ACCURACY OF IOL CALCULATION IN CATARACT-SURGERY

The accuracy of IOL calculation using the SRK II formula was studied i n 515 cataract extractions with posterior chamber IOLs. All excessivel y myopic patients (8 patients) and those where we had predicted an emm etropic postoperative result, from a consecutive series of 994 patient s, were included, Preoperatively the patients were divided into differ ent groups according to their refractive status and the mean postopera tive refraction was calculated in each group. The mean postoperative r efraction increased almost linearly with increasing myopic status, The emmetropic group achieved a mean postoperative refraction of - 0.6 D, whilst in the most myopic group mean refraction was - 1.8 D, We belie ve that the SRK II formula is inaccurate for myopic eyes, and that new formulas are needed, taking into account all those factors that make up the dioptric power of an eye.