METHODS: The Bovine Corneal Opacity and Permeability test method (BCOP), OECD Test Guideline 437, was used as an initial step to study the inducing effect of palm-based MES on irreversible eye damage. The second assessment involved the use of reconstructed human corneal-like epithelium test method, OECD Test Guideline 492 using SkinEthic™ Human Corneal Epithelium to study the potential effect of palm-based MES on eye irritancy. The palm-based MES were prepared in 10% solution (w/v) in deionized water and tested as a liquid and surfactant test substances whereby both test conducted according to the liquid/surfactant treatment protocol.
RESULTS: The preliminary BCOP results showed that palm-based MES; C12, C14, C16, C16:18 were not classified as severe eye irritants test substances with in vitro irritancy score between 3 and the threshold level of 55. The second evaluation using SkinEthic™ HCE model showed that palm-based MES; C12, C14, C16, C16:18 and three commercial samples were potentially irritants to the eyes with mean tissue viability ≤ 60% and classified as Category 2 according to United Nations Globally Harmonized System of Classification and Labelling of Chemicals. However, there are some limitations of the proposed ocular irritation classification of palm-based MES due to insolubility of long chain MES in 10% solution (w/v) in deionized water.
CONCLUSION: Therefore, future studies to clarify the eye irritation potential of the palm-based MES will be needed, and could include; methods to improve the test substance solubility, use of test protocol for solids, and/or inclusion of a benchmark anionic surfactant, such as sodium dodecyl sulphate within the study design.
METHODS: We investigated the ocular permeation of topical tazocin after single drop application in normal rabbit eyes by estimating piperacillin and tazobactam concentrations in cornea, aqueous, and vitreous using a validated LC-MS/MS method. Furthermore, we determined the efficacy of repeated dose administration of tazocin against experimentally induced P. aeruginosa keratitis in rabbits in comparison to moxifloxacin. To determine the efficacy, clinical examination, histopathological examination, and estimation of bacterial load and inflammatory cytokines in cornea were done.
RESULTS: Significant corneal concentration of piperacillin and tazobactam was detected in normal rabbit corneas after single dose treatment with tazocin. In rabbits with Pseudomonas-induced keratitis, topical tazocin caused significant clinical and histopathological improvement. This improvement was associated with reduction in corneal bacterial load and inflammatory cytokines. Compared to moxifloxacin 0.5%, tazocin treated group showed greater clinical response which was associated with higher interleukin (IL)-1β, lower tumor necrosis factor (TNF)-α, a comparable level of IL-8, greater reduction in corneal bacterial load, and lesser inflammatory cell infiltration.
CONCLUSION: Tazocin showed good ocular penetration and was effective in treatment of Pseudomonas induced keratitis in rabbits.
METHODS: The records of 126 eyes from 54 male and 72 female eyes were studied retrospectively, ranging from 6 months to 3 years post-PRK. Refractive errors ranged from low to high myopia and astigmatism, and proper and careful preoperative selection of patients was made. A single standard ablation zone (AZ) of 6.00 mm and transition zone (TZ) of 7.00 mm was made in all cases.
RESULTS: The study population showed a high degree of accuracy in visual outcome. In simple myopia, 92.3% of female eyes and 84.1% of male eyes had a visual acuity of more than 6/9 or better. In myopia with astigmatism, 83.05% of female and 65.9% of male eyes had a visual acuity of 6/9 (20/40) or better. However, despite the residual myopia, whether with or induced astigmatism, post PRK visual acuity seemed to be less influenced by it, than as in the pre-PRK status.
CONCLUSION: This study showed an accuracy in visual outcome of > 90% for females and > 80% for males. The Nidek EC-500 was satisfactory for its purpose.
METHODS: A 45-year-old man who had undergone LASIK 5 years previously presented with blurred distance vision. Unaided vision in the right eye was 20/329-2) and 20/20 in the left eye. He enrolled for NeuroVision treatment (NeuroVision Pte Ltd, Singapore), a computer-based interface in which a repetitive set of visual excerises is performed for 10 to 12 weeks.
RESULTS: After 35 sessions, unaided visual acuity in the right eye was 20/16(-3) and 20/20(-1) in the left eye, representing 2.8 lines of improvement in the right eye and 1.6 lines in the left eye.
CONCLUSIONS: NeuroVision, a noninvasive treatment based on the concept of perceptual learning, is a benefit in cases in which surgical enhancement is not recommended.
DESIGN: A single-center, randomized controlled trial.
METHODS: A total of 132 patients with uncomplicated phacoemulsification were randomly allocated to the intervention or control group. The intervention group received postoperative eye patching for approximately 18 hours, whereas the control group received eye shield. The clear corneal incision architecture was examined postoperatively at 2 hours, 1 day, and 7 days after surgery using optical coherence tomography.
RESULTS: Epithelial gaping was significantly reduced on postoperative day 1 in the intervention group (52.4%) compared with control (74.2%) (P = 0.01). No differences were found for other architectural defects. Descemet membrane detachment was associated with lower intraocular pressure on postoperative day 7 (P = 0.02). Presence of underlying diabetes mellitus did not seem to influence architectural defects.
CONCLUSIONS: Postoperative eye patching facilitated epithelial healing and reduced the occurrence of epithelial gaping on postoperative day 1. It may play a role in protecting and improving corneal wounds during the critical immediate postoperative period.
METHODS: Stromal derived corneal fibroblasts from New Zealand White rabbit (n = 6) were isolated and cultured until passage 1. In vitro corneal ulcer was created using a 4 mm corneal trephine onto confluent cultures and treated with basal medium (FD), medium containing serum (FDS), with and without 0.025 % AH. Wound areas were recorded at day 0, 3 and 6 post wound creation. Genes and proteins associated with wound healing and differentiation such as aldehyde dehydrogenase (ALDH), vimentin, alpha-smooth muscle actin (α-SMA), collagen type I, lumican and matrix metalloproteinase 12 (MMP12) were evaluated using qRT-PCR and immunocytochemistry respectively.
RESULTS: Cells cultured with AH-enriched FDS media achieved complete wound closure at day 6 post wound creation. The cells cultured in AH-enriched FDS media increased the expression of vimentin, collagen type I and lumican genes and decreased the ALDH, α-SMA and MMP12 gene expressions. Protein expression of ALDH, vimentin and α-SMA were in accordance with the gene expression analyses.
CONCLUSION: These results demonstrated AH accelerate corneal fibroblasts migration and differentiation of the in vitro corneal ulcer model while increasing the genes and proteins associated with stromal wound healing.
OBJECTIVE: To report two cases of malignant melanoma in the eye, one in the conjunctiva and the other in the choroid.
CASES: The first case was in a 49-year-old lady who presented with a swelling on the inner side of left upper eyelid. The vision was 6/6. On everting the eyelid, multiple, pigmented, nodular swellings were noted on the tarsal conjunctiva. Excision biopsy confirmed the diagnosis of malignant melanoma of the conjunctiva. A pigmented nodular swelling occurred on the lower bulbar conjunctiva in the same eye one-and-a-half years after the first presentation. There were no secondary nodules in the body. Excision biopsy confirmed malignant melanoma of the conjunctiva. The second case was in a 72-year-old lady who presented with pain and bleeding in the right eye. There was no perception of light. The cornea was hazy and the details behind it could not be seen. There was micro perforation of the cornea with oozing of blood and secondary glaucoma. B-scan ultrasonography of the right eye revealed an intraocular tumour. The histopathology of the enucleated eyeball confirmed the diagnosis of malignant melanoma of the choroid.
CONCLUSION: In the case of conjunctival melanoma, the occurrence of tumour at multiple sites and absence of recurrence at the original site suggests the possibility of de novo origin of the tumour. Secondary glaucoma and bleeding may be the presenting features of melanoma in the choroid.