Juergen Strobel

Anterior optical coherence tomography: a non-contact technique for anterior chamber evaluation

PurposeTo assess a new non-contact anterior optical coherence tomography (OCT) system for anterior chamber evaluation.MethodsA new commercial 131-nm infrared light anterior OCT system was used for anterior chamber evaluation. Forty-four eyes of 35 subjects (18 normal subjects, 17 subjects with anterior chamber abnormalities) were enrolled in the study.ResultsEyes were divided into those with narrowed, broadened and normal anterior chamber depth. Anterior chamber angle dynamics were assessed in three patients with angle-closure glaucoma and cataract extraction. Anterior OCT was also used for visualization of the anterior chamber (OCT goniometry) in a subject with multiple local anaesthetic allergies with phobia regarding conventional contact gonioscopy.ConclusionsAnterior OCT is a new, easy-to-handle, non-contact technique that allows exact evaluation of anterior chamber parameters such as anterior chamber depth, chamber angle dynamics, corneal curvature and corneal thickness.

Comparison of space-maintaining capabilities of Healon and Healon GV during phacoemulsification

Purpose: To determine whether Healon GV® or Healon® (both sodium hyaluronate products) maintains space better during phacoemulsification with intraocular lens (IOL) implantation. Setting: Department of Ophthalmology, Friedrich‐Schiller‐University of Jena, Germany. Methods: This double‐blind, randomized clinical trial comprised 60 patients (30 Healon GV, 30 Healon) eligible for cataract surgery. Patients were evaluated 6 and 24 hours and 5 days postoperatively. A digital slide gauge mounted on an operating microscope was used to measure the distance between the iris and epithelial side of the cornea before surgery and before and after capsulorhexis. The distance between the anterior and posterior lens capsules (i.e., space in the capsular bag) was also measured before and after IOL insertion. The surgeon’s objective opinion of the products was evaluated. Results: The mean anterior chamber depth after capsulorhexis was significantly greater in the Healon GV than in the Healon group (P = .003). The mean distance between the anterior and the posterior lens capsules was significantly larger in the Healon GV than in the Healon group before and after IOL insertion. The subjective evaluation of space‐maintaining capacity during surgery also favored Healon GV. Healon was considered easier to inject and remove from the eye. Conclusion: Healon GV had better space‐maintaining capacity than Healon during cataract surgery with phacoemulsification and IOL insertion.

Ultrastructure of the Membrana Limitans Interna after Dye-Assisted Membrane Peeling

The purpose of this study was to investigate the ultrastructure of the membrana limitans interna (internal limiting membrane, ILM) and to evaluate alterations to the retinal cell layers after membrane peeling with vital dyes. Twenty-five patients (25 eyes) who underwent macular hole surgery were included, whereby 12 indocyanine green (ICG)- and 13 brilliant blue G (BBG)-stained ILM were analyzed using light, transmission electron and scanning electron microscopy. Retinal cell fragments on the ILM were identified in both groups using immunohistochemistry. Comparing ICG- and BBG-stained membranes, larger cellular fragments were observed at a higher frequency in the BBG group. Thereby, the findings indicate that ICG permits an enhanced separation of the ILM from the underlying retina with less mechanical destruction. A possible explanation might be seen in the known photosensitivity of ICG, which induces a stiffening and shrinkage of the ILM but also generates retinal toxic metabolites.

Scanning electron microscopic characteristics of commercially available 1- and 3-piece intraocular lenses.

Purpose To evaluate commercially available 1‐ and 3‐piece intraocular lenses (IOLs) with scanning electron microscopy (SEM). Setting Department of Ophthalmology and Electron Microscopy Center, University Hospital Jena, Jena, Germany. Design Experimental study. Methods Seven +23.0 diopter IOLs of different design and material and from different manufacturers were chosen for a detailed assessment. Scanning electron microscopy was used at standardized magnifications to assess typical IOL characteristics. The particular focus was the optic edge, the optic surface, the haptic–optic junction, and the haptic. Results All square‐edged IOLs had a curvature radius of less than 10 &mgr;m, while the mean optic edge thickness ranged between 216 &mgr;m and 382 &mgr;m. A 360‐degree square‐edged boundary was present in all 3‐piece IOLs and in a single 1‐piece model. Relevant production remnants on the optic edge were observed in 1 case. Regarding the haptic, 3‐piece IOLs had uniformly shaped fibers with a mean thickness of 177 &mgr;m ± 51 (SD) (range 116 to 220 &mgr;m). Chemical adhesives were used to attach the haptic in 1 case, where alterations of the IOL material were observed. In another case, the haptic fiber was press‐fitted into the optic, which resulted in bulging of the optic profile. Inspection of surface characteristics showed wavelike patterns in 2 IOLs. Conclusions Taking clinical relevance into account, all IOLs were of high manufacturing quality. Certain attention was paid in creating a sharp optic edge. Surface irregularities of 2 IOLs were attributed to the manufacturing technique. Methods for implementing the haptic–optic junction were diverse. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.