Childhood visual impairment in England: a rising trend

AIM

To explore temporal trends in the incidence of childhood blindness and partial-sight registration in England between 1982 and 2011.

METHODS

We obtained blind and partial-sight registration data for all new individuals registered annually in England. We calculated the age-specific incidence of new registrations for childhood blind and partial sight.

RESULTS

The incidence of new registration for blindness of all ages has decreased from 2.6 per 10 000 in 1982 to 1.7 per 10 000 in 2011, however the annual incidence of new paediatric blind registration has increased, with an incidence of 0.17 per 10 000 in 1982, doubling to 0.41 per 10 000 in 2011. The annual incidence of new paediatric partial-sight registration showed a comparable trend.

CONCLUSIONS

Over 30 years, there has been a greater than twofold increase in blind and partial-sight registration in children in England. Better awareness of this is needed to ensure adequate resources are available to help these children.

The effectiveness of schemes that refine referrals between primary and secondary care--the UK experience with glaucoma referrals: the Health Innovation & Education Cluster (HIEC) Glaucoma Pathways Project

OBJECTIVES

A comparison of glaucoma referral refinement schemes (GRRS) in the UK during a time period of considerable change in national policy and guidance.

DESIGN

Retrospective multisite review.

SETTING

The outcomes of clinical examinations by optometrists with a specialist interest in glaucoma (OSIs) were compared with optometrists with no specialist interest in glaucoma (non-OSIs). Data from Huntingdon and Nottingham assessed non-OSI findings, while Manchester and Gloucestershire reviewed OSI findings.

PARTICIPANTS

1086 patients. 434 patients were from Huntingdon, 179 from Manchester, 204 from Gloucestershire and 269 from Nottingham.

RESULTS

The first-visit discharge rate (FVDR) for all time periods for OSIs was 14.1% compared with 36.1% from non-OSIs (difference 22%, CI 16.9% to 26.7%; p<0.001). The FVDR increased after the April 2009 National Institute for Health and Clinical Excellence (NICE) glaucoma guidelines compared with pre-NICE, which was particularly evident when pre-NICE was compared with the current practice time period (OSIs 6.2-17.2%, difference 11%, CI -24.7% to 4.3%; p=0.18, non-OSIs 29.2-43.9%, difference 14.7%, CI -27.8% to -0.30%; p=0.03). Elevated intraocular pressure (IOP) was the commonest reason for referral for OSIs and non-OSIs, 28.7% and 36.1%, respectively, of total referrals. The proportion of referrals for elevated IOP increased from 10.9% pre-NICE to 28.0% post-NICE for OSIs, and from 19% to 45.1% for non-OSIs.

CONCLUSIONS

In terms of 'demand management', OSIs can reduce FVDR of patients reviewed in secondary care; however, in terms of 'patient safety' this study also shows that overemphasis on IOP as a criterion for referral is having an adverse effect on both the non-OSIs and indeed the OSIs ability to detect glaucomatous optic nerve features. It is recommended that referral letters from non-OSIs be stratified for risk, directing high-risk patients straight to secondary care, and low-risk patients to OSIs.

How to achieve universal coverage of cataract surgical services in developing countries: lessons from systematic reviews of other services

PURPOSE

Since the Declaration of Alma Ata, universal coverage has been at the heart of international health. The purpose of this study was to review the evidence on factors and interventions which are effective in promoting coverage and access to cataract and other health services, focusing on developing countries.

METHODS

A thorough literature search for systematic reviews was conducted. Information resources searched were Medline, The Cochrane Library and the Health System Evidence database. Medline was searched from January 1950 to June 2010. The Cochrane Library search consisted of identifying all systematic reviews produced by the Cochrane Eyes and Vision Group and the Cochrane Effective Practice and Organisation of Care. These reviews were assessed for potential inclusion in the review. The Health Systems Evidence database hosted by MacMaster University was searched to identify overviews of systematic reviews.

RESULTS

No reviews met the inclusion criteria for cataract surgery. The literature search on other health sectors identified 23 systematic reviews providing robust evidence on the main factors facilitating universal coverage. The main enabling factors influencing access to services in developing countries were peer education, the deployment of staff to rural areas, task shifting, integration of services, supervision of health staff, eliminating user fees and scaling up of health insurance schemes.

CONCLUSION

There are significant research gaps in eye care. There is a pressing need for further high quality primary research on health systems-related factors to understand how the delivery of eye care services and health systems' capacities are interrelated.

Ivermectin for onchocercal eye disease (river blindness)

BACKGROUND

It is believed that ivermectin (a microfilaricide) could prevent blindness due to onchocerciasis. However, when given to everyone in communities where onchocerciasis is common, the effects of ivermectin on lesions affecting the eye are uncertain and data on whether the drug prevents visual loss are unclear.

OBJECTIVES

The aim of this review was to assess the effectiveness of ivermectin in preventing visual impairment and visual field loss in onchocercal eye disease. The secondary aim was to assess the effects of ivermectin on lesions affecting the eye in onchocerciasis.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 3), MEDLINE (January 1950 to April 2012), EMBASE (January 1980 to April 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 2 April 2012.

SELECTION CRITERIA

We included randomised controlled trials with at least one year of follow-up comparing ivermectin with placebo or no treatment. Participants in the trials were people normally resident in endemic onchocercal communities with or without one or more characteristic signs of ocular onchocerciasis.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality. We contacted study authors for additional information. As trials varied in design and setting, we were unable to perform a meta-analysis.

MAIN RESULTS

The review included four trials: two small studies (n = 398) in which people with onchocercal infection were given one dose of ivermectin or placebo and followed up for one year; and two larger community-based studies (n = 4941) whereby all individuals in selected communities were treated every six or 12 months with ivermectin or placebo, whether or not they were infected, and followed for two to three years. The studies provide evidence that treating people who have onchocerciasis with ivermectin reduces the number of microfilariae in their skin and eye(s) and reduces the number of punctate opacities. There was weaker evidence that ivermectin reduced the risk of chorioretinitis. The studies were too small and of too short a duration to provide evidence for an effect on sclerosing keratitis, iridocyclitis, optic nerve disease or visual loss. One community-based study in communities mesoendemic for the savannah strain of O.volvulus provided evidence that annual mass treatment with ivermectin reduces the risk of new cases of optic nerve disease and visual field loss. The other community-based study of mass biannual treatment of ivermectin in communities affected by the forest strain of O.volvulus demonstrated reductions in microfilarial load, punctate keratitis and iridocyclitis but not sclerosing keratitis, chorioretinitis, optic atrophy or visual impairment. The study was underpowered to estimate the effect of ivermectin on visual impairment and other less frequent clinical signs. The studies included in this review reported some adverse effects, in particular an increased risk of postural hypotension in people treated with ivermectin.

AUTHORS' CONCLUSIONS

The lack of evidence for prevention of visual impairment and blindness should not be interpreted to mean that ivermectin is not effective, however, clearly this is a key question that remains unanswered. The main evidence for a protective effect of mass treatment with ivermectin on visual field loss and optic nerve disease comes from communities mesoendemic for the savannah strain of O.volvulus. Whether these findings can be applied to communities with different endemicity and affected by the forest strain is unclear. Serious adverse effects were rarely reported. None of the studies, however, were conducted in areas where people are infected with Loa loa (loiasis).

The estimated prevalence and incidence of late stage age related macular degeneration in the UK

BACKGROUND

UK estimates of age related macular degeneration (AMD) occurrence vary.

AIMS

To estimate prevalence, number and incidence of AMD by type in the UK population aged ≥50 years.

METHODS

Age-specific prevalence rates of AMD obtained from a Bayesian meta-analysis of AMD prevalence were applied to UK 2007-2009 population data. Incidence was estimated from modelled age-specific prevalence.

RESULTS

Overall prevalence of late AMD was 2.4% (95% credible interval (CrI) 1.7% to 3.3%), equivalent to 513 000 cases (95% CrI 363 000 to 699 000); estimated to increase to 679 000 cases by 2020. Prevalences were 4.8% aged ≥65 years, 12.2% aged ≥80 years. Geographical atrophy (GA) prevalence rates were 1.3% (95% CrI 0.9% to 1.9%), 2.6% (95% CrI 1.8% to 3.7%) and 6.7% (95% CrI 4.6% to 9.6%); neovascular AMD (NVAMD) 1.2% (95% CrI 0.9% to 1.7%), 2.5% (95% CrI 1.8% to 3.4%) and 6.3% (95% CrI 4.5% to 8.6%), respectively. The estimated number of prevalent cases of late AMD were 60% higher in women versus men (314 000 cases in women, 192 000 men). Annual incidence of late AMD, GA and NVAMD per 1000 women was 4.1 (95% CrI 2.4% to 6.8%), 2.4 (95% CrI 1.5% to 3.9%) and 2.3 (95% CrI 1.4% to 4.0%); in men 2.6 (95% CrI 1.5% to 4.4%), 1.7 (95% CrI 1.0% to 2.8%) and 1.4 (95% CrI 0.8% to 2.4%), respectively. 71 000 new cases of late AMD were estimated per year.

CONCLUSIONS

These estimates will guide health and social service provision for those with late AMD and enable estimation of the cost of introducing new treatments.

Geographical variation in certification rates of blindness and sight impairment in England, 2008-2009

OBJECTIVES

To examine and interpret the variation in the incidence of blindness and sight impairment in England by PCT, as reported by the Certificate of Vision Impairment (CVI).

DESIGN

Analysis of national certification data.

SETTING

All Primary Care Trusts, England.

PARTICIPANTS

23 773 CVI certifications issued from 2008 to 2009.

MAIN OUTCOME MEASURES

Crude and Age standardised rates of CVI data for blindness and sight loss by PCT.

METHODS

The crude and age standardised CVI rates per 100 000 were calculated with Spearman's rank correlation used to assess whether there was any evidence of association between CVI rates with Index of Multiple Deprivation (IMD) and the Programme Spend for Vision.

RESULTS

There was high-level variation, almost 11-fold (coefficient of variation 38%) in standardised CVI blindness and sight impairment annual certification rates across PCTs. The mean rate was 43.7 and the SD 16.7. We found little evidence of an association between the rate of blindness and sight impairment with either the IMD or Programme Spend on Vision.

CONCLUSIONS

The wide geographical variation we found raises questions about the quality of the data and whether there is genuine unmet need for prevention of sight loss. It is a concern for public health practitioners who will be interpreting these data locally and nationally as the CVI data will form the basis of the public health indicator 'preventable sight loss'. Poor-quality data and inadequate interpretation will only create confusion if not addressed adequately from the outset. There is an urgent need to address the shortcomings of the current data collection system and to educate all public health practitioners.

Ectopic olfactory neuroblastoma: report of four cases and a review of the literature

Our objective is to present a short series of four rare cases of ectopic olfactory neuroblastoma. Our methods present four case reports of ectopic olfactory neuroblastoma and a review of the literature for management and treatment of this disease. The results indicate short case series reports of ectopic olfactory neuroblastoma arising from the anterior ethmoidal sinuses, the nasopharynx, the lateral nasal wall and the floor of the nose. The discussion focuses on likely origins of ectopic olfactory neuroblastoma, its clinical features and management. We conclude that ectopic olfactory neuroblastoma is a rare disease. Treatment principles are the same for non-ectopic disease and guided by extension into adjacent structures such as the orbit or anterior cranial fossa and usually involves surgery with or without adjuvant radiotherapy.

Cochrane Eyes and Vision Group (CEVG)

This is a new column for reviews from the Cochrane Eyes and Vision Group (CEVG). Its main aim is to promote access to systematic reviews of all the interventions used to prevent or treat eye diseases. It is based at the London School of Hygiene & Tropical Medicine in London, UK, and Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland, USA.

Causes of blind and partial sight certifications in England and Wales: April 2007-March 2008

PURPOSE

The last complete report on causes of blindness in England and Wales was for the data collected during April 1999-March 2000. This study updates these figures, with data collected during April 2007-March 2008.

METHODS

In England and Wales, registration for blindness and partial sight is initiated with certification by a consultant ophthalmologist with the consent of the patient. The main cause of visual impairment was ascertained where possible for all certificates completed during April 2007-March 2008 and a proportional comparison with 1999-2000 figures was made.

RESULTS

We received 23,185 Certificates of Vision Impairment (CVIs), of which 9823 were for severe sight impairment (blindness) (SSI) and 12,607 were for sight impairment (partial sight) (SI). These totals were considerably lower than the numbers certified in the year ending 31 March 2000. In 16.6% of CVIs, there were multiple causes of visual impairment as compared with 3% of BD8s in 2000. Degeneration of the macula and posterior pole (mostly age-related macular degeneration (AMD)) contributed to vision impairment in 12,746 newly certified blind or partially sighted.

CONCLUSIONS

AMD is still by far the leading cause of certified visual loss in England and Wales. Proportional comparisons are hampered by the increasing use of multiple pathology as a main cause of visual impairment, which is believed to have arisen owing to the change in certificate used for data collection. These figures are not estimates of the total numbers newly blind in the UK because not all those entitled to certification are offered and or accept it, but they do nevertheless document the number of people who are deemed to be sufficiently sight impaired to warrant support and have been both offered and accepted it. This is usually the case when no further ophthalmic intervention is thought likely to be of benefit in terms of restoring or improving vision.

The Peterborough scheme for community specialist optometrists in glaucoma: a feasibility study

PURPOSE

This study assessed the role of specialist optometrists who were working in the community and sharing the care for glaucoma patients with, and under close supervision of, a consultant ophthalmologist working in the Hospital Eye Services (HES) to ensure high-quality standards, safety, and care.

METHODS

From February 2005 onwards, the majority of all new glaucoma referrals to our eye department were diverted to our specialist optometrists in glaucoma (SOGs) in their own community practices. Selected patients in the HES setting who were already diagnosed with stable glaucoma were also transferred to the SOGs. The completed clinical finding details of the SOGs, including fundus photographs and Humphrey visual field tests, were scrutinised by the project lead.

RESULTS

This study included 1184 new patients seen by specialist optometrists between February 2005 and March 2007. A total of 32% of patients were referred on to the hospital, leaving the remaining 68% patients to be seen for at least their next consultation in the community by the SOGs. The following levels of disagreement were observed between SOGs and the project lead: on cup:disc ratio (11%), visual field interpretation (7%), diagnosis (12%), treatment plan (10%), and outcome (follow-up interval and location) (17%).

CONCLUSION

This study indicates that there is potential for a significant increase in the role of primary care optometry in glaucoma management. The study also confirms a need for a significant element of supervision and advice from a glaucoma specialist. The important issue of cost effectiveness is yet to be confirmed.

Hypotensive medication, statins, and the risk of glaucoma

PURPOSE. To examine whether treatment with oral blood-pressure-lowering medication or statins influences the risk of glaucoma. METHODS. This study was a case-control investigation, nested within a computerized primary care database of 177 general practices across the United Kingdom; 8778 cases diagnosed and/or treated for glaucoma between 2000 and 2007, and 8778 glaucoma-free controls matched for age, sex, and practice. Odds ratios for treatment with oral antihypertensives (including selective beta(1) and nonselective beta-blockers) and statins in the 5 years before diagnosis were calculated by logistic regression, adjusted for a marker of socioeconomic position and number of drug types prescribed (as a measure of health service usage). RESULTS. Prevalence of oral beta-blocker use in the 5 years before diagnosis was lower in the cases (22.5%) than in the controls (23.6%), adjusted odds ratio (OR) 0.87 (95% confidence interval [CI], 0.80-0.94). This effect was presence with treatment with beta(1)-selective medications (OR, 0.81; 95% CI, 0.74-0.88) but not with nonselective medications (OR, 1.08; 95% CI, 0.94-1.24). The prevalence of thiazide use was higher among the glaucoma cases than among the controls (OR, 1.13; 95% CI, 1.04-1.23). Neither statins nor other antihypertensive treatments were associated with the risk of glaucoma. CONCLUSIONS. Oral beta(1) beta-blockers may protect against development of glaucoma. The current consensus on the relative importance of beta(2) receptor blockade in treating glaucoma may have to be reviewed. Changes in prescribing oral beta-blockers for cardiovascular disorders may affect the number of those who eventually have glaucoma. There is no evidence to suggest that statins have a preventive role in glaucoma.