean that corneal crosslinking is required.
To learn more about corneal crosslinking, keratoconus and post refractive ectasia, visit the WRNMMC Department of Ophthalmology’s webpage at http://www.wrnmmc.capmed.mil/Health%20Services/Surgery/Surgery/Ophthalmology/SitePages/Home.aspx or the National Keratoconus Foundation’s site at www.NKCF.org.