Friday, May 24, 2013

Oral Glucosamine Supplements as a Possible Ocular Hypertensive Agent

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

Tuesday, May 21, 2013


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. 

Monday, May 20, 2013


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 be involved, providing additional activation of retinal dopaminergic pathways.


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.

Wednesday, May 15, 2013


Abstract in Clinical Ophthalmology:

Developmental dyslexia affects almost 10% of school-aged children and represents a significant public health problem. Its etiology is unknown. The consistent presence of phonological difficulties combined with an inability to manipulate language sounds and the grapheme–phoneme conversion is widely acknowledged. Numerous scientific studies have also documented the presence of eye movement anomalies and deficits of perception of low contrast, low spatial frequency, and high frequency temporal visual information in dyslexics. Anomalies of visual attention with short visual attention spans have also been demonstrated in a large number of cases. Spatial orientation is also affected in dyslexics who manifest a preference for spatial attention to the right. This asymmetry may be so pronounced that it leads to a veritable neglect of space on the left side. The evaluation of treatments proposed to dyslexics whether speech or oriented towards the visual anomalies remains fragmentary. The advent of new explanatory theories, notably cerebellar, magnocellular, or proprioceptive, is an incentive for ophthalmologists to enter the world of multimodal cognition given the importance of the eye's visual input.

Tuesday, May 14, 2013


This is the abstract from a study published in The British Journal of Ophthalmology

Background To analyse the relationship of clinically significant cystoid macular oedema (CME after phacoemulsification to blood–aqueous barrier breakdown as determined by aqueous flare, visual acuity and retinal thickness in optical coherence tomography (OCT).
Materials and methods 30 eyes of 30 consecutive patients with clinically significant CME and vision loss were included. 46 pseudophakic and 45 phakic eyes without CME served as controls. Clinical data included age, gender, best-corrected visual acuity (BCVA) and spectral domain OCT volume scans. Retinal thickness measuring of the foveal central subfield was determined. Aqueous flare was measured quantitatively with the Kowa FM-500 Laser Flare-Cell Meter.
Results Patients with CME had significantly higher flare values compared with pseudophakic patients (p<0 .0001="" aqueous="" bcva="" cme="" correlated="" flare="" for="" patients="" pearman="" r="" significantly="" style="border: 0px; font-family: inherit; font-size: 1em; font-style: inherit; line-height: 0; margin: 0px; outline: 0px; padding: 0px; text-align: inherit;" sub="" values="" with="">s
=0.4, p=0.041), while there was no correlation with retinal thickness. Using flare values to predict CME, receiver operating characteristic analysis returned an area under the curve of 0.976.
Conclusions Aqueous flare as a marker for inflammation and breakdown of the blood–retinal barrier is increased in patients with CME after cataract surgery.

Monday, May 13, 2013


Interesting meta-analysis in Evidence-Based Complementary and Alternative Medicine concludes:

The main findings of this meta-analysis were that effect of acupuncture treatment for amblyopia was superior to conventional treatment. However, there are several limitations to this meta-analysis...So the efficacy of acupuncture for amblyopia has not been proven beyond reasonable doubt, and further randomized controlled trials with better study methodology are needed.

Friday, May 10, 2013


According to this report from the University of Utah:

A common belief that loading up on omega-3 fatty acids may lead to less eyesight degeneration later in life has been found to be false, according to researchers. 
The National Institutes of Health’s National Eye Institute this week wrapped up a five-year study on eye disease, which concluded that omega-3 fatty acids do not reduce the risk of age-related macular degeneration.  
 Although the research rejects the presupposed benefits to eyesight derived from taking omega-3 fatty acids either in isolation, i.e. fish oil tablets, or as part of a formulated dietary  supplement, it did find that replacing beta-carotene with lutein and zeaxanthin might be helpful. 
  View the National Eye Institutes news release here.

Tuesday, May 07, 2013


This study in Rheumatology International has the following abstract:

To compare the effects of treatment with punctal plugs versus artificial tears on visual function for primary Sjögren’s syndrome with dry eye. Forty-two eyes of 42 patients with primary Sjögren’s syndrome were enrolled and were allocated randomly into artificial tears (AT) group and punctal plugs (PP) group. Ocular Surface Disease Index (OSDI) was used, and fluorescent staining for tear film break-up time (BUT), the Schirmer test I (STI) and contrast sensitivity was performed before treatment and was repeated 3 months after treatment. A follow-up of 3 months was achieved in 40 eyes of 40 patients, including 19 eyes in artificial tears group and 21 eyes in punctal plugs group. Statistically significant improvements were observed in the OSDI scores (AT: 52.6 ± 5.7, 15.9 ± 4.2; PP: 55.8 ± 4.9, 15.1 ± 4.2), corneal fluorescein staining scores (AT: 2.60 ± 1.76, 0.30 ± 0.57; PP: 1.91 ± 1.60, 0.09 ± 0.29), STI (AT: 3.85 ± 2.03, 8.95 ± 2.72; PP: 3.36 ± 1.62, 11.41 ± 2.65), and BUT (AT: 2.60 ± 1.39, 6.00 ± 1.81; PP: 2.27 ± 1.12, 7.82 ± 1.84) after treatment compared to those of pre-treatment. The values of STI (AT: 5.10 ± 1.80; PP: 8.05 ± 1.53) and BUT (AT: 3.40 ± 1.31; PP: 5.68 ± 1.13) in punctal plugs group were significantly more improved than those in the artificial tears group. The medium- and high-level frequencies contrast sensitivities were greatly improved in simulated daylight, night, and glare disability conditions after treatment with artificial tears and punctal plugs. However, the changes in contrast sensitivity did not significantly differ between groups. Both artificial tears and punctal plugs relieved dry eye symptoms, repaired corneal lesions, enhanced tear film stability, and improved contrast sensitivity. Punctal plugs could improve tear film stability and elongate the BUT better than artificial tears.

Monday, May 06, 2013


This study in Ophthalmology assessed the effect of oral omega-3 fatty acids on tear break-up time (TBUT), Schirmer's score, and Ocular Surface Disease Index (OSDI).  33 patients were randomized into the treatment group and 31 persons into the placebo group.  Sixty-four patients with dry eye symptoms between the ages of 45 and 90 years were randomized into 2 groups: 33 persons in the treatment group and 31 persons in the placebo group.
Methods: The treatment group received 2 capsules of omega-3 (each containing 180 mg eicosapentaenoic acid [EPA] and 120 mg docosahexaenoic acid [DHA]) daily for 30 days, and the placebo group received 2 medium-chain triglyceride oil capsules daily for 1 month. The outcomes were measured 1 month after the intervention.

Main Outcome Measures
The primary outcome measure was an increase from baseline in TBUT at day 30. Secondary outcome measures were a decrease from baseline in the OSDI score and an increase in the Schirmer’s score at day 30.

In the placebo group, before the intervention, the mean TBUT, OSDI, and Schirmer’s scores were 4.5 ± 2.1 seconds, 36.4 ± 13.8, and 6.0 ± 2.6 mm, respectively, and 1 month later were 4.7 ± 2.6 seconds, 37.6 ± 13.5, and 6.2 ± 2.5 mm, respectively. In the treatment group, these values were 3.9 ± 1.7 seconds, 38.7 ± 16.5, and 5.8 ± 2.5 mm before the intervention and 5.67 ± 2.6 seconds, 29.3 ± 15.9, and 6.8 ± 2.8 mm after the intervention, respectively. Repeated-measures analysis of variance showed that improvements in TBUT, OSDI, and Schirmer’s scores were significantly better in the treatment group than in the placebo group. The changes in the treatment and placebo groups were 71% and 3.3% for TBUT (P < 0.001), 26% and 4% (P=0.004) for dry eye symptoms, and 22.3% and 5.1% for Schirmer’s score (P=0.033), respectively.

This study demonstrated that oral consumption of omega-3 fatty acids (180 mg EPA and 120 mg DHA twice daily for 30 days) is associated with a decrease in the rate of tear evaporation, an improvement in dry eye symptoms, and an increase in tear secretion.


This study in Melanoma Research concluded:

The purpose of the present study was to retrospectively evaluate the safety and activity of intravenous fotemustine in patients with metastatic uveal melanoma. We report on a series of 25 consecutive patients diagnosed with metastatic uveal melanoma. Fotemustine was administered intravenously as a first-line treatment to all patients. Thrombocytopenia and leukopenia (any grade) were observed in 60 and 52% of patients, respectively. Only two patients discontinued treatment because of toxicity (G3 thrombocytopenia), whereas all other patients were discontinued for progressive disease. Two partial responses were observed. Nine patients had stable disease (disease control rate=44%). The median survival duration was 13.9 months, and the 1-year survival rate was 60%. Intravenous fotemustine is well tolerated and could improve the outcome of metastatic uveal melanoma patients with or without liver involvement, although a randomized prospective trial is required to confirm these results


This study in Clinical Ophthalmology correlates optic disc size with visual field progression in normal tension glaucoma patients. Results and conclusion were as follows:

Results: The probability of visual field stability was significantly lower in eyes with large discs (large discs showed greater progression of field defects) than in those with small discs (log rank test, P = 0.007). Progression of visual field damage was significantly associated with the optic disc area (hazard ratio [HR]: 1.812, P= 0.018), occurrence of disc hemorrhage (HR: 2.116, P = 0.028), and intraocular pressure reduction ratio (HR: 0.957, P = 0.014).
Conclusion: The optic disc area correlates with progression of visual field damage in patients with NTG.

In other words, normal tension glaucoma patients with larger disc size have a higher risk of progression of visual field defects than those with smaller disc diameters. 


This report on an analysis in Eye concluded:

This analysis strengthens the conclusions that, in patients with open-angle glaucoma or ocular hypertension, (combination Azopt 1%/Alphagan 0.2% had significantly superior IOP-lowering activity compared with either Azopt or Alphagan alone and a safety profile (20.1% adverse reaction rate) consistent with that of its individual components.

Thursday, May 02, 2013


This study reported in Diabetes Care concludes:

Patients with minimal diabetic retinopathy demonstrated more cognitive impairment than those with advanced diabetic retinopathy. Therefore, the increased prevalence of cognitive impairment in diabetes may be associated with factors other than evident retinal microvascular disease.


This study in Clinical Ophthalmology described the relationship between retinal vascular tortuosity and obstructive sleep apnea (osa).   It concludes:

 Patients with OSA have increased retinal vascular tortuosity as compared to matched controls. Increased tortuosity of the retinal vasculature may be a novel association with OSA. A larger prospective study will be necessary to further explore this relationship and its clinical significance.