Is it safe to discharge treated proliferative diabetic retinopathy patients from the hospital eye service to a community screening programme?

PURPOSE: To investigate the distribution of new vessels (NV) in patients treated with pan-retinal photocoagulation for proliferative diabetic retinopathy (PDR). To assess whether it is safe to discharge treated PDR patients to the NHS Diabetic Eye Screening Programme (DESP) which uses two mydriatic 45° fields of each eye. METHODS: Consecutive treated PDR patients undergoing fundus fluorescein angiography between July 2010 and October 2011 for the purpose of looking for NV were included. The distribution of NV was mapped. In particular it was noted whether NV occurred in the area covered by the DESP standard screening images. RESULTS: A total of 76 patients (108 eyes) met the inclusion criteria for the study. Leaking NV were found inside the DESP fields in 89% of study patients. In 108 eyes with leaking NV, there were a total of 35 NVD and 336 NVE. NV were found within DESP fields in 83% of eyes. Of the 336 NVE, 54% occurred within and 46% outside DESP standard fields. There was no statistically significant difference in the retinal quadrant distribution of NVE. CONCLUSIONS: If these findings apply to the whole treated PDR population, NVE would be identified in 89% of patients undergoing DESP screening. This would support stable treated PDR patients being monitored within the DESP. We found no preferential clustering of NV within quadrants or between posterior and less posterior retina suggesting that there would be no benefit to the DESP of taking an additional field or graders concentrating on one particular quadrant more than another.

A model for the management of an atypical endophthalmitis outbreak.

PURPOSE OF STUDY: To present a model for the assessment, investigation, and management of an atypical outbreak of infectious endophthalmitis of indeterminate aetiology. METHODS: A published statistical model was used to determine when the case-load constituted an outbreak. Intraocular surgery was discontinued and a multidisciplinary infection control team was formed aimed at identifying potential causative factors among the following categories: environment around theatre, preoperative preparation, intraoperative theatre practices, intraoperative surgical practices, postoperative practices, equipment maintenance guidelines, cleaning/sterilization practices, and microbiological screening. RESULTS: Five cases of postoperative endophthalmitis developed following uncomplicated phacoemulsification cataract surgery by different surgeons over a 7-month period. Despite full investigation no single focus of infection could be determined. Four out of five cases were culture positive. Three grew Streptococcus viridans of different strains. The fourth culture grew Staphylococcus aureus. In the absence of a single causative factor, it was postulated the combined effect of multiple potential factors may have led to an increased bacterial load and subsequent infection rate. Improved practices were initiated including new cleaning protocols to combat the build-up of debris on phacoemulsification instruments. Cataract surgery was resumed with 3-monthly microbiological monitoring. There have been no further cases in the 12 months following the changes. CONCLUSION: Outbreaks of endophthalmitis typically present over a short time period and could often be attributed to a single infective cause. We present our experience of detecting and managing this cluster and recommend a 'ground-up' multidisciplinary model to manage future outbreaks of this devastating condition.

The role of serum lipids in exudative diabetic maculopathy: is there a place for lipid lowering therapy?

Diabetic maculopathy is a common complication of diabetes mellitus, characterised by macular oedema and frequently accompanied by lipid exudation. It is the major cause of loss of vision from diabetic retinopathy. There is some evidence to implicate serum lipids in exudative maculopathy; cross-sectional studies suggest that higher serum lipid levels are found in patients with macular exudates, and prospective studies have shown an increased risk of exudative maculopathy if baseline cholesterol is higher. The treatment for diabetic maculopathy is laser photocoagulation of the pigment epithelium. With the advent of systemic lipid lowering therapy over the last decade, there may be potential for medical therapy also. There is some anecdotal evidence of the effect of lipid lowering agents (particularly statins) in reducing exudate, and a number of studies have shown that lipid lowering therapy may reduce macular exudates, but numbers in these trials are small. A randomised controlled trial is now required to investigate whether the use of systemic lipid lowering therapy is of benefit in patients with exudative maculopathy, even in the absence of dyslipidaemia.

Increased mortality in women with cataract: a population based follow up of the North London Eye Study.

BACKGROUND/AIMS: In diabetics, cataract is associated with higher risk of death. In non-diabetics the data are conflicting, but some indicate an association between one type of cataract (nuclear) and increased mortality. The aim of this study was to estimate and compare age and sex specific mortality for elderly people with and without cataract in a population based cohort. METHODS: A random sample drawn from a defined population of elderly people (age 65 and older) registered with 17 general practice groups in north London formed the study cohort and were followed up for 4 years. The age and sex specific mortality from various causes was estimated and compared in those with and without cataract. RESULTS: In non-diabetics (n=1318), cataract (lens opacity at baseline) was significantly associated with higher mortality in women. The age standardised death rate per 1000 was 39.8 and 24.8 in women with and without cataract, respectively (age adjusted hazard ratio 1.7, confidence limits 1.1 to 2.7, p=0.032). This was not the case in non-diabetic men (hazard ratio 0.9, confidence limits 0.6 to 1.5, p=0.782). The excess mortality in women with cataract was consistent for cardiovascular, respiratory, and other non-cancer causes of death. There was no association between cataract and mortality from cancer. CONCLUSIONS: This study has shown, for the first time, that cataract is associated with higher mortality in women but not in men, among the non-diabetic population. This sex effect suggests that women may be exposed to risk factors that increase both the risk of cataract and mortality, and that men may have little or no exposure to these "sex specific" factors. Possible risk factors that warrant further investigation may be those associated with some pregnancy and childbearing experience.

Pharmacotherapy of fungal eye infections.

Fungal eye infections are rare. Trauma associated with contamination by vegetative material, contact lens wear and long term corticosteroid use are common risk factors. The aims of treatment are to preserve visual function, which depends on the rapid diagnosis and efficient administration of appropriate antifungal therapy. This necessitates a clinical suspicion of fungal aetiology and the taking of appropriate smears and cultures as early as possible to identify the fungal organism. Currently there are three main classes of drugs available for use in fungal eye infections: polyenes, azoles as derivatives of imidazoles, and 5-fluorocytosine. Of the polyenes, amphotericin B, natamycin and nystatin are of clinical ophthalmic use. Based on better pharmacokinetic profiles and spectra of antifungal activity, the triazoles are the agents of choice. Successful treatment of fungal keratitis depends on early initiation of specific therapy consisting of topically-applied antifungal agents since topical administration is most likely to provide the best opportunity for achieving therapeutic corneal levels. Hence, the molecular weight of the various antifungal agents is of importance since it influences their ability to penetrate the corneal epithelium. Systemic administration may be necessary for resistant fungal ulcers. For fungal endophthalmitis, to preserve visual function and eliminate the fungal pathogen, topical, systemic and possibly intraocular antifungal therapy is used, although some do not recommend use of systemic agents for exogenous endophthalmitis.

The deficit in cataract surgery in England and Wales and the escalating problem of visual impairment: epidemiological modelling of the population dynamics of cataract.

BACKGROUND: The pool of old cases of cataract, the expected new cases, and the shortfall in cataract surgery and consequently the numbers dying with poor vision without the benefit of cataract surgery are regarded as escalating problems worldwide. Successive governments and the professional ophthalmic bodies have not had the wherewithal to estimate the magnitude or interaction of these elements in the population of the UK. This study has collected and applied the best available epidemiological data on cataract prevalence, incidence and service utilisation, and demography to address the problem of control of the cataract pool in the population of England and Wales. METHODS: Data from recent surveys undertaken by the authors, both on prevalence of vision impairing cataract and on patterns of cataract surgery, were used together with demographic and service utilisation information obtained from government departments. These were integrated within a holistic model, which was run under varied assumed levels and patterns of service provision. RESULTS: The study shows that there is a serious pool of unoperated vision impairing cataract in the population aged 65 and older, reflecting a shortfall in cataract surgery. Continuing with the present level and pattern of service provision, the pool will increase to over 2.5 million by the year 2001. In addition, more than 700 000 will die with unoperated impaired vision. CONCLUSIONS: Targeting of existing or new additional operations to those below the visual acuity of 6/12 will have relatively little effect on numbers dying without surgery, but should have a substantial controlling effect on the pool of vision impairing cataract in the population.

Attitudes after unintended injury during treatment a survey of doctors and patients.

OBJECTIVE: To compare the attitudes of doctors and patients toward the disclosure of information after adverse medical events. DESIGN: Cross-sectional questionnaire survey. SETTING: Ophthalmology department of an outer London hospital. SUBJECTS: 246 patients attending one ophthalmic outpatient clinic during a 5-week period and 48 ophthalmologists. MAIN OUTCOME MEASURE: Proportion of each group who believed that patients should be informed about the occurrence of an adverse event and its potential future complications following elective ophthalmic surgery. RESULTS: Most patients (226/246, 91.8%) believed that a patient should be informed of an adverse event. Fewer ophthalmologists (29/48, 60.5%, P<0.001; odds ratio 7.4 [95% CI 3.7-14.3]) shared this belief. The majority of patients (200/246, 88.5%) believed that a patient should be as fully informed as possible about the event and possible future complications, but this belief was shared by a minority of ophthalmologists (16/48, 33.3%, P<0.001; odds ratio 8.7 [95% CI 4.7-15.9]). CONCLUSION: After an adverse medical event, there is a discrepancy between the amount of information that patients wish to be given and that which physicians feel is appropriate.

Prevalence of serious eye disease and visual impairment in a north London population: population based, cross sectional study.

OBJECTIVE: To estimate the magnitude of serious eye disorders and of visual impairment in a defined elderly population of a typical metropolitan area in England, and to assess the frequency they were in touch with, or known to, the eye care services. DESIGN: Cross sectional survey using two stage cluster random sampling. SETTING: General practices in north London. SUBJECTS: Random sample of people aged 65 and older, drawn from a defined population of elderly people registered with 17 general practice groups. MAIN OUTCOME MEASURES: Proportions and population prevalence estimates were determined for visual acuity, assessed with the person's own spectacles (if any), classified into four categories: prevalence of cataract, age related macular degeneration, and refractive error causing visual impairment and of definite primary open angle glaucoma; and status of contact with eye services. RESULTS: 1547 of 1840 (84%) eligible people were examined. The population prevalence of bilateral visual impairment (visual acuity <6/12) was 30%, of which 72% was potentially remediable. 92 of these 448 cases (21%) had visual acuity <6/60 ("blindness") in one or both eyes. Prevalence of cataract causing visual impairment was 30%; 88% of these people were not in touch with the eye services. The prevalence of vision impairing, age related macular degeneration was 8% and of glaucoma (definite cases) was 3%. Three quarters of the people with definite glaucoma were not known to the eye services. CONCLUSIONS: Untreated visual impairment and eye disorders affect a substantial proportion of people aged 65 years and older. These findings should contribute to the setting up of future strategies for preservation of sight and eye health services in general.

Safe Child Penarth: experience with a Safe Community strategy for preventing injuries to children.

OBJECTIVES: To evaluate the process of establishing a Safe Community project for children. DESIGN: A descriptive study. SETTING: Penarth, a town (population 20,430) Vale of Glamorgan, South Wales. SUBJECTS: 3943 children and their families in Penarth. MAIN OUTCOME MEASURES: Whether the 12 criteria for a Safe Community project (World Health Organisation) were met. Implementation of the safety agenda set by the community. RESULTS: Safe Child Penarth met 10 of the 12 criteria for the Safe Community network. All the items on the agenda were introduced in the initial two years of the project. There were difficulties, however, achieving sustained community ownership of the project. CONCLUSIONS: The Safe Community concept stimulated work to improve child safety in Penarth. Community safety initiatives should involve all local agencies to identify the problems and work with the community to set and meet the safety agenda. Partnership with the local authority is valuable to improve the safety of the environment. The experience generated from Safe Child Penarth has been used to develop a county wide, all age community safety project.

Gains from cataract surgery: visual function and quality of life.

AIMS: To describe the impact of cataract surgery in terms of visual function (functioning in everyday life with respect to vision dependent activities) and health related quality of life. METHODS: An observational, longitudinal study of patients undergoing cataract surgery was carried out at three district general hospitals in outer London districts of North Thames Region with follow up at 4 and 12 months postoperatively for a clinical assessment and a standardised administered interview. Patients were admitted for surgery to the first eye for age-related cataract between 1 May 1993 and 31 August 1994. Visual functioning was assessed by the VF-14, health related quality of life was assessed by the sickness impact profile (SIP), and vision related quality of life was assessed by VR-SIP (a modification of the generic SIP). RESULTS: Significant gains in all the outcome measures were demonstrated at 4 months postoperatively. No significant change (gain or loss) was observed between 4 and 12 months after surgery to the first eye. Postoperatively, the mean visual function (VF-14) scores, and health related (SIP) and vision related (VR-SIP) quality of life scores, indicated less reported trouble with vision dependent activities and better perceived quality of life, respectively. The average gains in visual function and quality of life (health and vision related) were apparent in groups with good visual outcome and poor visual outcome. Significant additional gains were seen at 1 year in patients who had second eye surgery in the interval between the postoperative assessments. CONCLUSIONS: Gains in visual functioning and quality of life (health and vision related) have been demonstrated following cataract surgery. These gains were sustained at 1 year after surgery to the first eye, with additional gains being conferred if second eye surgery had been performed. Assessment of the outcomes of cataract surgery by clinical indicators alone may underestimate the overall benefits of surgery, particularly in patients with poor visual outcome.

Postoperative morbidity following cataract surgery. A comparison of local and general anaesthesia.

Two hundred and thirty-one patients were questioned the day following their cataract surgery to ascertain the incidence of postoperative morbidity. One hundred and nineteen patients received local anaesthesia (LA) and 112 received general anaesthesia (GA). There was a significant difference in the incidence of nausea (21% in GA group, 3% in LA group, p < 0.01), sore throat (41% GA group, 3% LA group, p < 0.01), and bruising of the eye (15% GA group, 39% LA group, p < 0.01). There was no significant difference in the incidence of vomiting, headache, double vision, the severity of postoperative pain, or the need for analgesia. The time before the patients drank and ate postoperatively was significantly shorter in the local anaesthetic group (1.3 h and 1.8 h LA group, 4.1 h and 6.7 h GA group respectively, p < 0.01).

Investigation of benefits and costs of an ophthalmic outreach clinic in general practice.

BACKGROUND: With the advent of general practitioner fundholding, there has been growth in outreach clinics covering many specialties. The benefits and costs of this model of service provision are unclear. AIM: A pilot study aimed to evaluate an outreach model of ophthalmic care in terms of its impact on general practitioners, their use of secondary ophthalmology services, patients' views, and costs. METHOD: A prospective study, from April 1992 to March 1993, of the introduction of an ophthalmic outreach service in 17 general practices in London was undertaken. An ophthalmic outreach team, comprising an ophthalmic medical practitioner and an ophthalmic nurse, held clinics in the practices once a month. Referral rates to Edgware General Hospital ophthalmology outpatient department over one year from the study practices were compared with those from 17 control practices. General practitioners' assessments of the scheme and its impact on their knowledge and practice of ophthalmology were sought through a postal survey of all partners and interviews with one partner in each practice. Patient surveys were conducted using self-administered structured questionnaires. A costings exercise compared the outreach model with the conventional hospital ophthalmology outpatient clinic. RESULTS: Of 1309 patients seen by the outreach team in the study practices, 480 (37%) were referred to the ophthalmology outpatient department. The annual referral rate to this department from control practices was 9.5 per 10,000 registered patients compared with 3.8 per 10,000 registered patients from study practices. A total of 1187 patients were referred to the outpatient department from control practices. An increase in knowledge of ophthalmology was reported by 18 of 47 general practitioners (38%). Nineteen (40%) of 47 general practitioners took advantage of the opportunity for inservice training with the outreach team; they were more likely to change their routine practice for ophthalmic care or referral criteria for patients with cataracts or diabetes than those who did not attend for inservice training. The outreach scheme was popular with patients, for whom ease of access and familiarity of surroundings were major advantages. The cost per patient seen in the outreach clinics (48.09 pounds) was about three times the cost per patient seen in the outpatient department (15.71 pounds). CONCLUSION: The model of ophthalmic outreach care in this pilot study was popular with patients and general practitioners and appeared to act as an effective filter of demand for care in the hospital setting. However, the educational impact of the scheme was limited. Although the unit costs (per patient) of the outreach scheme compared unfavourably with those of conventional outpatient treatment, potential health gains from this more accessible model of care require further exploration.

Metabolic control of non-insulin-dependent diabetic patients undergoing cataract surgery: comparison of local and general anaesthesia.

We studied 40 elderly patients undergoing cataract surgery. Ten non-insulin-dependent diabetes mellitus (NIDDM) patients received standardized general anaesthesia, 10 NIDDM patients received local anaesthesia using retrobulbar block, 10 non-diabetic control patients received general anaesthesia and 10 non-diabetic controls received retrobulbar block. We measured sequential changes in blood glucose, lactate and beta-hydroxybutyrate, serum cortisol and insulin, and plasma non-esterified fatty acid concentrations until 4 h after operation. The results showed that in both general anaesthesia groups, NIDDM and control, blood glucose and serum cortisol concentrations increased significantly during surgery, before returning to normal by 4 h after operation; in both local anaesthesia groups, glucose and cortisol concentrations changed little during surgery. Serum insulin concentrations increased 30 min after operation to coincide with the peak of the glucose increase in the non-diabetic patients who received general anaesthesia, but no insulin response was seen in the diabetic general anaesthesia patients. Blood glucose and insulin concentrations increased in patients who received local anaesthesia (NIDDM and controls) when they ate after operation. The results show that cataract surgery under local anaesthesia provides improved metabolic control for the diabetic patient. Its use maintains glucose homeostasis, prevents the increases in cortisol and glucose which are seen under general anaesthesia and obviates the need for postoperative starvation.

Retrobulbar block fails to prevent an increase in serum cortisol concentration on emergence from anaesthesia after cataract surgery.

We have studied 30 elderly patients undergoing cataract surgery, allocated randomly to receive general anesthesia, local anaesthesia by retrobulbar block or general anaesthesia combined with retrobulbar block given after induction. Retrobulbar block alone prevented the increases in circulating cortisol and glucose values which occurred in those patients receiving general anaesthesia alone. Retrobulbar block given after induction of general anaesthesia, however, suppressed the cortisol and glucose response during surgery, but did not prevent a marked increase in cortisol concentrations during the immediate postoperative period. The results suggest a hormonal response to emergence from anaesthesia which has hitherto been masked by the stress response to surgery itself.

The metabolic and hormonal response to cataract surgery. A comparison between retrobulbar and peribulbar blockade.

We studied the metabolic and hormonal responses of 30 elderly patients undergoing routine cataract surgery who were allocated randomly to receive either general anaesthesia, or local anaesthesia by means of either retrobulbar or peribulbar blockade. Both forms of local anaesthesia successfully prevented the increases in circulating cortisol and glucose concentrations seen in those patients who received general anaesthesia, there being no significant differences between retrobulbar and peribulbar blockade. The results show that the newer, and now more commonly performed peribulbar block, confers the same metabolic and hormonal stability as seen with the more traditional retrobulbar block.

Plasma catecholamine response to cataract surgery: a comparison between general and local anaesthesia.

We studied the plasma catecholamine, plasma glucose and cardiovascular responses to cataract surgery in 20 elderly patients allocated randomly to receive either general anaesthesia or local anaesthesia by retrobulbar block. Local anaesthesia prevented the increase in plasma noradrenaline, adrenaline and glucose concentrations found in those patients who received general anaesthesia and also improved cardiovascular stability. The results show the beneficial effects of local anaesthesia in preventing the hormonal, metabolic and cardiovascular changes found when cataract surgery is conducted under general anaesthesia.