Optical biometry before and after excimer laser epithelial keratomileusis (LASEK) for myopia

PURPOSE. In order to select the correct intraocular lens (IOL) for implantation, it is important to measure the eye length (biometry). The IOL Master from Zeiss-Humphry is frequently used for such measurements. Because this instrument employs an optical method, any irregularities on the corneal surface or any disturbances in corneal transparency could lead to mistakes in the measurements. The aim of this study was to determine whether eye length measurements obtained at the University Eye Clinic Regensburg, Germany with the IOL Master before and after excimer laser epithelial keratomileusis (LASEK) show any changes. METHODS. Axial length was measured on 20 myopic eyes (-2.75 to -8.00 diopters) before and one month after LASEK using the IOL Master. RESULTS. The mean pre-operative eye length was 25.46 mm (SD±1.03) and the postoperative mean length was 25.38 mm (SD±0.99). There was a strong correlation between the pre- and post-operative eye lengths (Pearson correlation coefficient 0.998). CONCLUSIONS. Although LASEK can lead to increased light scattering due to irregularities of the corneal surface and changes in corneal transparency, there is no difference in biometry pre- and post-operatively. (Eur J Ophthalmol 2003; 13: 257-9)