Hyperbaric oxygen in the treatment of acute retinal artery occlusion.

INTRODUCTION: Acute retinal artery occlusion (ARAO) is a major cause of sudden, painless visual loss, often leaving no useful vision in the affected eye. Its incidence is cited at 0.85 per 100,000 persons per year but may be higher because of under-reporting. The natural history is difficult to study, but a spontaneous resolution rate of < 1-8% for acute, non-arteritic ARAO has been cited. Occurrence in an only eye is devastating for the patient. There is currently no consensus regarding management of ARAO and little evidence to support any treatment modality. Despite only limited case series, hyperbaric oxygen treatment (HBOT) is recommended for ARAO by the Undersea and Hyperbaric Medical Society (UHMS) and by the European Committee for Hyperbaric Medicine. METHODS: Between early 2003 and December 2012, all ARAO patients presenting to Christchurch Hospital were referred for consideration of HBOT. These 31 consecutive patients' medical records were reviewed retrospectively. The time delay from onset of visual loss to commencing HBOT; the presenting visual acuity; various demographic data; the HBOT administered and the outcome visual acuity were documented. RESULTS: All 31 patients underwent at least one HBOT (median 4, range 1-7) at a pressure of 203-284 kPa for 1.5 to 2.0 h. One patient's treatment was terminated after 60 min at their request; another declined further HBOT and one suffered middle ear barotrauma. Thirteen patients also received anticoagulants at the discretion of the referring ophthalmologist. Twenty three patients had temporarily improved vision with the first HBOT. Seven patients had permanent, good visual recovery (6/18 or better; Snellen chart); and two only modest improvement (6/60). All nine patients who improved permanently were treated within 10 hours of symptom onset. CONCLUSIONS: Where available, HBOT is indicated for ARAO. Our protocol may not have been aggressive enough and the UHMS protocol is recommended. A multi-centre, randomised controlled trial is feasible, but would be logistically difficult and expensive and may be ethically unsupportable given the lack of alternative, effective treatments.

Dietary supplement use in the prevention of age-related macular degeneration progression.

PURPOSE: The Age-Related Eye Disease Study Group (AREDS) has found high-dose vitamin supplementation may have a role in preventing the progression of Category 3 and 4 age-related maculopathy. The aim of this study is to compare dietary antioxidant, zinc, and copper intakes of Australia, New Zealand, United Kingdom, and the United States to determine the difference between the actual and suggested AREDS intakes for these nutrients. A further aim is to investigate the constituents of commonly available single and multivitamin preparations in New Zealand and carry out a cost analysis. METHODS: The total median intake of vitamins A, C, and E; zinc; and copper is analysed from the most recent nutrition data published by the four countries. Forty multivitamin brands and 32 individual nutrient brands were analysed. An average price per tablet for each brand has been calculated in New Zealand dollars. RESULTS: The median intakes of antioxidants, zinc, and copper for these countries were comparable, but lower than the AREDS suggested intakes. Sixteen of the 40 multivitamin preparations contained all recommended nutrients. Of these, only two fulfilled the AREDS-recommended levels. The cost of different preparations is similar. CONCLUSION: Dietary supplementation is required to achieve the AREDS nutrient intake recommendations. This may be achieved by using any combination of multivitamin and individual supplement preparations available. Comprehensive tables have been constructed to guide ophthalmologists in the process of suggesting supplementation to prevent the progression of Category 3 and 4 age-related maculopathy.

A systematic review of the applicability and efficacy of eye exercises.

PURPOSE: To examine the current scientific evidence base regarding the efficacy of eye exercises as used in optometric vision therapy. METHODS: A search was performed of the following databases: Allied and Complementary Medicine Database, Cochrane Database of Systematic Reviews, Cochrane Register of Controlled Trials, EMBASE, and MEDLINE. Relevant articles were reviewed and analyzed for strengths and weaknesses. Pertinent sections of classic texts were studied to provide a historical basis and to serve as a source for additional early references. RESULTS: Forty-three refereed studies were obtained. Of these, 14 were clinical trials (10 controlled studies), 18 review articles, 2 historical articles, 1 case report, 6 editorials or letters, and 2 position statements from professional colleges. Many of the references listed by the larger reviews were unpublished or published in obscure or nonrefereed sources and therefore were not accessible. CONCLUSIONS: Eye exercises have been purported to improve a wide range of conditions including vergence problems, ocular motility disorders, accommodative dysfunction, amblyopia, learning disabilities, dyslexia, asthenopia, myopia, motion sickness, sports performance, stereopsis, visual field defects, visual acuity, and general well-being. Small controlled trials and a large number of cases support the treatment of convergence insufficiency. Less robust, but believable, evidence indicates visual training may be useful in developing fine stereoscopic skills and improving visual field remnants after brain damage. As yet there is no clear scientific evidence published in the mainstream literature supporting the use of eye exercises in the remainder of the areas reviewed, and their use therefore remains controversial.