Cellular components of the idiopathic epiretinal membrane.

Idiopathic epiretinal membrane (iERM) is a fibrocellular proliferation on the inner surface of the retina, which leads to decreased visual acuity and even central visual loss. As iERM is associated to advanced age and posterior vitreous detachment, a higher prevalence is expected with increasing life expectancy and aging of the global population. Although various cell types of retinal and extra-retinal origin have been described in iERMs (Müller glial cells, astrocytes, hyalocytes, retinal pigment epithelium cells, myofibroblasts, and fibroblasts), myofibroblasts have a central role in collagen production and contractile activity. Thus, myofibroblast differentiation is considered a key event for the iERM formation and progression, and fibroblasts, Müller glial cells, hyalocytes, and retinal pigment epithelium have been identified as myofibroblast precursors. On the other side, the different cell types synthesize growth factors, cytokines, and extracellular matrix, which have a crucial role in ERM pathogenesis. In the present review, the major cellular components and their functions are summarized, and their possible roles in the iERM formation are discussed. By exploring in detail the cellular and molecular aspects of iERM, we seek to contribute for better understanding of this fibrotic disease and the origin of myofibroblasts, which may eventually drive to more targeted therapeutic approaches.

Choroidal thickness using EDI-OCT in adult-onset vitelliform macular dystrophy.

BACKGROUND: To compare choroidal thickness in patients with adult-onset foveomacular vitelliform dystrophy (AOFVD) with healthy subjects and to correlate choroidal thickness with age, gender and spherical equivalent. METHODS: A prospective, observational study of 37 eyes (15 eyes in AOFVD group and 22 eyes in control group) was conducted. Images were acquired by enhanced depth imaging optical coherence tomography (EDI-OCT). Choroidal thickness measurements were performed in the subfoveal region and at 500, 1000 and 1500 µm intervals from the foveal center to nasal and to temporal regions for subsequent averaging of values. RESULTS: The AOFVD group consisted of four male eyes (28.6 %) and 10 female eyes (71.4 %); age was 33-62 years; spherical equivalent (SE) ranged from -1.50 to 1.50 spherical diopters (SD); mean subfoveal thickness was 325.6 µm, ranging from 186 to 420 µm; and the average of thicknesses was 309.4 µm, ranging from 188 to 413 µm. The control group consisted of 12 male eyes (54.5 %) and 10 female eyes (45.5 %); age was 27-62 years; SE ranged from -2.50 to 0.50 SD; subfoveal thickness was 294.8 µm, ranging from 213 to 481 µm; and the average of thicknesses was 279.4 µm, ranging from 201 to 458 µm. CONCLUSIONS: The AOFVD group and the control group showed similar choroidal thickness by correcting for age, SE and gender. Not yet known, completely, which biochemical and vascular flow alterations of the choroid, and which functional RPE changes may play a role in the pathogenesis of this disease. EDI-OCT, incorporated in some SD-OCT devices, allows higher quality assessment of the choroid. In this article, choroidal thickness of patients with AOFVD, a rare disease with a not fully understood pathogenesis, was assessed.

In Vitro Antimicrobial Long-Term Evaluation of Corneal Preservation Media Against Microorganisms Using A Closed-Chamber Study Model.

PURPOSE: To evaluate the existence of in vitro long-term antimicrobial activity of Optisol-GS against microorganisms related to corneal infection using a closed-chamber study model. METHODS: Optisol-GS was contaminated with microorganisms related to corneal infections, and different times after contamination was analyzed using a closed-chamber study model. Microbial growths were analyzed by macroscopic observation. RESULTS: For Staphylococcus aureus and Pseudomonas aeruginosa, bacterial growth was observed in samples taken 1 hour through 7 days and 14 days after contamination occurred. For Staphylococcus epidermidis, Streptococcus agalactiae, and Candida albicans, microbial growth was observed in all samples studied. For Streptococcus pneumoniae, bacterial growth was observed in samples taken 1 hour through 72 hours after contamination. For Streptococcus pyogenes, bacterial growth was observed in samples taken 1 hour through 7 days after contamination. For Escherichia coli, bacterial growth was observed in samples taken 1 hour through 48 hours after contamination occurred. CONCLUSIONS: We conclude that no in vitro antimicrobial effect for any microorganism analyzed was observed in contaminated Optisol-GS after 72 hours; however, effective antimicrobial activity was observed for S. aureus, Str. pneumoniae, Str. pyogenes, P. aeruginosa, and E. coli after 7 to 10 days.

Antimicrobial in vitro evaluation of corneal storage media using a closed chamber study model.

PURPOSE: To evaluate in vitro the antimicrobial influence of the corneal storage media containing antibiotics using a closed chamber study model under the closest simulated environment of corneal preservation process. MATERIALS AND METHODS: Samples of cornea storage media containing streptomycin and gentamicin (Optisol-GS) were analyzed at different moments after its contamination with Staphylococcus aureus (ATCC25923). Samples were analyzed at 1, 2, 3, 4, 5, 6, 24, 48, 72 hours; 7 days; and 14 days after contamination. The samples were analyzed using a new study model system that consists of two closed coupled chambers. The upper chamber contained two culture media (chocolate agar and Sabouraud agar) and CO(2) indicator (indication of bacterial aerobic activity). The inferior chamber contained supplemented solution with an antimicrobial inhibitor. The bacterial growth parameters were analyzed by the presence or absence of bacteria in chocolate agar and by color change of CO(2) indicator when positive. First reading was performed after 24 hours, and, in the absence of bacterial growth, a second reading was carried out after 48 hours. RESULTS: Color change in CO(2) indicator was found in samples contaminated after 1, 2, and 3 hours on the first reading. On the second reading, we observed color change in all remaining samples, except for samples contaminated after 14 days. CONCLUSION: Samples of cornea storage media containing gentamicin sulphate and streptomycin sulphate in vitro showed viable Staphylococcus aureus for up to 7 days of contamination.