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Objective: To define theoretical correction factors for second-eye intraocular lens (IOL) power adjustment based on first eye refractive prediction error (PE)., Design: Database study., Participants: We included 2129 patients who underwent bilateral sequential phacoemulsification cataract surgery with the same IOL model., Methods: Retrospectively calculated PEs (Hoffer Q, Holladay 1, SRK/T) were analyzed for association between paired eyes, examining the effect of interocular differences in axial length (AL) and corneal power. A range of correction factors (CF) derived from the first eye PE were applied to the second eye PE using optimized and non-optimized IOL constants (IOLCs)., Main Outcome Measures: Second eye mean absolute error (MAE)., Results: Prediction errors of paired eyes were correlated. Interocular corneal power differences exceeding 0.60 diopters (D) were associated with a weaker correlation but interocular AL differences did not affect the correlation. When a 50% CF was applied to second eyes of patients with a first eye PE between ±0.50 and ±1.50 D, it improved refractive outcomes from 30%, 56%, and 92% to 42%, 75%, and 96% within ±0.25 D, ±0.50 D and ±1.00 D, respectively, and reduced the MAE from 0.49 to 0.37 D (P<0.0001). For first eye PE below ±0.50 D, a 50% CF reduced the MAE from 0.32 to 0.30 D (P<0.00001). A 50% CF also reduces second eye MAE for eyes with nonoptimized IOLCs., Conclusions: A 50% CF reduces second eye PE when either first eye optimized PE is within ±1.50 D or when nonoptimized IOLCs are used. The correlation is weaker when interocular corneal power differences are >0.60 D., (Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Aims: To develop a methodology for case-mix adjustment of surgical outcomes for individual cataract surgeons using electronically collected multi-centre data conforming to the cataract national data set (CND)., Methods: Routinely collected anonymised data were remotely extracted from electronic patient record (EPR) systems in 12 participating NHS Trusts undertaking cataract surgery. Following data checks and cleaning, analyses were carried out to risk adjust outcomes for posterior capsule rupture rates for individual surgeons, with stratification by surgical grade., Results: A total of 406 surgeons from 12 NHS Trusts submitted data on 55,567 cataract operations between November 2001 and July 2006 (86% from January 2004). In all, 283 surgeons contributed data on >25 cases, providing 54,319 operations suitable for detailed analysis. Case-mix adjusted results of individual surgeons are presented as funnel plots for all surgeons together, and separately for three different grades of surgeon. Plots include 95 and 99.8% confidence limits around the case-mix adjusted outcomes for detection of surgical outliers., Conclusions: Routinely collected electronic data conforming to the CND provides sufficient detail for case-mix adjustment of cataract surgical outcomes. The validation of these risk indicators should be carried out using fresh data to confirm the validity of the risk model. Once validated this model should provide an equitable approach for peer-to-peer comparisons in the context of revalidation.

Purpose: To compare the diurnal intraocular pressure (IOP) profile pre and post trabeculectomy with a control group of medically controlled patients. We compared the change in mean, peak, and diurnal IOP fluctuation., Methods: This was an observational study of patients at the Bristol Eye Hospital, United Kingdom. All patients underwent initial and subsequent phasing, with surgery between for cases. The unpaired Student t test compared the changes (initial-subsequent) in mean, peak, and fluctuation between cases and controls., Results: Fifteen eyes underwent trabeculectomy surgery while the control group contained 17 eyes controlled on topical medical treatment. There was a statistically significant reduction in both mean IOP of 3.7 mmHg (p=0.002) and peak IOP of 4.4 mmHg (p=0.025) in the surgical group compared to the medical group. There was no statistically significant change in the IOP fluctuation between the 2 study groups (p=0.296)., Conclusions: There is a significant reduction in mean IOP and peak IOP following trabeculectomy. We showed no statistically significant change in the diurnal fluctuation of IOP following trabeculectomy.

Aims/purpose: To determine the prevalence of age-related maculopathy (ARM) and age-related macular degeneration (AMD) in men aged 65-83 years living in the Speedwell region of Bristol, United Kingdom and identify modifiable risk factors., Methods: A total of 2348 men recruited to the Speedwell prospective cohort study in 1979 were followed up in 1997 with an eye questionnaire and had retinal photographs that were assessed using the International Classification System for ARM., Results: In all, 934 men (66.8% response rate) attended with a mean of 17.9 years (15.3-20.6 years) follow-up. Early ARM (grades 2-3) was found in 9.2% (95% confidence interval (CI) 7.4%, 11.4%) and late age-related maculopathy (grade 4, AMD) in 0.5% (95% CI 0.2%, 1.2%). The risk of ARM (grades 2-4) was increased with raised C-reactive protein and consumption of lard and solid fats, whereas triglyceride levels were associated with a lower risk. The latter were confirmed in multivariable analyses and in addition, haemodynamic measures also predicted risk (eg mean arterial pressure odds ratio (OR) per z-score 1.37, 95% CI 1.04, 1.79)., Conclusions: In a representative cohort of men aged 65-83 from Bristol, United Kingdom, many had macular changes that put them at higher risk of developing AMD. Various modifiable exposures were associated with an increased risk ARM/AMD. Opportunities for screening and undertaking secondary prevention interventions need to be explored to prevent progression of the disease and blindness.

Purpose: To assess the benefits of intraocular lens (IOL)-constant optimization for IOLMaster biometry on refractive outcomes after cataract surgery for all surgeons and individual surgeons, define acceptable levels of error in IOL-constant optimization, and calculate the minimum number of eyes required for IOL-constant optimization., Setting: Department of Ophthalmology, Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, United Kingdom., Design: Database study., Methods: Hypothetical prediction errors were retrospectively calculated on prospectively collected data extracted from electronic medical records using manufacturers' and optimized IOL constants with Hoffer Q, Holladay 1, and SRK/T formulas for 2 IOLs. The acceptable IOL-constant optimization error margins, personalized IOL constants for individual surgeons, and minimum sample sizes for IOL-constant optimization were evaluated., Results: Optimization of IOL constants reduced the mean absolute errors from 0.66 diopters (D) and 0.52 D to 0.40 D and 0.42 D for the Sofport AO IOL and Akreos Fit IOL, respectively. The percentage of eyes within ±0.25 D, ±0.50 D, and ±1.00 D of target refraction improved from for both IOL models. The IOL-constant errors exceeding 0.09 for the Hoffer Q, 0.09 for the Holladay 1, and 0.15 for the SRK/T produced inferior outcomes. Differences in personalized IOL constants between most surgeons were clinically insignificant. Calculating IOL constants to within 0.06, 0.06, and 0.10 for the Hoffer Q, Holladay 1, and SRK/T, respectively, required 148 to 257 eyes., Conclusions: Optimizing IOL constants for IOLMaster biometry substantially improved refractive outcomes, far exceeding any additional benefit of personalizing IOL constants for individual surgeons., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosure is found in the footnotes., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess how intraocular lens (IOL) formula choice affects refractive outcomes after cataract surgery using IOLMaster biometry., Setting: Department of Ophthalmology, Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, United Kingdom., Design: Database study., Methods: Hypothetical prediction errors were retrospectively calculated on prospectively collected data from electronic medical records using optimized Hoffer Q, Holladay 1, and SRK/T formulas (Sofport AO and Akreos Fit IOLs) across a range of 0.5 mm or 1.0 mm axial length (AL) subgroups., Results: In short eyes, the Hoffer Q had the lowest mean absolute error (MAE) for ALs from 20.00 to 20.99 mm. The Hoffer Q and Holladay 1 had a lower MAE than the SRK/T for ALs from 21.00 to 21.49 mm. There were no statistically significant differences in MAE for ALs from 21.50 to 21.99 mm. In medium eyes, there were no statistically significant differences in MAE for any IOL formula for ALs from 22.00 to 23.49 mm. For ALs from 23.50 to 25.99 mm, there was a trend toward lower MAEs for the Holladay 1, with statistically significant differences in 2 subgroups. In long eyes, the SRK/T had the lowest MAE, with statistically significant differences for ALs of 27.00 mm or longer., Conclusions: The Hoffer Q performed best for ALs from 20.00 to 20.99 mm, the Hoffer Q and Holladay 1 for ALs from 21.00 to 21.49 mm, and the SRK/T for ALs of 27.00 mm or longer. Using optimized constants, refractive outcomes of 40%, 75%, and 95% within ±0.25 diopter (D), ±0.50 D, and ±1.00 D, respectively, were achievable., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. Additional disclosure is found in the footnotes., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Aim: To assess a two-phase method of recording levator function in order to facilitate the identification of patients with ptosis who have a synkinesis between the levator and superior rectus muscles., Methods: 40 consecutive patients who attended oculoplastic clinics with ptosis and 22 patients with normal lid function were recruited. In each subject, levator function was recorded by the conventional method, measuring total upper eyelid excursion between the extremes of down-gaze and up-gaze. Levator function was also assessed using our novel two-phase approach in which upper-eyelid excursion is measured separately between down-gaze and primary position (Phase 1), and between primary position and up-gaze (Phase 2)., Results: In normal patients and most of the patients with ptosis, the majority of lid movement and hence levator function occurs between down-gaze and the primary position (Phase1). In those patients with ptosis and levator-superior rectus synkinesis, a higher proportion of lid movement occurred on up-gaze (Phase2)., Conclusion: The two-phase measurement of lid movement highlights levator function in differing gaze positions and facilitates the identification of those patients with levator-superior rectus synkinesis.

Aims: To derive an evidence base for the efficacy of two novel optometric primary eye care services in Wales, the Primary Eyecare Acute Referral Scheme (PEARS) and the Welsh Eye Health Examination (WEHE)., Methods: A Donabedian model using structure, process and outcome was applied to evaluate prospectively 6432 individuals attending 274 optometrists within an 8-month period. Telephone interviews and review of optometric and hospital notes were used to determine management appropriateness for patients either managed in optometric practice or referred to the Hospital Eye Service (HES). A Geographic Information Systems analysis determined distances travelled to the optometrist. A cost analysis was used to determine the net cost of the schemes., Results: 4243 (66%) of the 6432 individuals were managed in optometric practice; inappropriate management was apparent in 1% of individuals. 392 hospital notes were reviewed; 75% exhibited appropriate optometric referrals to the HES. 87% of individuals travelled less than 5 miles to attend an optometrist. The net cost of a PEARS/WEHE consultation was a minimum of pound12., Conclusions: Optometric management within the schemes is acceptable. Good equity of access was achieved at a relatively low net cost per consultation. Agreement on protocols for referral to the HES would enhance the schemes.

Background: Higher or equal rates of mortality are associated with cataract surgery compared with the general population. Cataract surgery has advanced, and the clinical characteristics of the patient undergoing cataract surgery have changed., Aims: To reinvestigate survival following cataract surgery., Method: Survival data were gathered up to the end of 2006 on 933 consecutive patients who underwent cataract surgery between December 2000 and February 2001. These data were compared with national and regional mortality figures, and standardised mortality ratios (SMR) were calculated., Results: After adjusting for age and sex, there was a statistically significant reduced mortality compared with national (SMR = 0.88 (95% CI 0.79 to 0.99)) and regional figures (SMR = 0.87 (95% CI 0.78 to 0.98))., Conclusion: All previous studies found decreased survival among cataract surgery cohorts. These data differ from data at earlier times, as cataract surgery seems to be associated with increased survival. This illustrates the need for continual re-evaluation of accepted medical knowledge in the light of changes in practice and population demographics.

Aims: To compare the quality of referrals and listing rates of direct optometric referrals vs traditional GP referrals for cataract surgery., Methods: A retrospective cohort of 124 patients referred for cataract surgery was identified (62 via optometric pathway and 62 via GP pathway). The quality of the referral was assessed by establishing if it contained adequate information relating to the College of Optometrists' referral framework document. Age, sex, drug history, listing rate, operative rate, and visual acuity (best corrected) at referral and at the postoperative visit were recorded and compared between the two referral pathways using the Fisher's exact test., Results: Optometric referrals, relative to GP referrals, were more likely to include information relating to objective visual loss (100 vs 87%, P=0.0061) and to counsel the patient (97 vs 18%, P=0.0001). GP referrals, relative to optometric referrals, were more likely to comment on personal circumstances (32 vs 3%, P=0.0001), past medical history (95 vs 68%, P=0.0001), and drug history (94 vs 69%, P=0.0009). Operative rates were higher for the optometric direct referrals relative to GP referrals (87 vs 69%, P=0.0284). There was no difference in the visual acuity before or after surgery between the pathways., Conclusions: Optometric direct cataract referrals provide better information on objectively measured vision and better delivery of preoperative counselling. Traditional GP referrals contain better medical history, drug information, and details of personal circumstances. Rates of surgery were slightly higher with optometric referrals.

Objective: To estimate the distribution and predictors of some common visual problems (strabismus, amblyopia, hypermetropia) within a population-based cohort of children at the age of 7 years., Methods: Children participating in a birth cohort study were examined by orthoptists who carried out cover/uncover, alternate cover, visual acuity and non-cycloplegic refraction tests. Prospectively collected data on potential risk factors were available from the study., Results: Data were available for 7825 seven-year-old children. 2.3% (95% CI 2.0% to 2.7%) had manifest strabismus, 3.6% (95% CI 3.3% to 4.1%) had past/present amblyopia, and 4.8% (95% CI 4.4% to 5.3%) were hypermetropic. Children from the lowest occupational social class background were 1.82 (95% CI 1.03% to 3.23%) times more likely to be hypermetropic than children from the highest social class. Amblyopia (p = 0.089) and convergent strabismus (p = 0.066) also tended to increase as social class decreased., Conclusions: Although strabismus has decreased in the UK, it and amblyopia remain common problems. Children from less advantaged backgrounds were more at risk of hypermetropia and to a lesser extent of amblyopia and convergent strabismus. Children's eye-care services may need to take account of this socio-economic gradient in prevalence to avoid inequity in access to care.

Aim: To evaluate the performance of the frequency doubling technology (FDT) 24-2-5 screening test by comparison with the established N-30-5 FDT screening test for detection of glaucoma., Method: A prospective random sample of individuals referred for possible glaucoma were tested with FDT screening tests 24-2-5 and N-30-5 using the Humphrey Matrix perimeter in addition to standard clinical examination relevant to glaucoma detection. Discriminatory power, reliability and test time of these tests were assessed and compared. The case definition for glaucoma was made by patient according to the established clinical diagnosis., Results: Of 63 referred eligible individuals, 53 (84%) were recruited. Sensitivity and specificity for the N-30-5 screening test was 78 and 85% respectively, compared with 83% and 75% for the 24-2-5 with areas under a receiver operator characteristic curve being 0.87 and 0.92. Differences between these indices were not statistically significant. For a specificity of 95%, sensitivity values were 76% and 56% for the 24-2-5 and N-30-5 respectively. Mean (standard deviation) test duration for the FDT 24-2-5 and N-30-5 screening tests were 111 (13) and 39 (10) seconds respectively (p<0.001). A total of 19 subjects (36%) produced unreliable test results in one or both eyes when tested with the 24-2-5 screening test compared with 5 subjects (9%) with the N-30-5 (p<0.0005)., Conclusion: Minimal discriminatory power differences existed between the two screening tests evaluated, with both screening tests exhibiting high discriminatory power for detection of individuals with glaucoma. More individuals produced unreliable results on the 24-2-5 screening, which also took longer to perform.

Aim: To describe the ultrastructural appearance of explanted opacified Hydroview H60M intraocular lenses., Methods: 14 explanted lenses were examined by scanning electron microscopy, and their appearance compared with a non-implanted H60M lens from the same time period. Wavelength-dispersive x ray spectroscopy (WDX) was performed on two opacified lenses., Results: Subsurface deposits were seen in all explanted opacified lenses. These deposits broke only onto the surface of more densely opacified lenses. WDX confirmed that the deposits contained both calcium and phosphorous, consistent with their being calcium apatite., Conclusion: These findings challenge the widely accepted opinion that H60M intraocular lens opacification begins on the surface of the optic.

Background: Endophthalmitis remains a serious and potentially blinding complication of cataract surgery with an overall incidence of approximately 0.14% or one in 700 operations. Despite this knowledge of overall frequency, healthcare providers find themselves confronted with clusters of cases where the appropriate level of response to the cluster is uncertain., Aim: To illustrate, by means of Monte-Carlo simulation models, the likelihood of random clustering of cases arising in units within a healthcare setting resembling the NHS and separately within the practices of individual surgeons., Method: Simulation models were constructed within a programming language in which individual cataract operations were simulated with a one in 700 likelihood of each operation resulting in a 'case of endophthalmitis'. Random clustering of 'cases of endophthalmitis' was observed in the models and 'outbreaks' were noted and tracked for various outbreak definitions., Results: The model outputs are presented graphically as the proportion of 'simulated units' affected by an 'outbreak' in a year and separately as the proportion of surgeons affected for a range of 'outbreak definitions'., Conclusion: These data presentations are easy to use and should facilitate a better understanding of shifts from endemic to epidemic rates of endophthalmitis with appropriate investigation of situations where a remediable common cause may exist.

Unlabelled: Waterclefts and retrodots are independently associated with visual impairment, yet a review identified no data on risk factors., Purpose: To investigate risk factors for these two human lens cataract subtypes., Method: Two nested case-control studies: The host study comprised 1078 subjects (55 years) attending the Somerset and Avon Eye Study (SAES). In total, 197 watercleft cases (Oxford grade 0.2 in either eye) and 199 retrodot cases (Oxford grade 1.0 in either eye) were individually age/gender matched to controls. Detailed ophthalmic and potential risk factor data were collected, including body mass index (BMI), smoking, alcohol, diabetes, hypertension, analgesics, vitamin supplementation, nutrition, sunlight exposure, dehydration, hormonal (women), blood lipids, glucose, urea, creatinine, uric acid, and vitamin levels., Results: For waterclefts, univariable analysis identified BMI, alcohol intake, vitamin status, sunlight, urea, creatinine, and uric acid as possible risk factors. Multivariable analysis identified two independent associations. Total number of 'any' analgesics in the previous year: adjusted P<0.01 (U-shaped risk profile, unadjusted high vs medium use (=reference) OR 2.39, 95% CI 1.35-4.26 with medium use vs none (=reference) OR 0.43, 95% CI 0.26-0.72); total sunlight: adjusted P=0.03 (unadjusted highest exposure vs lowest (=reference) OR 3.25, 95% CI 1.11-9.50). For retrodots, univariable analysis identified alcohol, HRT, and lipids. Multivariable analysis identified two independent associations. Mean number of alcohol units consumed per month, adjusted P=0.02 and HDL cholesterol levels, adjusted P=0.02 (unadjusted ORs NS both)., Conclusion: This is the first available published information on risk factors for the human cataractous lens features waterclefts and retrodots.

Aims: To evaluate performance of frequency doubling technology (FDT) perimetry using the Humphrey Matrix 24-2 thresholding program in a hospital eye service (HES) glaucoma clinic., Methods: A random sample of individuals referred consecutively to the HES for suspected glaucoma were examined with 24-2 threshold FDT in addition to routine clinical tests. The discriminatory power of FDT and standard automated perimetry (SAP) were assessed using glaucomatous optic nerve head appearance as the reference gold standard., Results: 48 of 62 eligible referred individuals were recruited. Glaucoma prevalence was 31%. Median test duration per eye was 5 minutes 16 seconds for FDT and 5 minutes 9 seconds for SAP. There was no significant difference (p = 0.184) between proportions of individuals with reliable test results (FDT 75%, SAP 63%). Using a clinically appropriate binary criterion for abnormal visual field, sensitivity and specificity levels were 100% and 26% respectively for FDT and 80% and 52% for SAP. Both tests had higher negative than positive predictive values with marginal differences between tests. Criterion free receiver operator characteristic analysis revealed minimal discriminatory power differences., Conclusions: In a HES glaucoma clinic in which new referrals are evaluated, threshold 24-2 FDT testing with the Humphrey Matrix has performance characteristics similar to SAP. These findings suggest threshold testing using the FDT Matrix and SAP is comparable when the 24-2 test pattern is used.

Aim: The primary aim of this large pilot survey was to demonstrate the use and benefits of electronic data collection with respect to rapidly monitoring the access, delivery, and outcome of cataract surgery in the NHS and to update benchmark standards for these parameters of care., Method: Eight NHS departments that currently use specialty-specific electronic clinical systems or Electronic Patient Records (EPR) to collect a minimum preoperative, operative, and anaesthetic data set for cataract surgery agreed to pool their data., Results: A total of 162 surgeons from 50 consultant teams and eight NHS Trusts agreed to submit their data on a total of 16,541 operations for age-related cataract. This report describes the age, sex, and ethnic profiles of the patients, waiting time for surgery, ocular copathology causing a reason for a guarded visual prognosis, visual impairment on admission, visual acuity in the operated eye, and the characteristics of the anaesthetic and surgical procedures., Conclusions: This survey has raised the benchmark standards established by the last National Survey in 1997. There has been a near universal switch to day case, phacosurgery under local anaesthesia (all used in > or =99.1% of cases compared with 70, 77, and 86%, respectively in 1997). The visual impairment in the operated eye is lower with 45% having 6 / 12 or better compared with 27% in 1997. Waiting times and visual impairment in the fellow eye have probably improved although data collection for these variables was incomplete. All departments require specialty-specific clinical systems to efficiently collect and analyse these data and this survey proves their potential to form the basis for national electronic surveys in the future.

Purpose: The aim of this study was to evaluate routine ophthalmic data to identify clinically useful risk factors for progressive visual field loss in patients with primary open-angle glaucoma (POAG) already receiving intraocular pressure-lowering treatments., Methods: A retrospective cohort study design was used. Routine ophthalmic data for all subjects were obtained from case records with the knowledge that baseline clinical data had been collected in a standardised manner. Progression was defined according to the AGIS visual field defect scoring system. Variables evaluated as candidate risk factors for progression were assessed by survival analysis. Factors exerting a significant effect on survival were subsequently tested in a Cox proportional hazards model., Results: A cohort of 108 eligible POAG patients was followed over an average of 3.6 years, with an average visual field intertest interval of 8 months. The incidence rate of progressive loss among the cohort was 5.4 cases per 100 person years. Increasing age was found to be independently associated with a small but significantly increased risk of glaucomatous visual field defect progression (hazard ratio 1.07, P=0.022), and a borderline association was also demonstrated with being male (hazard ratio 2.76, P=0.057)., Conclusions: This retrospective investigation has provided preliminary information on factors associated with increased risk of progressive glaucomatous visual field loss that may inform clinical care strategies. Lack of concordance with other studies suggests that further prospective investigations are needed if risk stratification strategies are to be employed in caring for patients with chronic open-angle glaucoma.

Introduction: The aim of this study was to assess the vision-related quality of life (VR-QOL) in patients with good distance Snellen visual acuity (VA) who are listed for cataract surgery., Methods: An observational cross-sectional prospective study of patients listed for cataract surgery. VA and VR-QOL data using the VCMI questionnaire were collected on patients attending preoperative assessment during June 2002., Results: A total of 397 cataract patients were listed during this month. Following exclusions there were 378 eligible individuals, 210 (56%) of whom had a VA of 6/12 or better in the eye scheduled for surgery. Of these, 40% patients had only mild VR-QOL impairment. More than half of the patients with good VA (6/12 or better) in the surgery eye and mild VR-QOL impairment described their vision as poor in this eye. However, most of these patients were not dissatisfied with their overall level of vision., Conclusion: A significant number of patients listed for cataract surgery with VA of 6/12 or better had only mild VR-QOL impairment and were not dissatisfied with their overall level of vision. The decision to list a patient for surgery may have been based on the patient's perception of monocular vision rather than their quality of life.

Aims: To evaluate the effect of a visual field test educational video on the reliability of the first automated visual field test of new patients., Methods: A prospective, randomised, controlled trial of an educational video on visual field test reliability of patients referred to the hospital eye service for suspected glaucoma was undertaken. Patients were randomised to either watch an educational video or a control group with no video. The video group was shown a 4.5 minute audiovisual presentation to familiarize them with the various aspects of visual field examination with particular emphasis on sources of unreliability. Reliability was determined using standard criteria of fixation loss rate less than 20%, false positive responses less than 33%, and false negative responses less than 33%., Results: 244 patients were recruited; 112 in the video group and 132 in the control group with no significant between group difference in age, sex, and density of field defects. A significant improvement in reliability (p=0.015) was observed in the group exposed to the video with 85 (75.9%) patients having reliable results compared to 81 (61.4%) in the control group. The difference was not significant for the right (first tested) eye with 93 (83.0%) of the visual fields reliable in the video group compared to 106 (80.0%) in the control group (p = 0.583), but was significant for the left (second tested) eye with 97 (86.6 %) of the video group reliable versus 97 (73.5%) of the control group (p = 0.011)., Conclusions: The use of a brief, audiovisual patient information guide on taking the visual field test produced an improvement in patient reliability for individuals tested for the first time. In this trial the use of the video had most of its impact by reducing the number of unreliable fields from the second tested eye.

The aim of the study was to develop a new questionnaire to assess visual symptoms/dysfunction and impact on vision-specific quality of life for those undergoing second eye cataract extraction. Items for the VSQ questionnaire were devised with reference to existing literature and following consultation with eye care experts (n = 18) and interviews with cataract patients (n = 40). Piloting work conducted with 53 patients indicated that the questionnaire was promising, with a high level of internal consistency, low levels of missing data and indications that it was responsive to surgery. A modified version of the questionnaire was completed by 105 patients having received 'early' surgery and 103 scheduled for routine surgery within a randomised controlled trial evaluating the effectiveness of second eye cataract surgery. Analyses showed that the internal consistency of both the visual symptoms/dysfunction and quality of life areas was high (Cronbach's alpha 0.82 and 0.83, respectively). Highly significant improvements were found for early surgery patients (p < 0.0001), with little change among routine surgery patients. Two final versions of the VSQ questionnaire have been produced for future use in assessing visual symptoms/dysfunction and impact on vision-specific quality of life: a scoreable short form and more detailed and sensitive long form.

Purpose: This national study was designed to audit anatomical outcome and complications relating to primary surgery for rhegmatogenous retinal detachments. This paper presents survey methods, characteristics of participating consultants and the demographic and clinical characteristics of the patient sample., Methods: Two surveys were undertaken. The first identified consultants who at the time performed retinal detachment surgery in the National Health Service. These surgeons formed the sampling frame for a nationwide cross-sectional clinical study that audited the outcomes of primary surgery for rhegmatogenous retinal detachments. Consultants selected patients according to the study eligibility criteria and data were collected by self-administered postal questionnaires. A validation exercise was carried out to examine selection bias and reporting accuracy., Results: Only 256/671 (38%) of UK consultants, who responded to the first survey, indicated that they performed retinal detachment surgery on NHS patients. Annual activity varied between 0 and 400 primary procedures for rhegmatogenous retinal detachments. Seven hundred and sixty-eight eligible patients from 167 consultants were recruited for the clinical study. Twenty per cent of patients had a single retinal break with less than one quadrant of associated detachment and 45% had single or multiple breaks within the same quadrant and/or less than two quadrants of associated retinal detachment. Over 50% patients had single or multiple horseshoe tears. Validation studies suggested that there was no significant bias from the selection of patients or inaccuracy in reporting outcomes., Conclusions: This large unselected group of primary rhegmatogenous retinal detachments provides a representative sample for considering variations in re-attachment rates.

Purpose: This national study was designed to audit anatomical outcome and complications relating to primary surgery for rhegmatogenous retinal detachments. This paper presents success and complication rates, and examines variations in outcome., Methods: Sampling and recruitment details of this nationwide cross-sectional survey of 768 patients of 167 consultant ophthalmologists having their first operation for rhegmatogenous retinal detachment have been described. The main clinical outcomes detailed here are anatomical reattachment at 3 months after surgery and complications related to surgery. Consultants with a declared special interest in retinal surgery and able to perform pars plana vitrectomy were designated specialists for the analyses., Results: Overall reattachment rate with a single procedure was 77% (95% CI 73.9-80.2). There were significant differences in reattachment rates between specialists and non-specialists. Without allowing for case-mix, specialists had a reattachment rate of 82% (95% CI 77.9-85.7) with a single procedure and non-specialists 71% (95% CI 65.9-76.0). Allowing for case-mix, there was a significant difference between specialists and non-specialists for grade 2 detachments of 87% and 70% respectively (P < 0.0001). Analysing detachments by break type, the largest difference between specialists and non-specialists was observed for retinal detachments secondary to horseshoe tears, 80% and 68% respectively (P < 0.003). Specialists met the standards set for primary reattachment rates, while non-specialists did not. Over a third of patients had at least one complication reported at some point during the audit period., Conclusions: Significant differences were seen in reattachment rates between specialists and non-specialists, overall and for specific subgroups of patients. This study provides relevant, robust and valid standards to enable all surgeons to audit their own surgical outcomes for primary retinal detachment repair in rhegmatogenous retinal detachments, identify common categories of failure and aim to improve results.

Purpose: To investigate the relationships between visual acuity, contrast sensitivity, and 11 clinicopathologic classes of opacity in the human crystalline lens., Methods: The Somerset and Avon Eye Study is an observational population study of age-related sight-threatening eye disease, based in Bristol, UK. After excluding eyes with other visually relevant disease, data from 902 individuals aged 55 years or older were analyzed. The associations of lens features (posterior subcapsular cataract, nuclear color, nuclear white scatter, cortical spokes, anterior subcapsular cataract, vacuoles, waterclefts, coronary flakes, focal dots, retrodots, fiber folds), with refracted log minimum angle of resolution (MAR) distance acuity and Pelli-Robson contrast sensitivity, were investigated. Multivariable linear regression models using data from both eyes and taking account of the intraclass correlation between eyes were used for analysis, with the lens features and age included as potential explanatory variables., Results: As anticipated from earlier studies, posterior subcapsular, nuclear, and cortical cataracts were associated with visual impairment. In addition, retrodots were strongly and independently associated in the multivariable models with both impaired visual acuity (P < 0.001) and contrast sensitivity (P < 0.001). Waterclefts were strongly associated with impaired visual acuity (P < 0.001)., Conclusions: Retrodots and waterclefts are associated with visual impairment. A causal relationship between these lens features and retinal image degradation is plausible.

Objective: To assess the effectiveness of early treatment for amblyopia in children., Design: Follow up of outcomes of treatment for amblyopia in a randomised controlled trial comparing intensive orthoptic screening at 8, 12, 18, 25, 31, and 37 months (intensive group) with orthoptic screening at 37 months only (control group)., Setting: Avon, southwest England., Participants: 3490 children who were part of a birth cohort study., Main Outcome Measures: Prevalence of amblyopia and visual acuity of the worse seeing eye at 7.5 years of age., Results: Amblyopia at 7.5 years was less prevalent in the intensive group than in the control group (0.6% v 1.8%; P=0.02). Mean visual acuities in the worse seeing eye were better for children who had been treated for amblyopia in the intensive group than for similar children in the control group (0.15 v 0.26 LogMAR units; P<0.001). A higher proportion of the children who were treated for amblyopia had been seen in a hospital eye clinic before 3 years of age in the intensive group than in the control group (48% v 13%; P=0.0002)., Conclusions: The intensive screening protocol was associated with better acuity in the amblyopic eye and a lower prevalence of amblyopia at 7.5 years of age, in comparison with screening at 37 months only. These data support the hypothesis that early treatment for amblyopia leads to a better outcome than later treatment and may act as a stimulus for research into feasible screening programmes.

Aim: To evaluate the correlation between internal slope analysis of the optic nerve head and visual field changes in normal eyes and those with ocular hypertension (OHT) and early glaucoma (POAG)., Methods: One eye of each of 22 normal subjects, 21 patients with ocular hypertension, and 50 patients with glaucoma were examined using the TopSS scanning laser ophthalmoscope. A series of topographic parameters measuring the internal features of the optic discs of these patients were obtained. These findings were compared with the Humphrey visual field analysis of these patients., Results: Global topographic average slope and cup to disc ratio could discriminate between groups of normal and OHT patients (p = 0.02). All global and sector analysis parameters could discriminate normal subjects from POAG patients. The average slope parameter provided the best separation with a receiver operating characteristic curve area of 0.88. Visual field mean deviation (MD) was most closely correlated with global average slope (r = -0.60, p<10(-7)) and cup to disc ratio (r = -0.40, p<0.001). Visual field MD was also well correlated (r = -0.50, p<0.0001) with slope parameters for sectors S8, S2, and S1., Conclusion: Average slope, a parameter independent of reference planes and magnification effects, is capable of discriminating groups of OHT and POAG patients from a group of normal subjects. This topographic parameter is also well correlated with the visual field MD. Sector slope analysis suggests early glaucomatous damage may occur in the inferotemporal region of the optic disc.

Purpose: To describe the level of co-morbidity in patients with sight-threatening diabetic retinopathy in the United Kingdom., Methods: Questionnaires were completed by patients undergoing first photocoagulation treatment for diabetic maculopathy or proliferative retinopathy during a 2 month period throughout the UK., Results: Overall 15% of patients described angina, 9% had suffered a myocardial infarction and 6% a stroke. Self-reported renal disease was present in 8.5%. Foot ulceration was described by 10% of patients, and 4% had undergone an amputation. 35.5% of patients were on treatment for hypertension. 17.5% of patients had been hospitalised in the previous 6 months, and 3% of patients had died within 9 months of the laser treatment., Conclusions: There was significant co-morbidity in these patients, which may affect the management of their retinopathy.

Introduction: The rationale for preschool vision screening programmes has recently been questioned. Evidence about the effects of early treatment is needed, but it is not known how early the target conditions can reliably be detected. In this study, an intensive programme comprising several different screening methods, used at different ages up to 37 months, was compared with the usual practice of visual surveillance and ad hoc referrals., Methods: Two groups were randomly selected from children in a population birth cohort study. The control group (n = 1461) received visual surveillance only. The intervention group (n = 2029) was offered in addition a programme of regular visual assessments by orthoptists testing visual acuity, ocular alignment, stereopsis and non-cycloplegic photorefraction., Results: The intervention group programme yielded more children with amblyopia (1.6% vs. 0.5%, p < 0.01), and was more specific (95% vs. 92%, p < 0.01), than the control programme. The individual components of the intervention programme were compared. The cover test and visual acuity tests were poorly sensitive until the children were 37 months, but were always >99% specific. Photorefraction was more sensitive than acuity testing at all ages below 37 months, with specificity >95% at 31 and 37 months., Conclusions: Photorefraction would have detected more children less than 37 months of age with straight-eyed amblyopia than did visual acuity testing, but with more false positives. At 37 months, photorefraction plus a cover test would have been comparable in effectiveness to visual acuity testing plus a cover test.

Aims: To assess the level of visual symptomatology in patients with sight-threatening diabetic retinopathy., Methods: Questionnaires were completed by patients undergoing first photocoagulation treatment for diabetic maculopathy or proliferative retinopathy during a 2-month period throughout the UK, and at 9 months' follow-up., Results: There were high levels of visual symptomatology prior to the first laser treatment and at follow-up for both patients with maculopathy or with proliferative retinopathy. Only 25.1% of patients with maculopathy and 17.2% of patients with proliferative retinopathy were asymptomatic in terms of reading, seeing the television screen, recognizing faces or with their night vision at baseline. For those with maculopathy 20.1% were aware of colour vision abnormality in the eye to be treated at baseline and 9.5% were aware of new central scotomata since the treatment. Of those with proliferative retinopathy, 13% said that they had given up driving due to poor eyesight and 19% were aware of new peripheral field defects since the treatment., Conclusions: There are high levels of visual symptomatology for patients with sight-threatening diabetic retinopathy in the UK despite that fact that screening should aim to detect retinopathy prior to visual loss occurring. Patients should be aware that there may not be any significant improvement in their vision with laser treatment, and that the main aim of treatment is to reduce the likelihood of further visual deterioration.

Aim: To investigate the examination of lens opacities in routine ophthalmic clinical practice., Method: A questionnaire survey was mailed to 703 consultant ophthalmologists in the UK. The surgeons were asked which lens feature(s) they assessed in their clinics when deciding whether to offer cataract surgery., Results: 489 replies were received. A broad range of lens opacities was assessed, with differences between surgeons for some opacities with high prevalences in the population, particularly cortical opacities. Many (74% of 467) surgeons assessed one or more lens opacities (anterior subcapsular cataract, vacuoles, water clefts, coronary flakes, focal dots, retrodots, fibre folds) which may be visually important but which have received relatively little attention by researchers., Conclusions: Some classes of lens opacity which are traditionally measured by researchers may be ignored in clinical practice and opacities which are traditionally ignored by some researchers are regarded as clinically important by a substantial number of surgeons.

Purpose: To assess the reliability of different methods of administration of the VCM1 vision-related quality-of-life questionnaire by: a) comparing responses obtained by post to responses obtained in a research clinic and b) comparing responses obtained by telephone to responses obtained in a research clinic., Method: Questionnaire responses given in advance by post (96 subjects) or by telephone (92 subjects) were compared to those subsequently given at a visit to a research clinic. The questionnaire included the VCM1 and two other questions commonly used in surveys of visual impairment (reading small print and recognising a face across the street)., Results: Similar levels of vision-related quality-of-life (VR-QOL) impairment were reported by post and in the research clinic. However, the participants in the telephone test group reported less VR-QOL impairment by telephone than they subsequently reported in the clinic (P = 0.0001). The mean score difference between telephone and clinic administration was 3.2% of the VCM1 questionnaire scale. Lower social class (P = 0.002) and increasing duration of interview (P = 0.003) were associated with a tendency to under-report VR-QOL impairment by telephone. Interference with reading small print (P = 0.0001) and recognising a face across the street (P = 0.0001) were also under-reported by telephone., Conclusions: Telephone interviewing caused a general bias towards under-reporting of visual problems which was not confined to the VCM1. Care is required when planning outcome studies and questionnaire surveys to ensure that different methods of questionnaire administration produce comparable results.

Purpose: The aim of this study is to describe and compare test-retest variability of threshold-related suprathreshold and threshold examination strategies., Methods: Threshold-related suprathreshold and FASTPAC threshold central visual field examinations were performed twice (test and retest) within a 4-week period on 322 subjects with early to moderate primary open-angle glaucoma and glaucoma suspects. For both strategies, defects were quantified by a count, or score, of the number of defective locations within the field as a whole and by hemifield, thereby providing a simple measure of defect extent. This quantification was obtained for the suprathreshold strategy at three suprathreshold increments (5, 8, and 12 dB) and for the full threshold strategy at two levels of pattern deviation probability, although absolute full threshold defect depth was not considered. Mean test-retest score differences and spread of score differences were used to describe variability. An index of relative variability was used to compare the two visual field examination strategies., Results: Marked degrees of defect extent variability were found to exist in both suprathreshold and FASTPAC examination strategies. In general, the suprathreshold strategy exhibited lower test-retest variability of defect extent than the FASTPAC strategy. Suprathreshold test variability was dependent on the suprathreshold increment. FASTPAC examination variability was independent of defect depth when analyzed on the basis of pattern deviation probability values and was also found to be independent of the area of visual field loss., Conclusions: Suprathreshold examination techniques may provide a reliable perimetric alternative to thresholding strategies for monitoring individuals with early and moderate glaucoma, although they may not be suitable for individuals with advanced glaucomatous visual field loss.

Aim: To examine the outcome of care for patients with glaucoma followed up by the hospital eye service compared with those followed up by community optometrists., Methods: A randomised study with patients allocated to follow up by the hospital eye service or community optometrists was carried out in the former county of Avon in south west England. 403 patients with established or suspected primary open angle glaucoma attending Bristol Eye Hospital and meeting defined inclusion and exclusion criteria were studied. The mean number of missed points on visual field testing in the better eye (using a "better/worse" eye analysis) in each group were measured. The visual field was measured using the Henson semiautomated central field analyser (CFA 3000). Measurements were made by the research team on all patients at baseline before randomisation and again 2 years after randomisation. The mean number of missed points on visual field testing in the worse eye, mean intraocular pressure (mm Hg), and cup disc ratio using a "better/worse" eye analysis in each group at 2 years were also measured. Measurements were made by the research team on all patients at baseline before randomisation and again 2 years after randomisation. An analysis of covariance comparing method of follow up taking into account baseline measurements of outcome variables was carried out. Additional control was considered for age, sex, diagnostic group (glaucoma suspect/established primary open angle glaucoma), and treatment (any/none)., Results: From examination of patient notes, 2780 patients with established or suspected glaucoma were identified. Of these, 752 (27.1%) fulfilled the entry criteria. For hospital and community follow up group respectively, mean number of missed points on visual field testing at 2 year follow up for better eye was 7.9 points and 6.8 points; for the worse eye 20.2 points and 18.4 points. Similarly, intraocular pressure was 19.3 mm Hg and 19.3 mm Hg (better eye), and 19.1 mm Hg and 19.0 mm Hg (worse eye); cup disc ratio at 2 year follow up was 0.72 and 0.72 (better eye), and 0.74 and 0.74 for hospital and community follow up group respectively. No significant differences in any of the key visual variables were found between the two groups before or after adjusting for baseline values and age, sex, treatment, and type of glaucoma., Conclusions: It is feasible to set and run shared care schemes for a proportion of patients with suspected and established glaucoma using community optometrists. After 2 years (a relatively short time in the life of a patient with glaucoma), there were no marked or statistically significant differences in outcome between patients followed up in the hospital eye service or by community optometrists. Decisions to implement such schemes need to be based on careful consideration of the costs of such schemes and local circumstances, including geographical access and the current organisation of glaucoma care within the hospital eye service.

Aim: To provide information on the use of vision tests in clinical decision making about cataract surgery in the UK., Method: A questionnaire survey was mailed to 703 consultant ophthalmologists., Results: A response rate of 70% was obtained. Monocular distance visual acuity was the only visual function that was tested routinely by all surgeons. Supplementary use of contrast sensitivity and glare testing was low. Many surgeons (35%) were willing to consider surgery at acuity levels better than 6/9 and a small but substantial number (12%) indicated that they did not use an acuity criterion. Being prepared to consider surgery at relatively good levels of acuity was not associated with more common use of other tests of vision., Conclusion: Many UK surgeons are prepared to consider cataract extraction at relatively good levels of visual acuity and use other vision tests infrequently.

Purpose: The PR2000 (Topcon, Tokyo, Japan) is a photorefractor that has been used in a population study comparing different methods of screening preschool children. The present study was conducted to determine the accuracy of the device in a largely clinical population., Methods: Two hundred twenty-two children less than 8 years of age were included. All children were examined by an orthoptist using the PR2000 without inducing cycloplegia. All children then underwent retinoscopy with cycloplegia by an examiner who was unaware of the results from the PR2000 examination., Results: The PR2000 gave a numerical reading for 90% of the children's right eyes and the message "Out of range" for a further 5%. The readings underestimated the amount of hypermetropic or astigmatic refractive error found on retinoscopy by an amount proportional to the magnitude of the refractive error. Agreement with retinoscopy for the axis of astigmatism more than 0.75 D was moderately good (intraclass correlation coefficient [ICC] = 0.63). The PR2000 was more useful as a screener, especially for anisometropia for which it was 91% sensitive and 92% specific. The repeatability was good for sphere (ICC = 0.74), less so for astigmatism (ICC = 0.59), and better than the optometrist for anisometropia (ICC = 0.38). The presence of nonrefractive diagnoses and the age of the children examined made little difference in the screening results., Conclusions: The PR2000 underestimated hypermetropic refractive errors when used without cycloplegia. However, it was at least as good a screening device as other similar instruments, especially when judged by its ability to detect anisometropia and the repeatability of the results.