Contact Lenses For Keratoconus

Contact lenses have historically been the first treatment option for people who have been diagnosed with keratoconus. Since keratoconus can be managed with one of many different contact lens designs, no single design is best for every stage of keratoconus. Since each lens design has its own unique characteristics, your physician carefully evaluates the needs of the individual situation to find the lens that offers the best combination of visual acuity, comfort and corneal health.

Visual acuity and comfort are simple to evaluate because the patient provides the feedback to the physician if the specific contact lens provides adequate vision and comfort. Corneal health on the other hand, is much more clinical and requires a trained physician to evaluate the health of your eye and any potentially harmful short and long-term effects of contact lens wear.

The Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study is a multicenter, observational study of 1,209 keratoconus patients enrolled in 1995-1996. This is an ongoing study meaning that the observaion of these initial patients is still active.

The purpose of the CLEK study has been to describe the clinical course of keratoconus, the relationships of the diseases visual and physiological manifestations and to best evaluate the patients quality of life. The study also tries to identify risk factors and protective factors that influence the severity and progression of keratoconus.

The study doesn't however, provide up-to-date information about current treatment considerations for keratoconus patients:

• Advancements in contact lens technologies
• The 2004 FDA approval for Intacs corneal implants for keratoconus providing a safe, low-risk surgical procedure for patients that are contact lens intolerant.
• Advancements in corneal transplant procedures for patients who are not candidates for Intacs corneal implants.

One might consider the above list as a guide for determining where in a keratoconus treatment continuum a patients best options can be presented however, further clinical evidence needs to be analyzed.

Publication Reference:
The CLEK Study confirmed previous reports of the increased likelihood of PK (Corneal Transplant) associated with corneal scarring, steeper keratometry values, poorer visual acuity, and poorer contact lens comfort. The CLEK Study is among the first to report an increased risk of PK associated with younger age, worse vision-related quality of life, and flatter contact lens fits. Knowledge of these factors is beneficial to clinicians in patient education and may be useful in disease management.

Baseline Factors Predictive of Incident Penetrating Keratoplasty in Keratoconus. Mae O. Gordon, Phd, Karen Steger-May, MA, Loretta Szczotka-Flynn, OD, MS, Colleen Riley, OD, MS, Charlotte E. Joslin, OD, Barry A. Weissman, OD, Phd, Barbara A. Fink, OD, Phd, Timothy B. Edrington, OD, MS, Harald E. Olafsson, OD, Karla Zadnik, OD, Phd and the CLEK study group. American Journal of Ophthalmology 2006;142:923–930.