Glaucoma screening by optometrists: positive predictive value of visual field testing

PURPOSE

Visual field testing is increasingly being performed by optometrists in order to improve glaucoma detection. The aim of this study was to assess the positive predictive value (PPV) of visual field testing as currently practised by optometrists.

METHODS

A retrospective study was performed of referrals for suspected glaucoma to an ophthalmology department during a 3 month period. The PPV for glaucoma was determined according to the reason for referral.

RESULTS

There were 86 referrals for suspected glaucoma. Isolated field loss accounted for 12% of these referrals but no cases of glaucoma detection. These subjects were either false positive referrals or had field defects of nonglaucomatous aetiology (tilted optic disc and porencephalic cyst). The PPV for glaucoma among referrals with isolated field loss was significantly less than that among referrals with field loss in association with corroborative abnormalities (0 vs. 60%, p = 0.005). No such difference was found for referrals with raised intraocular pressure (43% vs. 57%, p = 0.38) or suspicious discs (25% vs. 53%, p = 0.60).

CONCLUSIONS

Visual field testing is currently leading to unnecessary referrals to the hospital eye service with no detectable improvement in the accuracy of glaucoma suspect referrals. It is important that optometrists perform visual field testing in accordance with validated screening methodology.

Knowledge, attitudes, beliefs, and practices about HIV/AIDS in Kuwait

This survey is aimed at assessing knowledge, attitudes, beliefs and practices in Kuwait regarding AIDS/HIV. Structured face-to-face interviews were conducted during the year 1995 on a sample of 2,219 subjects, aged 18 to 60, health professionals were excluded. The survey instrument included 26 questions on AIDS/HIV knowledge, 6 about attitudes and beliefs, and 6 about behavior and practice. The remaining 22 items dealt with sociodemographic characteristics, role of religion, source of information, and satisfaction about AIDS control programs. Two thirds of subjects had good knowledge about the main modes of HIV/AIDS transmission. Using a multiple regression model, the knowledge score was positively associated with level of education, age, years of hearing about AIDS, and socioeconomic status. The multiple logistic regression showed that subjects tend not to change their behavior related to AIDS if they were less than 40 years old, had low education, were females, single, had a lower socioeconomic status, had heard about AIDS for less than 3 years, and had a low level of knowledge about AIDS. More than half of the participants were satisfied with the government's action for AIDS prevention. The majority of subjects thought that religion was important in dealing with daily life problems. In conclusion, while most of the people in Kuwait were aware of the main modes of AIDS transmission, a gap existed about modes that did not transmit the disease. This was reflected in their attitudes and practice toward AIDS patients. The study calls for a greater role for medical professionals, mass media, and religion in AIDS prevention and control.

Screening for colorectal cancer: present, past and future

Colorectal cancer results in 18,000 deaths annually in England and Wales, with 24,000 new cases diagnosed each year. Despite a better understanding of the genetics, and advancement in surgical and anaesthetic techniques, there has been little reduction in mortality and morbidity from this disease over the past 25 years. Colorectal cancer fits recognized criteria for a disease that should be screened in asymptomatic individuals. The putative duration of the adenoma to carcinoma sequence gives an ample window of opportunity to detect and treat colorectal cancer. In this article we have reviewed the strategies involved in screening for colorectal cancer in an asymptomatic population. We have presented trials and arguments for and against the different screening methods and discussed cost effectiveness of screening. In the USA and Canada, major professional organizations and societies now endorse screening; in the UK it is still far from being accepted. We feel that the available evidence shows that colorectal cancer screening has the potential to reduce the morbidity and mortality from this disease and that funding for a mass screening and public education programme should be sought.

Visceral afferent pathways to the thalamus and olfactory tubercle: behavioral implications

The goal of this study was to support the hypothesis that visceral signals may integrate and influence behavior by way of direct pathways from the nucleus tractus solitarii (NTS) to the olfactory tubercle and the midline/intralaminar thalamus. An anterograde tracer, biotinylated dextran amine (BDA) was iontophoresed bilaterally into the caudal NTS to optimize terminal labeling. NTS-cortical projections traversed both limbs of the diagonal bands providing heavy innervation, and terminated lightly within layer 3 of the olfactory tubercle. NTS-thalamic projections terminated within anterior and, as previously shown, posterior divisions of nucleus paraventricularis thalami and avoided the adjoining mediodorsal thalamic nucleus. Heretofore unrecognized projections were traced to the parafascicular and reuniens thalamic nuclei, and the peripeduncular nucleus. Control experiments identified the nucleus gracilis as the principal source of ascending projections to ventroposterior lateral, posterior and intralaminar thalamic nuclei. Our data corroborate the supposition that olfactory signals may integrate with visceral stimuli in the striatal compartment of olfactory tubercle. NTS projections encompass thalamic nuclei that project topographically to the prefrontal cortex, hippocampus and ventral (limbic) striatum, regions activated by visceral stimulation. Structural data support the idea that compartments of the non-discriminative thalamus may contribute to perception and behavioral responses to visceral stimulation.

Ophthalmic manifestations of trisomy 8 mosaic syndrome

Trisomy 8 mosaicism can present with a varied clinical picture. A significant number of cases have ocular manifestations. The most commonly reported in the literature have been corneal abnormalities and strabismus. We present a case of trisomy 8 mosaic syndrome with very different ophthalmic manifestations, some of which are previously unreported in the literature. The patient who was known to have trisomy 8 mosaic syndrome was referred with concerns about his visual abilities. He had a characteristic facial dysmorphism and other systemic features associated with this condition. Ophthalmic features included bilateral Duane's syndrome, bilateral myopic astigmatism, congenital pendular nystagmus, and macula hypoplasia. Electrodiagnostic tests confirmed extensive abnormality of cone function in both eyes. This case is discussed in relation to a review of the literature.

Early detection of nephrotoxic effects due to low-dose exposure of cadmium among cigarette smokers

The effects of low-level exposure to cadmium due to cigarette smoking on renal function were judged by the estimation of urinary levels of total proteins, cadmium, alpha-1-microglobulin (alpha1M) and glutathione S-transferase (GST) activity among 50 males (38 smokers and 12 control non-smokers). Elevated urinary cadmium levels [2.408-28.160; 9.31 +/- 7 .1 microg Cd/gm urine creatinine] were observed among the majority of smokers (24 cases, 63.16%) and these levels showed a positive correlation with age and smoking index. Furthermore, urine total proteins [115.18-652.14; 242.89 +/- 121.88 mg protein/gm urine creatinine) were increased suggesting glomerular involvement among 20 cases (52.63%) of smokers. In addition, urinary alpha1M levels (14.645-86.053; 34.05 +/- 16.83 mg alpha1M/gm urine creatinine) and urinary GST activity [0.0-0.008; 0.00015 +/- 0.0002 micromol/min/100 microl/gm urine creatinine] were elevated among 18 (47.37%) and 20 (52.63%) cases of smokers respectively. Since urinary alpha1M and GST originate from renal proximal tubules, the data of the present investigation could reflect early low-level cadmium exposure nephrotoxic effect on both the glomeruli and tubules.

Pseudotumour of the orbit: bilateral metachronous presentation

A case is presented of a pseudotumour that developed in the left orbit 4 years after surgery and histological confirmation of a pseudotumour in the right orbit. There was no evidence of any thyroid pathology.

Cerebral tuberculoma

Intracranial tuberculoma has become a rarity. It remains a curable lesion that responds well to medical therapy. Although diagnosis in developed countries is often made only postoperatively, early and effective treatment can be instituted if a high index of suspicion is maintained and diagnostic criteria are looked for. A case is presented which illustrates the difficulties in reaching a diagnosis, and a review of the literature is given.

Maternal tetanus immunization in Aceh Province, Sumatra: the cost-effectiveness of alternative strategies

This paper compares the cost per completed maternal tetanus immunization and an estimate of the cost per death averted in the routine EPI program with similar results from an experimental mass campaign in Aceh Province, Indonesia. The cost-effectiveness of the mass campaign in achieving complete immunization is similar to the routine program. However, the mass campaign is probably less cost-effective in averting neonatal tetanus deaths, due to its broader targetting. Factors affecting efficiency, coverage, and financing of tetanus immunization programs are assessed. While expansion of the routine EPI program is the preferred goal, mass campaigns are judged to be a reasonable part of the multi-year strategy for tetanus control in the province. Recent experiments with an accelerated routine program may provide further alternatives.

Cholera in Indonesia: epidemiologic studies of transmission in Aceh Province

To determine the modes of transmission of cholera in the regency of Pidie, Indonesia, and to consider strategies for its control, we set up a laboratory to identify Vibrio cholerae 01 from patients with severe diarrhea in all government clinics in the regency and questioned culture-positive cases and neighborhood controls about possible exposures to V. cholerae 01. Between 12 July and 15 August 1982, 63 of 138 suspected cholera cases were confirmed by the laboratory; 53 of these patients were seen and followed up. We were unable to identify a single, indisputable mode of transmission for cholera which was amenable to immediate control. Nonetheless, a number of factors, including exposure to water from the Tiro-Sigli River and consumption of ice, were associated with disease. Other findings bring into question the value of current practices of chlorinating dugwells and disinfecting homes with Lysol during a cholera outbreak. The case-control approach to investigating the mode of transmission of cholera has distinct limitations when applied in endemic setting where there may not be a single predominant vehicle of transmission, or where the vehicle such as river water is used by all and is only periodically contaminated.