Case Study for the May 17 Online Symposium, "Corneal Reshaping Update" with John Rinehart, OD

After reviewing this case study, please click here to visit the Online Symposium room on May 17, 9:00-10:30 pm Eastern.

I. Fitting Technique Options

1. Empirical
2. Diagnostic/Overnight Diagnostic
3. Topography-Based
4. Combination

Empirical fitting involves providing Ks and Subjective (sometimes topography) to the lab or lens designer.

Diagnostic/Overnight Diagnostic may require evaluation of fluorescein pattern on the open eye. Overnight diagnostic fitting where the best initial fit is determined though fluorescein pattern evaluation and/or analysis of topography. After one night of wear, prefit and current topography are compared to determine where the lens centered overnight.

Topography-based systems determine the initial lens from the corneal topography provided.

Most systems are a combination, because at some point they incorporate the use of topography.

Any discussion on the advantages of each technique or a particular design?

II. Problem-Solving

Decentered Lenses: High, Low, Lateral
Central Islands and False Central Islands
Not covered tonight due to time constraints:
    Physiological Problems: corneal staining
    Lens Adhesion/Binding

III. Basic Lens Change Options

Increase Sag
Decrease Sag
Increase or Decrease Diameter

Topographies: On left treatment zone decentered high. What was changed to get to topography on the right?

Low-riding lens: Cause? Solution? (Topography courtesy of Randy Kojima of Precision Technology Service.)

Lateral decentration: How do you fix this problem? (Topography courtesy of Jim Reeves, O.D.)

Central island/incomplete treatment over the corneal apex: What are the options to fix this problem?

False central island: How do you differentiate this from a "true" central island? What lens changes are necessary to remedy this problem?