Usefulness of Ocular Response Analyzer in Diagnosis of Keratoconus

Poster Details

First Author: S.Kim SOUTH KOREA

Co Author(s):    J. Lee   J. Lee   H. Jeon        

Abstract Details

Purpose:

To evaluate efficacy of Ocular Response Analyzer (ORA®; Reichert Ophthalmic Instruments, Buffalo, NY) in diagnosis of Keratoconus, compared with normal eye.

Setting:

Department of Ophthalmology, Medical Research Institute, Pusan National University Hospital, Pusan, Korea

Methods:

The fifty-six keratoconic eyes (group 1) and 23 normal eyes (group 2) involved in this study. Eyes were diagnosed as keratoconus based on clinical examination and corneal topography. The corneal hysteresis (CH), corneal resistance factor (CRF), keratoconus index was measured by Ocular Response Analyzer between keratoconic and normal eyes.

Results:

The K-value measured by Pentacam was 49.2 Diopter (41.9-67.6D) in group 1, 43.3 Diopter(38.5-47.1D) in group 2. The central corneal thickness(CCT) was 494.0? (380-577?) in group 1, 561.7? (444-659?) in group 2. Two values showed significant differences between two groups (p=0.000, 0.000). There was significant correlation between CCT and CH in both groups (p=0.004, 0.027). The mean value of corneal hysteresis (CH) was 9.15 (2-12.9) in group 1, 10.8 (6.3-13.9) in group 2. The corneal resistance factor (CRF) was 8.18 (0.9-12.4) in group 1, 11.1 (6.7-14.1) in group2. The Keratoconus index (KI) was 0.27 (-0.71-1.00) in group 1, 0.79 (0.13-1.49) in group 2. All value showed significant differences between two groups (p=0.007, 0.000 and 0.000).

Conclusions:

Hysteresis was significantly higher in normal than in keratoconic eyes. It may be a useful measurement in addition to CCT, when assessing ocular rigidity. It may be good method to differentiate whether keratoconic or not in eye already have diagnosed as keratoconic by topography. FINANCIAL DISCLOSURE?: No