Lower nasal distribution of cortical cataract: the Blue Mountains Eye Study

Previous reports have indicated that cortical cataract commences in the lower nasal lens, possibly due to sunlight exposure because of the shallow brow temporally. The present study aimed to assess the lens sector distribution of cortical cataract in a population. The Blue Mountains Eye Study assessed 3654 residents aged 49–97years; 3270 phakic subjects had retroillumination lens photographs graded using the Wisconsin method, which divides the lens into eight radial sectors with a grid overlay. Graders estimated percentage of cortical opacity in each sector. The lower nasal area consistently had the greatest opacity, a pattern present at each age and similar in both sexes, despite the 20% greater cortical cataract in women. The mean area of lens cortex involved by opacities in the lower nasal hemisphere was four fold greater than in the upper temporal hemisphere at each age. The lower nasal distribution was highly symmetrical when both eyes were affected. When > 20% of the lower nasal lens quadrant had cortical opacity, 88% of bilaterally affected subjects had cortical cataract in the same quadrant of the fellow eye. The lower nasal distribution may indicate a role for sunlight in the aetiology of cortical cataract, which could be considered when examining other cortical cataract risk factors, such as diabetes, vascular disease and hormonal factors in women.     

Immunopathology of the Noninfectious Posterior and Intermediate Uveitides

The posterior and intermediate uveitides share an underlying immune etiology; however, they can be clinically and immunopathologically distinguished. Although the initiating stimuli for posterior and intermediate uveities are not known, it is believed that an exogenous agent (such as a bacterium or a virus) or an endogenous molecule may induce disease. In either case, T-helper lymphocytes in conjunction with human leukocyte antigens are likely to be involved. This review examines the epidemiology, histology, immunopathology, and theories of pathogenesis of several posterior and intermediate uveitides, including sympathetic ophthalmia, Vogt-Koyanagi-Harada syndrome, Beh?et's disease, sarcoidosis, intermediate uveitis, white dot syndromes, and birdshot retinochoroidopathy.     

A survey of local anaesthesia use in cataract surgery in Australia

A survey of the use of local anaesthesia in cataract surgery by ophthalmologists in Australia is presented. The main conclusions drawn from the survey were: 1. A marked trend towards the use of local anaesthesia in cataract surgery during the years 1983–88 throughout Australia. A less marked trend in country areas and in Western Australia. 2. The use of local anaesthesia did not correlate with the number of cataract operations performed by an ophthalmologist. 3. Day case cataract surgery was more often performed under local anaesthesia in private than in public hospitals. 4. Throughout Australia retrobulbar local anaesthesia was preferred to the peribulbar technique. 5. The most commonly used local anaesthetic mixture was 2% lignocaine and 0.5% marcaine with or without adrenaline and/or hyalase.     

CORNEAL GRAFT SURVIVAL: A RETROSPECTIVE AUSTRALIAN STUDY

Four hundred and forty-eight consecutive corneal grafts are analysed and their survival calculated usin the actuarial life-table method. Overall survival at two years is 81 ± 4% and at five years is 65 ± 5%. Within diagnostic subgroups keratoconus has the best prognosis. Previous graft failure and recipient corneal vascularization are shown to have a negative effect on graft survival. Sex of patient, urgency of operation and use of combined procedures do not affect survival and second regrafts fare no worse than first regraits. The use of the actuarial life-table method of analysing graft survival is discussed and its importance emphasized.     

Visual acuity in an Australian Aboriginal population

Background: Australia is a developed country, However; Aboriginal Australians have rates of blindness comparable to Third World countries. There have been well-funded eye health programs for 15 years in Central Australia. This paper examines if there has been an improvement in visual disability of one traditional group of Aboriginal Australians. Methods: Results from an eye health survey of the Anangu Pitjantjatjara of South Australia in 1990 are presented. These data are compared with results for ‘blindness’ and ‘poor vision’ from a national survey undertaken in 1976. The two surveys were comparable in design, both were cross-sectional population-based prevalence surveys. Prevalence rates were adjusted for the size of the source population. Results: Young rural Aboriginal Australians have good visual acuity. Low vision and blindness (WHO definitions) occur in 19.6% and 10.4% of 60+ year olds, respectively. Women were more likely than men to be blind or have low vision (OR= 1.93; 1.06-3.58). There was a decline in ‘poor vision’ between surveys (OR=2.86; 1.86-4.75) but not in ‘blindness’. Conclusion: Although there has been a reduction in the prevalence of visual disability in rural Aboriginal Australians, improvements in the provision of eye care for the elderly need to occur.     

Angle-closure glaucoma after laser treatment for retinopathy of prematurity

Laser photocoagulation has become the standard for treatment of retinopathy of prematurity. In general, it has been found to be a safe and effective means of retinal ablation. We report a case of angle-closure glaucoma in an infant after diode laser treatment for retinopathy of prematurity, which required bilateral surgical peripheral iridectomies.