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In a placebo-controlled, randomised, double-blind clinical trial, the authors evaluated the efficacy of patient-administered 1% fusidic acid viscous eye drops in clearing the commonest organisms causing pseudophakic endophthalmitis (Staphylococcus epidermidis and aureus) from the lids and conjunctivae of 79 patients before cataract surgery. The treatment group self-administered fusidic acid viscous eye drops four times daily for seven days before surgery; the placebo group received inert ophthalmic drops. Fellow eyes of both groups remained untreated as a natural control. Lower fornix and lid margin cultures were taken from both eyes before and after treatment. Before treatment, there was no statistical difference in organism counts between the groups. After treatment, eyes receiving fusidic acid were more likely to be free of clinically relevant Staphylococcus spp. than all pre-treatment eyes (for lids, P << 0.001; conjunctivae, P = 0.02). A highly significant (P < 0.001) number of lid margins were rendered 'clinically clean' (i.e., 0-49 organisms/swab) by fusidic acid when compared with untreated eyes. Treatment also effectively (P < 0.05) reduced the numbers of bacteria isolated from conjunctivae. This study indicates that there is a highly significant reduction of Staphylococcus spp. (P << 0.001), non-Staphylococcus spp. (P << 0.001) and attainment of sterile eyes (P << 0.001) at operation gained by patient self-administration of 1% fusidic acid four times daily for seven days before surgery.

Concern over potential eye injury from sunlight prompted this study to see if the levels of sunlight in Christchurch posed a particular risk to our population's eyes, whether the populace was aware of any risk and whether effective sunglasses were freely available to the public. While there has been a 4% to 9% increase in UV radiation since 1969 due to global ozone depletion, no firm evidence was found that focal ozone depletion was a particular problem in New Zealand. Christchurch residents were poorly informed about the ocular hazards of sunlight. A questionnaire completed by 200 adults disclosed 32% were unaware of the particular danger of UV light and only 3% knew that snow blindness, eclipse burns and cataracts could all be caused by sunlight. Fifty-four sunglasses were analysed for labelling and for transmission characteristics of their lenses. The standard of labelling of the sunglasses was poor with only 53% making reference to UV transmission characteristics and only three pairs stating that they adhered to the New Zealand Sunglass Standard. Attention is drawn to the need to improve public awareness of the potential for eye injury from sunlight and to improve the standard of labelling of sunglasses.

An enzyme-linked immunosorbent assay for Toxocara canis larva excretory/secretory antigen has been set up in Christchurch. Employing this test, elevated specific antibody levels for toxocara larvae were found in 3.3% (3/90) of urban adult blood donors and 4.4% (4/90) of secondary school students. In comparison, elevated levels were present in 25.6% (23/90) of New Zealand hydatid control officers. It can be concluded from the present study that the higher risk of toxocariasis experienced by hydatid officers is reflected in elevated specific antibody titres in a significant proportion of individuals when compared with controls.

Toxocara canis infects many dogs yet has been seldom implicated as a cause of human disease in New Zealand. Nine patients with diagnostic titres for Toxocara canis who were seen in Christchurch Hospital over a five-year period are described. Ophthalmoscopic signs of toxocaral infection were visible at the optic disc or posterior pole of all ten affected eyes. A localised disciform detachment of the macula or a focal granuloma on the disc or retina were the commonest lesions. Vision was reduced to 6/60 or less in five affected eyes while the remaining five eyes lost 2-4 lines of vision on the test chart.

The effectiveness of topical fusidic acid 1%, in a viscous drop base, to reduce or eliminate ocular microflora in patients undergoing cataract surgery has been studied. Forty-two patients received fusidic acid on a double-blind basis and for comparison 21 patients were similarly assessed with topical chloramphenicol. A further 17 patients received no treatment other than subconjunctival cephazolin administered to all operated eyes at the time of surgery. Quantitative bacterial counts from the conjunctivae and lash lines of each patient were made 24 hours before surgery, on the morning of operation and again 48 hours after surgery. With a regimen of five administrations on the day prior to surgery, neither topical fusidic acid 1.0% nor chloramphenicol 0.5% produced clinically or statistically significant reductions of the ocular microflora. In contrast perioperative subconjunctival cephazolin effectively reduced or eliminated lid and conjunctival microflora following surgery. This study indicates that the effectiveness of a topical antibiotic preparation for overt ocular infection cannot be directly extrapolated to the effect on resident ocular microflora, at least with short-term use for presurgical prophylaxis.