To compare the predictive accuracy of the Barrett Universal 2 and SRK/T intraocular lens power calculation formulae in patients undergoing uneventful phacoemulsification cataract surgery.

This comparative study aims to compare the predictive accuracy of Barrett Universal II and SRK T intraocular lens power calculation formulas in patients undergoing uneventful phacoemulsification cataract surgery. A total of 100 patients will be randomized into two groups, with intraocular lens power calculated using either Barrett Universal II or SRK T. Postoperative refraction will be assessed on day 40 and prediction error will be calculated by comparing predicted refraction with actual postoperative refraction. The study will compare mean prediction error, mean absolute error, and the proportion of eyes achieving refractive outcomes within 0.50 diopter and 1.00 diopter. The influence of biometric parameters such as axial length and keratometry on formula accuracy will also be evaluated. The study aims to determine which formula provides better refractive predictability in routine cataract surgery.