Effect of a hyaluronic acid and carboxymethylcellulose ophthalmic solution on ocular comfort and tear-film instability after cataract surgery.

PURPOSE: To evaluate the efficacy and safety of using sodium hyaluronate 0.1% and carboxymethylcellulose 0.5% artificial tears for ocular discomfort and tear-film stability in eyes after cataract surgery. SETTING: Twenty ophthalmic centers in Italy. DESIGN: Prospective randomized case series. METHODS: This study enrolled patients scheduled for unilateral cataract surgery. After surgery, patients received artificial tears and a topical steroid-antibiotic (study group) or topical steroid-antibiotic alone (control group) and were assessed postoperatively at 1 and 5 weeks. Outcome measures were tear breakup time (TBUT), ocular surface disease index (OSDI), frequency of dry-eye symptoms evaluated using a visual analog scale (VAS), and corneal fluorescein staining. RESULTS: The study comprised 282 patients. At 5 weeks, the mean TBUT was statistically significantly higher in the study group than in the control group (P = .0003). The mean OSDI score statistically significantly improved in both groups from 1 to 5 weeks (P < .0001 for both groups); however, there was no statistically significant difference between the groups at these timepoints. The artificial tears statistically significantly improved VAS-assessed dry-eye symptoms in the study group compared with the control group at 5 weeks (P < .001). The mean corneal fluorescein staining was significantly reduced in the study group compared with the control group at 5 weeks (P = .002 versus P = .05, respectively). No treatment-related adverse events were reported. CONCLUSION: Sodium hyaluronate 0.1% and carboxymethylcellulose 0.5% ophthalmic solution was effective and well tolerated in reducing dry-eye disease symptoms and improving the clinical outcome after cataract surgery. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Square-edge intraocular lenses and epithelial lens cell proliferation: implications on posterior capsule opacification in an in vitro model.

BACKGROUND: To evaluate lens epithelial cell (LEC) proliferation with two different designs (one-piece or three-piece) of hydrophobic acrylic IOLs with 360° square optic edge using an in vitro culture model of posterior capsule opacification (PCO). METHODS: This experimental study was conducted at the Department of NEUROFARBA, Section of Pharmacology, University of Florence, Italy. Human LECs were seeded and cultured in transwell cell culture inserts coated with a type-IV collagen membrane on which an IOL (one-piece Tecnis-1 or three-piece AR40E, Abbott Medical Optics Inc.) had been previously placed. As control, cells were plated on the insert membrane without an IOL. At day six (cells confluent in controls) IOLs were removed and cell counting, viability and cell density under and outside the IOLs were evaluated. RESULTS: No statistically significant difference in the number of cells (p>0.05) between inserts with the one-piece and three-piece IOLs was found. Cell density in the area under each IOL was significantly lower than in the area outside of it (p<0.05), or in the control insert. (p<0.05). Cell density under the single-piece IOL was not significantly different from that under the three-piece IOL (p>0.05). CONCLUSIONS: A 360° sharp-edge played a crucial role in avoiding LEC migration under the IOL and preventing the formation of PCO after cataract surgery. Long term clinical evaluation is necessary to estimate functional results.

Early effects of corneal collagen cross-linking by iontophoresis in ex vivo human corneas.

PURPOSE: The purpose was to investigate the early modifications induced by collagen cross-linking by iontophoresis of riboflavin (ionto-CXL) in ex vivo human corneas by evaluating different protocols of UVA irradiation. METHODS: In this experimental study 46 ex vivo human corneas obtained from the Eye Bank of Mestre (Italy) were divided in different groups: six were utilized as control (CTL); eight were treated with ionto-CXL at 3 mW/cm(2) power for 30 min (I-3); eight were treated with ionto-CXL at 10 mW/cm(2) for 9 min (I-10); eight were treated with iontophoretic delivery of riboflavin only (I-0); eight were treated with the standard CXL at 3 mW/cm(2) for 30 min (S-3); and eight were treated with CXL at 10 mW/cm(2) for 9 min (S-10). All samples were evaluated by haematoxylin-eosin staining and immunohistochemical analysis using different markers (Connexin 43, CD34, Collagen I, TUNEL assay). Western blot analysis, utilizing Bax and Ki67 primary antibodies, for detection of keratocyte apoptosis and proliferation, respectively, was also performed. RESULTS: No endothelial damage was evidenced in the treated groups. In I-10 corneas the epithelial layers were not always well-preserved. Anterior stroma showed an uneven distribution and numerical reduction of keratocytes as well as increased apoptosis; a reduced subepithelial interweaving of collagen I fibers was observed. In S-3 and S-10 the changes induced by treatments were similar to I-10. I-3 and I-0 showed no significant changes with respect to the control group. CONCLUSIONS: In the ionto-CXL at 10 mW/cm(2) group occurred the main morphological and biomolecular changes. This experimental study suggests that iontophoresis can be considered a non-invasive potential delivery tool for riboflavin penetration in corneal stroma during CXL.

CoQ10-containing eye drops prevent UVB-induced cornea cell damage and increase cornea wound healing by preserving mitochondrial function.

PURPOSE: We evaluated the potential protective effects of Coenzyme Q10 (CoQ10) on human corneal cells and rabbit eyes after ultraviolet B (UVB) exposure and a model of wound healing in rabbit eyes after corneal epithelium removal. METHODS: Human corneal epithelium cells (HCE) were exposed to a source of UVB radiation (312 nM) in the presence of different CoQ10 concentrations or vehicle. The mitochondrial function and cell survival were evaluated by means of 3-(4,5-dimethylthiazole-2-yl)2,5-diphenyl-tetrazolium (MTT) reduction and lactic dehydrogenase (LDH) release. Furthermore, quantitation of oxygen consumption and mitochondrial membrane potential were conducted. In vivo rabbit models were adopted to evaluate the effect of CoQ10 on UVB-induced conjunctival vessel hyperemia and corneal recovery after ethanol induced corneal lesion. RESULTS: In UVB-exposed HCE cells, CoQ10 addition led to an increased survival rate and mitochondrial function. Furthermore, oxygen consumption was maintained at control levels and adenosine triphosphate (ATP) decline was completely prevented in the CoQ10-treated cells. Interestingly, in an in vivo model, CoQ10 was able dose-dependently to reduce UVB-induced vessel hyperemia. Finally, in a model of corneal epithelium removal, 12 hours from surgery, animals treated with CoQ10 showed a reduction of damaged area in respect to vehicle controls, which lasted until 48 hours. CONCLUSIONS: We demonstrated that CoQ10 reduces corneal damages after UVB exposure in vivo and in vitro by preserving mitochondrial function. Also, for the first time to our knowledge we showed that the administration of CoQ10 after corneal epithelium removal promotes corneal wound healing.