Posters

Score vs Nagy scale for topographic (Orbscan11z ) diagnosis of keratoconus

Poster Details

First Author: K.Nagy EGYPT

Co Author(s):                        

Abstract Details

Purpose:

Evaluate the sensitivity and specificity of  Nagy SCALE for KC  diagnosis  by Orbscan11z topography data and compare it with SCORE topographic diagnosis.

Setting:

Prospective study of 240 eyes of  145   Patients 95 bilateral and 50 unilateral of KC and Kc suspect were included in this study  in the last 2 years. Orbscan 11 Z C. Topography was done to measure the C. thickness.

Methods:

Prospective study of 240 eyes of 145 Patients 95 bilateral and 50 unilateral of KC and Kc suspect were included in this study in the last 2 years. Orbscan 11 Z C. Topography was done to measure the C. thickness, C. power and posterior elevation. I-S value, 3 and 5 mm surface  irregularity difference between central thickness and thinnest point and distance of thinnest point from center of the cornea.

Results:

1. Overall sensitivity 78% and specificity were 96%  of Nagy Scale and it was 67% sensitivity and 90% specificity in Score . Nagy scale was more accurate for detection of early and subclinical  KC  than SCORE especially in cases of high K reading  and abnormal 5 mm surface irregularity   that was not detected by SCORE and its sensitivity & specificity reach up to 88% & 98 %  in early and subclinical KC There was 15% false negative Kc by score and about 12% false positive Kc and 20% no result by score and detected by Nagy scale

Conclusions:

Nagy scale is more accurate ,more sensitive and specific for evaluating subclinical, clinical and advanced Kc than score Orbscan topographic diagnosis and is reliable, very accurate tool especially  for evaluating sub clinical and KC suspect cases.

Financial Disclosure:

None