Abstract:Background/Aims: To evaluate the effect of corneal collagen crosslinking with

Calcification of hydrophilic intraocular lenses (IOL) is a rare complication. We report about the uneventful replacement of an opacified hydrophilic IOL. The patient presented 4 years after uneventful cataract surgery with a reduction of visual acuity due to calcification of the IOL. Macroscopically, the optic and the haptics were opacified. Light and scanning electron microscopy revealed granular deposits on the external surface of the IOL and numerous fine granular deposits within the optic of the IOL which were distributed in a line parallel to the surface of the IOL.

Exposure to 20% ethanol should be 20 to 30 seconds as the number of vital epithelial cells rapidly decreased after that. Vitality of the epithelial flap is probably a crucial factor in the dampened wound response in LASEK compared to that in photorefractive keratectomy.

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.

LASEK alters ocular surface haemostasis and reduces corneal sensation in the early postoperative period. Subjective symptoms of dry eye were described during the first 2 months after surgery.

The endothelial cell density and structural and ultra structural evaluation of the different ablation frequencies (50, 200, 500 Hz) showed no specific side-effects that could be associated with higher repetition rates. The quality of the ablation was comparable in all three different laser ablation frequencies. The 500-Hz excimer laser can provide the same ablation quality as slower platforms, but can also offer the advantage of requiring less treatment time than other laser platforms with lower repetition rates.

. Purpose:  To evaluate the safety, efficacy, predictability and stability of laser in situ keratomileusis (LASIK) with a 1000‐Hz scanning spot excimer laser (Concept System 1000; WaveLight GmbH, Erlangen, Germany). Methods:  LASIK was performed on twenty eyes with myopia or myopic astigmatism (mean spherical equivalent refraction: −3.97 ± 1.72 dioptres (D); mean cylinder: −0.84 ± 0.77 D) using a microkeratome for flap creation and the Concept System 1000 for photoablation. Patients were examined preoperatively as well as 1, 3 and 6 months after the treatment. Manifest sphere and cylinder, uncorrected (UCDVA) and best corrected (BCDVA) distance visual acuity, corneal topography and pachymetry were analysed. Results:  We observed no adverse events that might have been associated with the use of a repetition rate of 1000 Hz. All eyes maintained or had improved BCDVA at 6 months after treatment when compared to preoperative values. Six months after LASIK, UCDVA was 20/20 or better in 85% and 20/25 or better in 100% of the eyes. The spherical equivalent refraction was within ±0.50 D in 95% of the eyes at 6 months after surgery. The refraction stayed stable over time; 95% of the eyes changed <0.5 D postoperatively. Conclusion:  LASIK with the prototype 1000‐Hz excimer laser was safe, efficient and predictable. The postoperative refraction was stable over time. There were no specific clinical side‐effects that might be associated with the use of such a high repetition rate.

Flap creation could be performed easily without any complications. The morphology and accuracy of the cuts were very reliable and precise. Histology showed a smooth cut.