Posters

The role of ocular response analyzer in differentiation of forme fruste keratoconus from high corneal astigmatism

Poster Details

First Author: A.Kirgiz TURKEY

Co Author(s):                        

Abstract Details

Purpose:

The majority of keratoconic corneas can be diagnosed with corneal topography as these patients have a characteristic topographic pattern. The main problem is the detection of subclinical forms described as forme fruste keratoconus (FFKC). The corneal steepening and astigmatism formation may be found in the topographic maps of both FFKC and astigmatism cases. Although all astigmatic patients do not have keratoconus, distinction of patients with FFKC and astigmatism may be challenging. This study was conducted to determine the diagnostic accuracy of corneal biomechanical factors in differentiating patients with FFKC from patients with astigmatism.

Setting:

Department of Opthalmology, Bagcilar Training and Research Hospital, Istanbul, Turkey

Methods:

Fifty eyes with FFKC, 50 with astigmatism and 50 normal eyes, were investigated. All patients had a detailed ophthalmologic examination including slit-lamp evaluation, Goldmann tonometry, indirect fundoscopy, topography by Scheimpflug imaging, biomicroscopic anterior and posterior segment examination and corneal biomechanical and intraocular pressure (IOP) evaluation with Ocular Response Analyzer (ORA).

Results:

Although there was no statistically significant difference in IOPcc among the three groups, IOPg, CH and CRF were statistically significantly lower in FFKC group compared with other 2 groups (p<0.001). There were no statistically significant difference in IOPg, CH and CRF between astigmatism and control groups (p=0.99, 0.79 and 0.86, respectively). The area under the ROC curve (AUROC) was greater than 0.85 for IOPg (0.80), CH (0.85) and CRF (0.90) for discriminating between FFKC and controls; whereas the AUROC was greater than 0.85 for IOPg (0.80), CH (0.79) and CRF (0.85) for discriminating between FFKC and astigmatism groups.

Conclusions:

In differentiation of patients with FFKC from normal control cases or astigmatic patients; IOPg, CH and CRF may play a role especially in patients with suspicious results and ORA may be a valuable tool in diagnosis of FFKC which may support the topographic data. Further studies with larger groups are warranted to determine the exact role of ORA in differential diagnosis of FFKC.

Financial Disclosure:

NONE