Enhanced depth imaging optical coherence tomography of the optic nerve head improves correct diagnosis in glaucoma suspects without glaucomatous optic disc morphology.

An 83-year-old woman with a long history of glaucoma and optic disc drusen (ODD) was referred for neuro-ophthalmological second opinion. The patient had been treated for decades with bilateral intraocular pressure (IOP)-lowering eye drops, laser trabeculoplasty and trabeculectomy and had severe, bilateral loss of visual fields and retinal nerve fibre layer (RNFL) thinning on optical coherence tomography (OCT) despite IOP that never exceeded 24 mm Hg. On ophthalmoscopy, only a single ODD was visible in the left eye and no optic disc cupping was apparent in either eye. Enhanced depth imaging OCT (EDI-OCT) of the optic nerve head revealed bilateral multiple, large, deep ODD, which in itself could easily explain the visual field loss and RNFL thinning of this patient. Optic nerve head examination using EDI-OCT is highly recommended for patients with a history of glaucoma but without optic nerve head cupping to avoid a potential misdiagnosis with consequent unnecessary treatment.

Povidone iodine treatment is deleterious to human ocular surface conjunctival cells in culture.

OBJECTIVE: To determine the effect of povidone iodine (PI), an antiseptic commonly used prior to ocular surgery, on viability of mixed populations of conjunctival stratified squamous and goblet cells, purified conjunctival goblet cells and purified conjunctival stromal fibroblasts in primary culture. METHODS AND ANALYSIS: Mixed population of epithelial cells (stratified squamous and goblet cells), goblet cells and fibroblasts were grown in culture from pieces of human conjunctiva using either supplemented DMEM/F12 or RPMI. Cell type was evaluated by immunofluorescence microscopy. Cells were treated for 5 min with phosphate-buffered saline (PBS); 0.25%, 2.5%, 5% or 10% PI in PBS; or a positive control of 30% H2O2. Cell viability was determined using Alamar Blue fluorescence and a live/dead kit using calcein/AM and ethidium homodimer-1 (EH-1). RESULTS: Mixed populations of epithelial cells, goblet cells and fibroblasts were characterised by immunofluorescence microscopy. As determined with Alamar Blue fluorescence, all concentrations of PI significantly decreased the number of cells from all three preparation types compared with PBS. As determined by calcein/EH-1 viability test, mixed populations of cells and fibroblasts were less sensitive to PI treatment than goblet cells. All concentrations of PI, except for 0.25% used with goblet cells, substantially increased the number of dead cells for all cell populations. The H2O2 control also significantly decreased the number and viability of all three types of cells in both tests. CONCLUSION: We conclude that PI, which is commonly used prior to ocular surgeries, is detrimental to human conjunctival stratified squamous cells, goblet cells and fibroblasts in culture.

[Should ophtalmologists recommend medical cannabis to patients with glaucoma?]

Cannabis has been widely used for various medical purposes since before year 2000 BC. Its effects are mediated by cannabinoids and stimulation of mainly G-protein coupled cannabinoid receptors. In 1971, subjects who smoked marihuana, showed a decrease in the intraocular pressure. Later investigations additionally revealed a neuroprotective effect of both ∆-9-tetrahydrocannabinol and cannabidiol (CBD). Furthermore, CBD was found to promote neurogenesis. The aim of this review is to provide an overview of the potential use of cannabinoids in the treatment of glaucoma.

Essential Roles of Lactate in Müller Cell Survival and Function.

Müller cells are pivotal in sustaining retinal ganglion cells, and an intact energy metabolism is essential for upholding Müller cell functions. The present study aimed to investigate the impact of lactate on Müller cell survival and function. Primary mice Müller cells and human Müller cell lines (MIO-M1) were treated with or without lactate (10 or 20 mM) for 2 and 24 hours. Simultaneously, Müller cells were incubated with or without 6 mM of glucose. L-lactate exposure increased Müller cell survival independently of the presence of glucose. This effect was abolished by the addition of the monocarboxylate inhibitor 4-cinnamic acid to the treatment media, whereas survival continued to increase in response to addition of D-lactate during glucose restriction. ATP levels decreased over time in MIO-M1 cells and remained stable over time in primary Müller cells. Lactate was preferably metabolized in MIO-M1 cells compared to glucose, and 10 mM of L-Lactate exposure prevented complete glycogen depletion in MIO-M1 cells. Glutamate uptake increased after 2 hours and decreased after 24 hours in glucose-restricted Müller cells compared to cells with glucose supplement. The addition of 10 mM of lactate to the treatment media increased glutamate uptake in glucose supplemented and restricted cells. In conclusion, lactate is a key component in maintaining Müller cell survival and function. Hence, lactate administration may be of great future interest, ultimately leading to novel therapies to rescue retinal ganglion cells.