Effects of measurement errors on refractive outcomes for pseudophakic eye based on eye model

With the Gullstrand–Le Grand eye model, the effects of various measurement errors on refractive outcomes for pseudophakic eye are studied. An equation to calculate the postoperative refractive error for pseudophakic eyes is derived. The accuracy to get a refractive error less than ca. 25 D is ±0.1 mm for the axial length, ±0.03 mm for the radius of the corneal anterior surface, ±0.12 D for the corneal power and ±0.16 mm for the postoperative anterior chamber depth (ACD). An error of 1 D in intraocular lens (IOL) power leads to a postoperative refractive error of −0.69 D. K-reading leads to a postoperative hyperopia from 0.18 to 0.74 D for eye with different refractive errors previously corrected. The constant velocity in ultrasound biometry assumption overestimates the axial length from 0.17 to 0.31 mm with actual axial length ranging from 21.31 to 32.31 mm. Errors in axial length, corneal power or radius of the corneal anterior surface and postoperative ACD play critical roles in determining the refractive outcomes. The constant-velocity assumption tends to overestimate the axial length. The change of the ratio of corneal anterior to the posterior surface is of minor importance for the overestimation of K-reading.