Corneal Topographic Analysis in Patients with Cataract

We studied the corneal curvature of 161 eyes in 101 patients,aged from 50 to 80 years (mean:63 years),with senile cataract using the To-pographic Modeling System (TMS) preoperatively.The results revealed that mean surface asymmetry index (SAI) was 0.36 and mean surface regularity index (SRI) 0.79.Simulated keratometry reading (Sim K) was 44.46 D,and 43.56 D.Minimun K reading was 42.60 D.The same patterns of corneal to-pography in both eyes were 50％ in 60 patients who had binocular examina-tion.Astigmatism less than 1 D was 23％ in 161 corneas.Corneal patterns in-cluded round (21.2％),oval 16.1％),symmetric and asymmetric bow-tie(22.2％),and irregular (40.4％).SRI and SAI of the irregular pattern were statistically higher than those of the round,oval and bow-tie patterns in our patients (P＜0.01 and P＜0.05).The results of our study determined that the cornea of eye with senile cataract preoperatively is not a perfect spherocylin-der.It is asymmetrically aspheric,with less curvature peripherally than cen-trally.