01/19/2021
THE EFFECT OF CORNEAL COLLAGEN CROSS-LINKING
Corneal collagen cross-linking has permanently transformed the management of keratoconus, representing the single most significant improvement in its treatment since the rigid contact lens and the corneal transplant.
Since the FDA authorization of corneal collagen cross-linking (CXL) in 2016, it has come to be the standard of care for progressive keratoconus. CXL is designed to stabilize the cornea and in the process prevent progression of keratoconus. As a result, early medical diagnosis and treatment is critical in the management of keratoconus, particularly in the pediatric populace which is at the greatest risk for progression. Primary care optometry is at the cutting edge for early diagnosis in many patients. It is incumbent on our profession to adopt techniques and modern technologies to properly diagnose patients with keratoconus as well as monitor for related progression. Any kind of patient, especially a pediatric patient, with lowered vision or a difficult refraction ought to be suspected and worked up to rule out this disease.
The management of keratoconus has always been a collective care model, with optometry making use of nonsurgical options like specialty contact lenses and with ophthalmology performing surgeries such as intra-corneal ring segments and different kinds of corneal transplants when contact lenses do not provide adequate vision or comfort. With CXL, the relation between optometry and our ophthalmology colleagues should be even closer, as ideally CXL needs to be done before adverse visual sequelae occur.
The treatment of these patients has changed from a model where practitioners could stand by and observe as keratoconus progressed to now being able to do something about it when progression is determined. This new model is similar to the management of glaucoma in many significant respects. Based on risk factors such as age, family history, level of disease and visual acuity, patients are monitored much more closely, and early intervention with CXL can be implemented to prevent progression. This will stop advanced disease states as well as the need for corneal transplants in the future.
It is important to keep in mind that although CXL is more than 90% successful at stopping the progression of keratoconus, a small percentage of patients will still progress and might need retreatment. Consequently, it is important to continue to monitor these patients for progression, even postoperatively.
CXL has also provided renewed interest in visual correction with surgical procedures such as topography guided PRK. In our Center, we have seen encouraging results using this technique as well, and other vision correction procedures for patients with keratoconus. Future blog posts will dive deeper into these encouraging techniques.
