Nutritional supplement use and age-related macular degeneration

Age-related macular degeneration is one of the leading causes of visual loss among people aged 65 years or older. The causes and factors associated with the progression of age-related macular degeneration are unknown presently. Basic research and epidemiologic data support the hypotheses that higher levels of antioxidant vitamins and minerals may protect the eye from the development of age-related macular degeneration. For this reason and also because of the lack of effective treatment for most cases of age-related macular degeneration, nutritional supplements with antioxidants have emerged as possible therapy for age-related macular degeneration. Nutritional supplements are not proven therapy for age-related macular degeneration. The potential beneficial effects and adverse side effects of the nutritional supplements have not yet been fully evaluated in carefully conducted clinical trials. Several randomized placebo-controlled clinical trials are presently underway. Results of these studies will provide important data to clarify the potential beneficial and adverse effects of such treatment. Until these results are available, it would be premature to make recommendations in favor of vitamin or mineral supplements.     

Prospective cohort study of antioxidant vitamin supplement use and the risk of age-related maculopathy

In a prospective cohort study, the authors examined whether self-selection for antioxidant vitamin supplement use affects the incidence of age-related maculopathy. The study population consisted of 21,120 US male physician participants in the Physicians' Health Study I who did not have a diagnosis of age-related maculopathy at baseline (1982). During an average of 12.5 person-years of follow-up, a total of 279 incident cases of age-related maculopathy with vision loss to 20/30 or worse were confirmed by medical record review. In multivariate analysis, as compared with nonusers of supplements, persons who used vitamin E supplements had a possible but nonsignificant 13% reduced risk of age-related maculopathy (relative risk = 0.87, 95 percent confidence interval (CI) 0.53-1.43), while users of multivitamins had a possible but nonsignificant 10% reduced risk (relative risk = 0.90, 95% CI 0.68-1.19). Users of vitamin C supplements had a relative risk of 1.03 (95% CI 0.71-1.50). These observational data suggest that among persons who self-select for supplemental use of antioxidant vitamin C or E or multivitamins, large reductions in the risk of age-related maculopathy are unlikely. Randomized trial data are accumulating to enable reliable detection of the existence of more plausible small-to-moderate benefits of these agents alone and in combination on age-related maculopathy.     

Calcium oxalate urolithiasis in cats

Urolithiasis has long been recognized as a cause of irritative voiding in cats. Before the late 1980s, sterile struvite was the most common urolith; today, however, 40% of feline uroliths are of calcium oxalate. This change may be partly attributable to the change to urine-acidifying, magnesium-restricted diets that were introduced to reduce the formation of struvite. However, it is possible that the diet modifications made by cat food manufacturers simply exposed a population of cats predisposed to calcium oxalate stone formation. Urolithiasis in cats appears to be diet sensitive rather than diet induced. As in humans, water is crucial in the prevention and treatment of feline stones.     

Post-steroid elevations of intraocular pressure in patient after radial keratotomy

PURPOSE: The evaluation of frequency and amplitude of IOP elevations in patients after RK who were administrated topically dexamethasone. MATERIAL AND METHODS: RK was carried out in 90 eyes (55 patients). All these patients had been treated topically with 0.1% dexamethasone (Maxitrol, Alcon) since the first day after surgery till the period of 3 months in lowering doses. IOP was measured using air-puff tonometer (Reichert, USA) before surgery and on 1, 2, 3, 14, 30, 50, 90 day after RK. In case of IOP elevations the measurements were made more often. RESULTS: The mean IOP before surgery was 14.88 +/- 2.86 mm Hg for women and 16.14 +/- 2.83 mm Hg for men. In the period of 3 months after RK maximum IOP increased significantly both for women (mean: 21.46 +/- 7.51 mm Hg) and men (mean: 26.14 +/- 8.87 mm Hg). IOP higher than 25 mm Hg was observed in 35 eyes (37.7%). These IOP elevations were observed more often in men than women but this difference was not statistically significant. There was no correlation between frequency of IOP elevations and preoperative refractive error or the age of patients. CONCLUSIONS: The usage of steroids after RK requires careful monitoring of IOP. This subject needs further studies to answer if these IOP elevations can damage eye functions.     

Radiation exposure: a new risk factor for idiopathic perifoveal telangiectasis

Objective

To examine the association between previous radiation exposure and idiopathic perifoveal telangiectasis (IPT).

Analysis of the place of regulation of C-11 transmitters at the Tele-electronic Works "Telkom-Telfa" in Bydgoszcz from the point of view of visual hygiene]

The authors performed a detailed analysis of 100 positions of regulation of the C-11 transmitters in the "Telcom-Telfa" ++Tele-electronic Works in Bydgoszcz. It was determined that the requirements for the condition of the eyes and the lighting at this workstand are considerable. Conclusions and recommendations tending to improvement of the working conditions are drawn up. Proposed is eventual rationale leading to the reduction of the eyestrain and facilitation of the work.     

Paraneoplastic optic neuropathy in nasopharyngeal carcinoma--report of a case

A 31-year-old Chinese man developed left optic neuritis with left sectorial field loss as a remote effect of nasopharyngeal carcinoma. The field defect showed interesting fluctuations in response to the dosage of systemic steroid therapy. Neuropathologic findings from an exploratory craniotomy did not show any gross tumour mass around the left optic nerve nor any histological evidence of tumour infiltration. This case illustrates that "optic neuritis" could be a paraneoplastic effect of nasopharyngeal carcinoma.