The Castrop IOL Formula
摘要
The Castrop IOL formula is a theoretical Gaussian vergence formula that calculates the IOL power and refraction. The cornea is modeled as a thick lens where the posterior radii of curvature can be measured or assumed according to published normal values. The axial length is transformed in order to equal a segmental measurement. The IOL position is calculated with a multivariable regression formula using several anterior segment biometric variables. Two or three offset values (C, R, and H) can be used to correct systematic errors with a sequential or simultaneous optimization process. Performance on case series is better than classical formulas and compares favorably with modern ones.