contact lens case reports
Loss of Ortho-k Effect?
Check the Lens Surface
BY PATRICK J. CAROLINE, FAAO, & MARK P. ANDRÉ, FAAO
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Figure 1. Scanning electron microscopy of a protein film on a GP. |
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Figure 2. BH's right lens with the protein film. |
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Figure 3. Fluorescein pattern of BH's right lens. |
Patients who have a history of success with corneal reshaping lenses occasionally present with complaints of a rather sudden loss in their orthokeratologic effect. In recent years, practitioners have identified surface deposition as a major contributing factor to this loss of effect.
Deposits begin to form on the surfaces of all contact lenses almost immediately following lens application. While some of these coatings are of little or no clinical consequence, a continual layering of the deposits can result in deposition of 5µm to 10µm in thickness (Figure 1). This can ultimately affect patient comfort, visual acuity and ocular health, and in the case of corneal reshaping, it can compromise the overall effect of the modality.
Losing Focus
Patient BH is a 26-year-old male who has a three-month history of successful corneal reshaping with Paragon CRT. His spectacle prescription before undergoing the therapy was 2.50 OU. Within seven days of beginning overnight lens wear, his uncorrected visual acuity became stable at 20/20 OU throughout the entire day.
BH returned at five months complaining that the duration of his clear uncorrected vision had decreased from all waking hours to eight hours. Examination showed both lenses coated with a protein film (Figures 2 and 3).
Removing the Culprit
BH had been using Unique pH (Alcon) for daily lens cleaning and disinfection. At this visit, we instructed him to incorporate one drop of SupraClens liquid enzyme (Alcon) into his daily lens care regimen and to contact us (via e-mail) with follow up.
One week later, BH responded with the following message:
"You asked me to let you know how the protein removal drops worked in restoring my vision to what it was before. After my appointment, I soaked my lenses in the SupraClens solution for four hours that night. The next day, I could already see much clearer than I could the day before. A few days later my vision, without the contact lenses, was back to being clear throughout the entire day."
A Solution for Success
In our experience, SupraClens has proven to be an important component to long-term patient success with modern corneal reshaping lenses.
Patrick Caroline is an associate professor of optometry at Pacific University and is an assistant professor of ophthalmology at the Oregon Health Sciences University. Mark André is director of contact lens services at the Oregon Health Sciences University and serves as an assistant professor of optometry at Pacific University.