Evaluation of mechanical resistance to tearing of the anterior lens capsule after staining with different concentrations of trypan blue.

PURPOSE: To evaluate and compare the mechanical resistance to tearing of the anterior lens capsule opening after staining with different concentrations of trypan blue in ex vivo porcine eyes. SETTING: Semmelweis University, and Budapest University of Technology and Economics, Budapest, Hungary. DESIGN: Experimental study. METHODS: The study comprised 75 porcine eyes. The capsule was unstained in the Control Group (n = 25 eyes), 0.06% trypan blue was used to stain the capsule in Stained 1 Group (n = 25 eyes), and 0.1% trypan blue was used to stain the capsule in Stained 2 Group (n = 25 eyes). After capsulorhexis, the capsule openings were stretched with custom-designed testing equipment until they ruptured. The rupture force (RF), circumference stretching ratio (CSR), and secant modulus at 10 mN (SM10mN) and 50 mN (SM50mN) were evaluated. RESULTS: In total, 75 eyes were enrolled. There were no statistically significant differences in the RF (P = .8924) or CSR (P = .3876) among the groups. There were no statistically significant differences in the SM10mN (P = .8215) or SM50mN (P = .4184) among the groups. CONCLUSIONS: In this porcine eye model, the trypan blue concentrations that are routinely used in cataract surgery had no effect on capsular rim stability.

Ultrastructural effects of silicone oil on the clear crystalline lens of the human eye.

PURPOSE: To evaluate light and electron microscopic changes of the anterior capsule and its epithelium after clear lens extraction of vitrectomized myopic eyes with silicone oil tamponade. METHODS: This prospective, controlled, non-randomized, interventional study included 20 anterior lens capsular specimens that were excised during combined clear lens extraction and silicone oil removal from previously vitrectomized highly myopic patients with silicone oil tamponade for previous retinal detachment surgeries. The specimens were examined via light microscopy and electron microscopy and compared with 20 anterior capsule specimens removed during clear lens extraction of non-vitrectomized highly myopic eyes. RESULTS: Light microscopic examination of clear lens anterior capsule specimens of vitrectomized myopic eyes filled with silicone oil showed relatively more flat cells with irregular outline of lens' epithelial cells with wide intercellular spaces, deeply stained nuclei, and multiple intracytoplasmic vacuoles. Scanning electron microscopy revealed collagenous surfaces filled with multiple pits, depressions, and abnormal deposits. Transmission electron microscopy revealed lens epithelial cells with apoptotic changes, many cytoplasmic vacuoles, and filopodia-like protrusions between lens epithelial cells and the capsule. Epithelial proliferation and multilayering were also observed. CONCLUSION: silicone oil may play a role in the development of apoptotic and histopathological changes in clear lens epithelial cells. Clarity of the lens at the time of silicone oil removal does not indicate an absence of cataractous changes. We found justification of combined clear lens extraction and silicone oil removal or combined phacovitrectomy when silicone oil injection is planned, but further long-term studies with larger patient groups are required.

MicroRNA-26a and -26b inhibit lens fibrosis and cataract by negatively regulating Jagged-1/Notch signaling pathway.

Fibrosis is a chronic process involving development and progression of multiple diseases in various organs and is responsible for almost half of all known deaths. Epithelial-mesenchymal transition (EMT) is the vital process in organ fibrosis. Lens is an elegant biological tool to investigate the fibrosis process because of its unique biological properties. Using gain- and loss-of-function assays, and different lens fibrosis models, here we demonstrated that microRNA (miR)-26a and miR-26b, members of the miR-26 family have key roles in EMT and fibrosis. They can significantly inhibit proliferation, migration, EMT of lens epithelial cells and lens fibrosis in vitro and in vivo. Interestingly, we revealed that the mechanisms of anti-EMT effects of miR-26a and -26b are via directly targeting Jagged-1 and suppressing Jagged-1/Notch signaling. Furthermore, we provided in vitro and in vivo evidence that Jagged-1/Notch signaling is activated in TGFß2-stimulated EMT, and blockade of Notch signaling can reverse lens epithelial cells (LECs) EMT and lens fibrosis. Given the general involvement of EMT in most fibrotic diseases, cancer metastasis and recurrence, miR-26 family and Notch pathway may have therapeutic uses in treating fibrotic diseases and cancers.

Improvement of Uveal and Capsular Biocompatibility of Hydrophobic Acrylic Intraocular Lens by Surface Grafting with 2-Methacryloyloxyethyl Phosphorylcholine-Methacrylic Acid Copolymer.

Biocompatibility of intraocular lens (IOL) is critical to vision reconstruction after cataract surgery. Foldable hydrophobic acrylic IOL is vulnerable to the adhesion of extracellular matrix proteins and cells, leading to increased incidence of postoperative inflammation and capsule opacification. To increase IOL biocompatibility, we synthesized a hydrophilic copolymer P(MPC-MAA) and grafted the copolymer onto the surface of IOL through air plasma treatment. X-ray photoelectron spectroscopy, atomic force microscopy and static water contact angle were used to characterize chemical changes, topography and hydrophilicity of the IOL surface, respectively. Quartz crystal microbalance with dissipation (QCM-D) showed that P(MPC-MAA) modified IOLs were resistant to protein adsorption. Moreover, P(MPC-MAA) modification inhibited adhesion and proliferation of lens epithelial cells (LECs) in vitro. To analyze uveal and capsular biocompatibility in vivo, we implanted the P(MPC-MAA) modified IOLs into rabbits after phacoemulsification. P(MPC-MAA) modification significantly reduced postoperative inflammation and anterior capsule opacification (ACO), and did not affect posterior capsule opacification (PCO). Collectively, our study suggests that surface modification by P(MPC-MAA) can significantly improve uveal and capsular biocompatibility of hydrophobic acrylic IOL, which could potentially benefit patients with blood-aqueous barrier damage.

Efficacy of a lutein-based dye (Phacodyne™) for visualizing anterior capsulorhexis during cataract surgery by phacoemulsification.

PURPOSE: To evaluate the efficacy and safety of a novel lutein-based dye for the anterior capsulorhexis during phacoemulsification in cataract surgery in humans. METHODS: Twenty-five eyes from 25 patients were operated by 25 different surgeons who performed continuous circular capsulorhexis (CCC) guided by a lutein-based dye (Phacodyne™) during cataract surgery by phacoemulsification. A questionnaire assessed the surgeon's opinion regarding the efficacy of the dye. Follow-up examinations were performed at 1, 7, and 30 days post-surgery. Eyes were evaluated by full ophthalmic examination, corneal topography/pachymetry, and corneal endothelial cell count. RESULTS: As revealed by the answers to the questionnaire, the dye facilitated the CCC procedure in all eyes. Baseline nuclear cataract classification (according to the Lens Opacities Classification System III; LOCS III) was 3.24 (± 1.12). Preoperative BCVA (logMAR) was 0.89 ± 0.59 and improved to 0.23 ± 0.22 on day 30 after surgery. The intraocular pressure (IOP) remained stable and the inflammatory reaction subsided in all cases within the first 7 days after surgery. The pre-operative values of corneal pachymetry and IOP were similar to those found on follow-up day 30. Loss in endothelial cell number was similar to earlier reports. CONCLUSION: Phacodyne™ was efficient when used for anterior capsulorhexis during cataract surgery by phacoemulsification and

Efficacy of a lutein-based dye (PhacodyneTM) for visualizing anterior capsulorhexis during cataract surgery by phacoemulsification / Eficácia de corante à base de luteína (PhacodyneTM) para observação da capsulorrexis anterior em cirurgia de facoemulsificação

Purpose: To evaluate the efficacy and safety of a novel lutein-based dye for the anterior capsulorhexis during phacoemulsification in cataract surgery in humans. Methods: Twenty-five eyes from 25 patients were operated by 25 different surgeons who performed continuous circular capsulorhexis (CCC) guided by a lutein-based dye (PhacodyneTM) during cataract surgery by phacoemulsification. A questionnaire assessed the surgeon's opinion regarding the efficacy of the dye. Follow-up examinations were performed at 1, 7, and 30 days post-surgery. Eyes were evaluated by full ophthalmic examination, corneal topography/pachymetry, and corneal endothelial cell count. Results: As revealed by the answers to the questionnaire, the dye facilitated the CCC procedure in all eyes. Baseline nuclear cataract classification (according to the Lens Opacities Classification System III; LOCS III) was 3.24 (± 1.12). Preoperative BCVA (logMAR) was 0.89 ± 0.59 and improved to 0.23 ± 0.22 on day 30 after surgery. The intraocular pressure (IOP) remained stable and the inflammatory reaction subsided in all cases within the first 7 days after surgery. The pre-operative values of corneal pachymetry and IOP were similar to those found on follow-up day 30. Loss in endothelial cell number was similar to earlier reports. Conclusion: PhacodyneTM was efficient when used for anterior capsulorhexis during cataract surgery by phacoemulsification and showed no signs of toxicity or side effects during the 30-day follow-up period. .

Objetivos: Avaliar a eficácia e eficiência de um novo corante à base de luteína para coloração da cápsula anterior durante cirurgia de facoemulsificação em humanos. Métodos: Vinte e cinco olhos de 25 pacientes foram operados por 25 cirurgiões diferentes que realizaram capsulorrexis circular contínua e facoemulsificação após coloração da cápsula anterior com corante à base de luteína. Um questionário avaliou a opinião dos cirurgiões sobre a eficácia do corante. Exames pós-operatórios foram realizados nos dias 1, 7 e 30 por meio de exame oftalmológico completo, topografia/ paquimetria e contagem de células endoteliais. Resultados: De acordo com o questionário aplicado, o corante facilitou a cirurgia em todos os olhos. A classificação da catarata de acordo com o LOCS III foi de 3,24 ± 1,12. A acuidade visual pré-operatória com melhor correção foi de 0,89 ± 0,59 (logMAR), passando a 0,23 ± 0,22 no pós-operatório. A pressão intraocular (PIO) permaneceu estável e houve reação de câmara leve que desapareceu em todos os casos durante os primeiros 7 dias de pós-operatório. Não houve significância estatística comparando a paquimetria e PIO pré e pós-operatórios. Conclusão: O novo corante se mostrou eficiente e sem sinais de toxicidade ou efeitos adversos, após 30 dias, quando usado para auxiliar a cirurgia de facoemulsificação. .