The emmetropic and the iseikonic implant lens: computer calculation of the refractive power and its accuracy.

The preoperative calculation of the power of a lens prosthesis and the resulting aniseikonia is given, as well as diagrams for reading the emmetropizing and the iseikonizing power of the lens. The consequences of an inaccuracy in the measurement of the dimensional and refractive properties of the eyes are calculated. It can be concluded that the main determinant for an accurate prediction of the power of the intraocular lens prosthesis is the axial length measurement. Since this measurement is carried out by means of ultrasound biometry, it is necessary to emphasize the adequate application of this technique. The problem as to whether an emmetropizing, or an iseikonizing lens should be implanted may be solved with the data supplied by the computer program. A flow chart for this program is given in an appendix.