Posters
Diagnostic ability of topography disparity and ocular residual astigmatism for the detection of clinical and subclinical keratoconus
Poster Details
First Author: D. Piñero Llorens SPAIN
Co Author(s): A. Martinez-Abad R. Perez-Cambrodi P. Ruiz-Fortes R. Soto-Negro A. Artola
Abstract Details
Purpose:
To evaluate the diagnostic value of ocular residual astigmatism (ORA) and topography disparity (TD) to discriminate between clinical and subclinical keratoconus and healthy corneas.
Setting:
Department of Ophthalmology (OFTALMAR), Vithas Medimar International Hospital, Alicante, Spain
Methods:
This study comprised a total of 61 keratoconic eyes (38 patients, 11-64 years) (keratoconus group), 19 subclinical keratoconus eyes (16 patients, 13-57 years) (subclinical keratoconus group) and 100 healthy eyes (100 patients, 4-72 years) (control group). In all cases, a complete corneal analysis was performed using a Scheimpflug photography-based topography system (Sirius, CSO). Anterior corneal topographic data was imported from it to the iASSORT software (ASSORT Pty. Ltd), which allowed the calculation of ORA and TD.
Results:
Mean magnitude of the ORA was 3.09±2.63, 1.04±0.45 and 0.73±0.61 D in the keratoconus, subclinical keratoconus and control groups, respectively (p<0.001). Mean magnitude of the TD was 5.35±4.21, 1.20±0.96 and 0.60±0.43 D in the keratoconus, subclinical keratoconus and control groups, respectively (p<0.001). Good diagnostic performance of ORA (cutoff: 1.19 D, sensitivity 83.6%, specificity 91.0%) and TD (cutoff: 0.90 D, sensitivity 80.0%, specificity 80.0%) was found for the detection of keratoconus. The diagnostic ability of these parameters for the detection of subclinical keratoconus was more limited (ORA: cutoff 0.93 D, sensitivity 63.2%, specificity 77.0%; TD: cutoff 0.72 D, sensitivity 73.7%, specificity 68.0%).
Conclusions:
The vector parameters ORA and TD are able to discriminate with good levels of precision between keratoconus and healthy corneas. For the detection of subclinical keratoconus, these parameters may be considered as additional parameters to perform an accurate detection of this condition.
Financial Disclosure:
NONE
