Optical and material analysis of opacified hydrophilic intraocular lenses after explantation: a laboratory study.

BACKGROUND: The opacification of hydrophilic intraocular lenses (IOLs) is a very rare complication in terms of absolute numbers. We report on the analyses of opacified Euromaxx ALI313Y and ALI313 IOLs (Argonoptics, Germany) using light and scanning electron microscopy, X-ray spectroscopy and optical bench analysis. METHODS: Opacified Euromaxx ALI313Y and ALI313 IOLs were explanted after patients presented with a decrease in visual acuity. The explants were sent to our laboratory and examined using light and scanning electron microscopy. The composition of the deposits was analysed using X-ray spectroscopy. The optical quality of the intraocular lens (IOL) was assessed using the OptiSpheric IOL PRO optical bench (Trioptics GmbH Wedel, Germany). Modulation transfer function (MTF) was measured at all spatial frequencies and United States Air Force (USAF) 1951 resolution target pictures were documented. RESULTS: Macroscopically, the entire optic was opacified in all IOLs. Light and scanning electron microscopy revealed numerous fine, granular, crystalline-like deposits, which were always distributed in a line parallel to the anterior and posterior surfaces of the IOLs. X-ray spectroscopy could prove the deposits consisted of Calcium and Phosphate. Measurements in the optical bench showed deterioration of MTF values at all spatial frequencies and the USAF target pictures demonstrated a significant reduction of brightness as well as resolution with the opacified IOLs. CONCLUSIONS: The calcification of hydrophilic IOLs only occurs rarely. The exact chemical composition of the deposits can be assessed by means of X-ray spectroscopy. Optical quality analysis of the explanted Euromaxx ALI313Y and ALI313 IOLs showed significant reduction of MTF values, which was confirmed by USAF target pictures.

Topical anesthesia for transpupillary silicone oil removal combined with cataract surgery.

PURPOSE: To assess safety of topical anesthesia for transpupillary silicone oil removal in combination with cataract surgery. SETTING: Department of Ophthalmology Mannheim, University of Heidelberg, Mannheim, Germany. METHODS: The clinical interventional study included 37 consecutive patients having transpupillary silicone oil removal combined with cataract surgery. Without exception, surgery was carried out in topical anesthesia for all patients. During the study period, there were no patients having transpupillary silicone oil removal in another type of local anesthesia than topical anesthesia. Topical anesthesia was achieved with oxybuprocaine 0.4% eyedrops installed 4 to 5 times prior to surgery. Cataract surgery was performed using the clear cornea technique with implantation of a foldable intraocular posterior chamber lens. Silicone oil was released through a planned posterior capsulotomy during cataract surgery prior to implantation of the intraocular lens (IOL). RESULTS: For all patients, surgery could be carried out in topical anesthesia without switching to peribulbar or any other type of anesthesia. None of the patients complained about severe pain intraoperatively or postoperatively. No severe complications such as expulsive hemorrhage, luxation of the IOL, or iris incarceration were encountered in any of the surgeries. CONCLUSION: Transpupillary silicone oil through a planned posterior capsulotomy during cataract surgery may be performed in topical surgery.

[Grid laser photocoagulation in diffuse diabetic macular edema]. / Grid-Laserkoagulation bei diffusem diabetischen Makulaödem.

BACKGROUND: To evaluate the clinical outcome of macular grid laser photocoagulation in the treatment of diffuse diabetic macular oedema. PATIENTS AND METHOD: The retrospective study included 30 consecutive patients (41 eyes) who were treated by macular argon green grid laser photocoagulation for diffuse diabetic macular oedema. Follow-up time was 31.4 +/- 19.6 weeks. RESULTS: Visual acuity decreased from 0.25 +/- 0.18 (range, 0.03 - 0.8) to 0.20 +/- 0.18 (range, 0.02 - 0.8) (P = 0.045), representing a change of - 0.9 +/- 2,32 lines. 5 (12.2 %) eyes gained in visual acuity, visual acuity remained unchanged for 23 (56.1 %) eyes, and 13 (31.7 %) eyes showed a visual loss of more than one line. In eyes with a baseline visual acuity > or = 0.2 (N = 24) visual acuity dropped from 0.36 +/- 0.15 (0.2 - 0.8; median 0.3) to 0.29 +/- 0.19 (0.05 - 0.8; median 0.2) (p = 0.038). 3 eyes (12.5 %) gained > or = 2 lines, 11 eyes (45.8 %) lost > or = 2 lines, 10 eyes (41.7 %) remained stable. Mean loss was - 1.63 +/- 2.53 lines. Eyes with a baseline visual acuity < or = 0.2 did not change significantly. CONCLUSION: In the present study mean visual acuity decreased in the whole population and especially in the subgroup with a baseline visual acuity of > or = 0.2 after macular grid laser photocoagulation for diffuse diabetic macular oedema. Mean visual loss was just below the predefined 2 lines. In view of these results and upcoming new pharmacological and surgical treatment modalities, the significance of grid laser photocoagulation should be re-discussed.