INTERESTING EYE NEWS & CLINICAL PEARLS

This study in Ophthalmology  concludes: When amblyopic eye VA stops improving with 2 hours of daily patching, increasing the daily patching dosage to 6 hours results in more improvement in VA after 10 weeks compared with continuing 2 hours daily.

Simbrinza is made by Alcon and is the combination of brinzolamide (Azopt) and brimonidine (Alphagan).  It is contraindicated in patients with sulfa allergies. Alcon claims that the suspension provides 1-3mmHg of additional IOP lowering affect when compared to the individual components.  Dosage is TID and because it's a suspension, it should be shaken well. 

Report in JAMA suggests oral glucosamine supplements, used for osteoarthritis, may raise intraocular pressure, leading to higher risk for glaucoma.

This study aimed to compare the 24 hour intraocular pressure control obtained with bimatoprost-timolol fixed combination (Ganfort) vs. latanoprost in newly diagnosed, previously untreated patients with exfoliative glaucoma patients with baseline IOP greater than 29mmHg.  It concludes: As first choice therapy in high-pressure, at-risk exfoliation patients, bimatoprost-timolol controlled mean 24 hour intraocular pressure significantly better than latanoprost monotherapy. 

According to this study in Ophthalmology : The corneal hysteresis (CH) measurements were significantly associated with risk of glaucoma progression. Eyes with lower CH had faster rates of visual field loss than those with higher CH. The prospective longitudinal design of this study supports the role of CH as an important factor to be considered in the assessment of the risk of progression in patients with glaucoma.

This is the abstract from a study in Experimental Eye Research : Recent epidemiological evidence in children indicates that time spent outdoors is protective against myopia. Studies in animal models (chick, macaque, tree shrew) have found that light levels (similar to being in the shade outdoors) that are mildly elevated compared to indoor levels, slow form-deprivation myopia and (in chick and tree shrew) lens-induced myopia. Normal chicks raised in low light levels (50 lux) with a circadian light on/off cycle often develop spontaneous myopia. We propose a model in which the ambient illuminance levels produce a continuum of effects on normal refractive development and the response to myopiagenic stimuli such that low light levels favor myopia development and elevated levels are protective. Among possible mechanisms, elevation of retinal dopamine activity seems the most likely. Inputs from intrinsically-photosensitive retinal ganglion cells (ipRGCs) at elevated light levels may b...

This study in the Journal of Cornea and External Disease determined whether or not chalazion affects refractive error.  It concludes:  Chalazion increases higher-order aberrations, as measured by the Hartmann–Shack aberrometer, which could affect the preoperative evaluation and results of refractive surgery, especially wavefront-guided approaches. Chalazion excision could reduce ocular aberrations and is recommended before refractive surgeries. My personal experience is the same with dermatochalasis. That means we should delay corrective refraction if a person is considering surgery.