Detection of early-stage keratoconus using an auto-keratometer: multicenter study

Session Details

Session Title: Presented Poster Session: Corneal Cross-Linking

Venue: Poster Village: Pod 3

First Author: : T.Kojima JAPAN

Co Author(s): :    T. Nishida   T. Nakamura   Y. Satoh   A. Tamaoki   K. Ichikawa   K. Ichikawa        

Abstract Details

Purpose:

Early detection of keratoconus is essential to maintain visual function. Since the auto-ref/keratometer is available worldwide, we evaluated the feasibility of early-stage keratoconus screening using the auto-keratometer measurement values.

Setting:

Nagoya Eye Clinic, Japan Community Health Care Organization Chukyo Hospital, Japanese Red Cross Gifu Hospital, Satoh Yuya Eye Clinic, and Iida Municipal Hospital.

Methods:

Grade 1 keratoconus patients and age-/sex-matched healthy control subjects were retrospectively reviewed from patient charts at 5 different hospitals. The subjects were randomly divided into two groups: one for creating the prediction equation and another for verifying it. Multiple logistic regression analysis was performed for the equation group. The diagnosis of keratoconus was set as a dependent variable, and auto-keratometer values, including the average, steep, and flat K values, astigmatism, and astigmatism axis classification, were set as the independent variables. The diagnostic probability was calculated from the regression equation and named as the Keratometer Keratoconus Index (KKI).

Results:

We selected 124 keratoconus eyes (patient age: 29.2 ± 14.8 years) and 198 healthy eyes (age of healthy subjects: 27.8 ± 17.3 years). A model was created by logistic regression analysis (p <0.001). Steep K (partial regression coefficient [β]: 1.825; odds ratio [OR]: 6.204), flat K (β: -1.025; OR: 0.359), and with-the-rule astigmatism (β: -4.309; OR: 0.013) were selected as independent variables. The area under the receiver operating characteristic (ROC) curve of KKI was 0.91; the cutoff value of KKI calculated from the ROC curve was 0.32. The sensitivity and specificity in the evaluation group were 82.3% and 88.1%, respectively.

Conclusions:

KKI is a promising parameter to detect early-stage keratoconus. If KKI is installed in the auto-keratometer worldwide in the future, there is a possibility that keratoconus will be detected early in many patients. If we can prevent the progression of keratoconus by treatment, such as corneal crosslinking, we believe there is a possibility that further deterioration of visual function can be prevented in many keratoconus patients.

Financial Disclosure:

None