Effects of rigid gas permeable contact lens use on the assessment of outcomes of corneal cross-linking for keratoconus

Session Details

Session Title: Presented Poster Session: Cross-Linking

Venue: Poster Village: Pod 2

First Author: : T.Kojima JAPAN

Co Author(s): :    T. Nishida   Y. Yoshida   Y. Mizuno   T. Nakamura   K. Ichikawa           

Abstract Details

Purpose:

Corneal crosslinking (CXL) is performed to halt the progression of keratoconus. Since most candidates for CXL are usually in an early stage of keratoconus, rigid gas permeable contact lenses (RGP) are often prescribed after CXL surgery. In the current study, we evaluated the effects of RGP use on the outcomes of CXL surgery.

Setting:

Nagoya Eye Clinic, Nagoya, Japan

Methods:

Forty-four eyes of 24 patients (average 24.2±6.4 years), who had no history of RGP use before CXL, had undergone CXL, and were examined 1 year post-CXL were retrospectively enrolled in the study. Patients were divided into 2 groups; Non-RGP group: no use of RGP after CXL, and RGP group: use of RGP after CXL. Stepwise multiple regression analysis was performed. The independent variable was a change in steep K-value, and dependent variables were use of RGP and other ocular parameters. Anterior segment optical coherence tomography (CASIA, TOMEY) was used to obtain corneal parameters, including steep K-value.

Results:

In the Non-RGP group, steep K-value decreased significantly after CXL (Pre-CXL: 51.15±6.79D, 1 year post-CXL: 50.56±6.57D p < 0.0001); in the RGP group, there were no significant differences (pre-CXL: 55.23±7.55D, 1 year post-CXL: 51.91±6.62D, p = 0.33). Mean changes in steep K-value in the Non-RGP and RGP groups were -0.59±0.91D and -1.32±3.99D, respectively, suggesting changes in steep K-value show a larger variation in the RGP group. Posterior corneal curvatures did not differ significantly between the groups, pre- and post-CXL. Multiple regression analysis did not indicate RGP use as a variable determining change in steep K-value.

Conclusions:

Evaluation of CXL outcomes from only the anterior corneal curvature is interfered with by the use of RGP. Posterior corneal curvature analysis should be included to assess surgical outcomes after CXL.

Financial Disclosure:

None