UNITED KINGDOM DATABASE STUDY OF INTRAVITREAL DEXAMETHASONE IMPLANT (OZURDEX) FOR MACULAR EDEMA RELATED TO RETINAL VEIN OCCLUSION.

PURPOSE: To study the treatment patterns, visual outcomes and safety profile of intravitreal dexamethasone implant (IDI) used for the treatment of macular edema secondary to retinal vein occlusion. METHODS: Up to 2 years of routinely collected anonymized data within electronic medical record systems were remotely extracted from 16 centers. The outcome measures include visual outcome, number of injections, and safety measures, including the rate of intraocular pressure (IOP) rise, frequency of IOP-lowering medication usage, and cataract surgery rates. RESULTS: The study included 688 eyes (44.4%) with central retinal vein occlusion and 862 eyes (55.6%) with branch retinal vein occlusion; 1,250 eyes (80.6%) were treatment naive and 28% (275/989) had high IOP or were on IOP-lowering medications before IDI use. It was found that 31% (476) of eyes received two injections, and 11.7% (182) and 3.7% (58) of eyes received three and four injections, respectively. The mean baseline Snellen visual acuity improved from 20/125 to 20/40 after the first injection. The probability of cataract surgery was 15% at 24 months. The proportion of eyes with ≥10 mmHg change from baseline was higher in phakic (14.2%) compared with pseudophakic eyes (5.4%, P = 0.004). Three eyes required IOP filtering surgery (0.2%). CONCLUSION: The visual results of IDI in eyes with macular edema secondary to retinal vein occlusion in the real world are comparable to those of clinical trial setting. Increased IOP in eyes with preexisting ocular hypertension or glaucoma can be controlled with additional medical treatment. Intraocular pressure rise with IDI may be more frequent in phakic than in pseudophakic eyes.

Progression from Early/Intermediate to Advanced Forms of Age-Related Macular Degeneration in a Large UK Cohort: Rates and Risk Factors.

PURPOSE: To estimate rates and risk factors for progression to geographic atrophy (GA) or choroidal neovascularization (CNV) among eyes diagnosed with early or intermediate age-related macular degeneration (AMD) in clinical practice. DESIGN: Retrospective cohort analysis of a multicenter electronic medical record (EMR) database from the United Kingdom. PARTICIPANTS: Patients aged 50 years or more with diagnosis of early/intermediate AMD in at least 1 eye (the study eye) and no evidence of CNV or GA in the study eye, from 10 clinical sites using the EMR. METHODS: Anonymized data for 40 543 patients with a diagnosis of early/intermediate AMD were extracted between October 2000 and February 2016 from EMR database records held in the 10 sites. A sample of records randomly selected from each center was used to validate disease definitions. Records were analyzed by subgroup, based on the AMD status of the fellow eye. Multivariate Cox regression models identified other predictors of disease progression. MAIN OUTCOME MEASURES: Progression rate (per 100 person-years) to GA or CNV in study eyes with early/intermediate AMD by fellow eye status and identified risk factors for progression. RESULTS: Study eyes with early/intermediate AMD and a diagnosis of CNV in the fellow eye progressed to CNV fastest (at a rate of 15.2 per 100 person-years), and those with a diagnosis of GA in the fellow eye progressed to GA fastest (11.2 per 100 person-years), compared with the rates per 100 person-years of progression to CNV (3.2-11.9) or GA (2.0-7.8) in the other subgroups. In individuals with bilateral early/intermediate AMD, rates of progression to GA or CNV were 2.0 and 3.2 per 100 person-years, respectively. In the multivariate model, age, female sex, and cardiovascular disease were associated with an increased risk for progression to advanced AMD, whereas diabetes and glaucoma were associated with a decreased rate of progression (hazard ratios, 0.45 and 0.64, respectively). CONCLUSIONS: Progression to GA or CNV was observed frequently in eyes with early/intermediate AMD, with the status of the fellow eye affecting the rate of progression. Novel associations with risk factors were observed and require replication in other cohorts.

Direct Ophthalmic Healthcare Resource Use among Patients with Geographic Atrophy in a Large Cohort from the United Kingdom.

PURPOSE: To estimate the direct ophthalmic healthcare resource use in patients with geographic atrophy (GA) secondary to age-related macular degeneration (AMD). DESIGN: Retrospective analysis of anonymized data derived from electronic medical records (EMRs) acquired at 10 clinical sites in the United Kingdom. PARTICIPANTS: Patients aged ≥50 years with ≥1 eye with a clinical record of GA or, for comparison, bilateral early/intermediate AMD. Four subgroups were identified: GA in both eyes (GA:GA); GA in 1 eye, choroidal neovascularization (CNV) in the fellow eye (GA:CNV); GA in 1 eye with early or intermediate AMD in the fellow eye (GA:E); and early/intermediate AMD in both eyes (E:E). METHODS: The EMRs were analyzed to derive the median number of visits over the first 2 years after diagnosis of GA or early/intermediate AMD. Clinical tests recorded at visits were used to calculate estimated costs (payer perspective) of monitoring. Analyses were restricted to patients with an initial diagnosis on or after January 1, 2011, to represent present day monitoring and costs associated with AMD. MAIN OUTCOME MEASURES: Median number of visits and estimated monitoring costs per patient (in £) over the first 2 years among patients with ≥2 years of follow-up and in the individual subgroups. Intravitreal treatment costs in the GA:CNV group were excluded. RESULTS: For all 3 GA subgroups (n = 1080), the median number of visits over the first 2 years was 5, and monitoring costs were £460.80 per patient. The GA:CNV subgroup (n = 355) had the highest number of visits (median, 15), with a cost of £1581, compared with the GA:E subgroup (n = 283; median 4 visits; cost ∼£369) and the GA:GA subgroup (n = 442; median 3 visits; cost ∼£277). Ophthalmic tests were conducted most frequently in the GA:CNV subgroup. Visits and costs in the E:E subgroup (n = 6079) were lower. CONCLUSIONS: Resource use in patients with GA varies considerably and is strongly influenced by the concomitant presence of CNV and lack of monitoring strategies for GA.

United Kingdom Diabetic Retinopathy Electronic Medical Record (UK DR EMR) Users Group: report 4, real-world data on the impact of deprivation on the presentation of diabetic eye disease at hospital services.

AIM: To assess the impact of deprivation on diabetic retinopathy presentation and related treatment interventions, as observed within the UK hospital eye service. METHODS: This is a multicentre, national diabetic retinopathy database study with anonymised data extraction across 22 centres from an electronic medical record system. The following were the inclusion criteria: all patients with diabetes and a recorded, structured diabetic retinopathy grade. The minimum data set included, for baseline, age and Index of Multiple Deprivation, based on residential postcode; and for all time points, visual acuity, ETDRS grading of retinopathy and maculopathy, and interventions (laser, intravitreal therapies and surgery). The main  outcome measures were (1) visual acuity and binocular visual state, and (2) presence of sight-threatening complications and need for early treatment. RESULTS: 79 775 patients met the inclusion criteria. Deprivation was associated with later presentation in patients with diabetic eye disease: the OR of being sight-impaired at entry into the hospital eye service (defined as 6/18 to better than 3/60 in the better seeing eye) was 1.29 (95% CI 1.20 to 1.39) for the most deprived decile vs 0.77 (95% CI 0.70 to 0.86) for the least deprived decile; the OR for being severely sight-impaired (3/60 or worse in the better seeing eye) was 1.17 (95% CI 0.90 to 1.55) for the most deprived decile vs 0.88 (95% CI 0.61 to 1.27) for the least deprived decile (reference=fifth decile in all cases). There is also variation in sight-threatening complications at presentation and treatment undertaken: the least deprived deciles had lower chance of having a tractional retinal detachment (OR=0.48 and 0.58 for deciles 9 and 10, 95% CI 0.24 to 0.90 and 0.29 to 1.09, respectively); in terms of accessing treatment, the rate of having a vitrectomy was lowest in the most deprived cohort (OR=0.34, 95% CI 0.19 to 0.58). CONCLUSIONS: This large real-world study suggests that first presentation at a hospital eye clinic with visual loss or sight-threatening diabetic eye disease is associated with deprivation. These initial hospital visits represent the first opportunities to receive treatment and to formally engage with support services. Such patients are more likely to be sight-impaired or severely sight-impaired at presentation, and may need additional resources to engage with the hospital eye services over complex treatment schedules.

IRay therapy as an adjuvant therapy in newly diagnosed patients with neovascular age-related macular degeneration.

OBJECTIVES: To determine the safety and efficacy at 12 months of follow-up after stereotactic radiotherapy in combination therapy with intravitreal ranibizumab injections in treatment naïve patients with neovascular age-related macular degeneration. METHODS: Retrospective data analysis in patients who received stereotactic radiotherapy (IRay Therapy) during the induction phase of intravitreal ranibizumab injections and a monotherapy control group. RESULTS: The baseline VA in the IRay and control group was 59.87 and 59.12 letters respectively. The real world visual acuity outcomes for the IRay group showed a mean gain of +3.0 letters at 12 months. The historical control group had a mean change of - 0.3 letters. The average number of injections for the IRay group and control group over 12 months was 4.45 and 5.64, respectively with three loading injections. Excluding the loading phase, the difference over 12 months was a 45.2% reduction in injections (P < 0.001). The number of subjects in the IRay group that didn't require further injections following the loading phase was 45.5 vs. 24.0% control group (P = 0.005). The difference in mean change in central macular thickness from baseline is significant at 6 (P = 0.010) and 12 months (P < 0.01). There were no safety concerns with the IRay therapy group. CONCLUSIONS: Stereotactic radiotherapy in the induction phase of intravitreal injections of ranibizumab for treatment naïve patients with neovascular age-related macular degeneration, resulted in improved visual outcome, statistically fewer injections and statistically drier macular at 12 months, compared to historical controls treated with monotherapy intravitreal ranibizumab injections.

Characterizing Disease Burden and Progression of Geographic Atrophy Secondary to Age-Related Macular Degeneration.

PURPOSE: To understand levels of disease burden and progression in a real-world setting among patients from the United Kingdom with bilateral geographic atrophy (GA) secondary to age-related macular degeneration (AMD). DESIGN: Retrospective cohort analysis of a multicenter electronic medical record (EMR) database. PARTICIPANTS: Patients who were aged ≥50 years with bilateral GA and no history of choroidal neovascularization (CNV) and who attended 1 of 10 clinical sites using the EMR. METHODS: A deidentified data set was constructed from the records held at the 10 sites. An algorithm was used to extract cases with a GA diagnosis, of which 1901 had bilateral GA and form the basis of this report. A sample of records randomly selected from each center was used to validate disease definitions. MAIN OUTCOME MEASURES: Progression to blindness (visual acuity [VA] <20 letters or Snellen 3/60 in the better-seeing eye), driving ineligibility (VA ≤70 letters or Snellen 6/12 in the better-seeing eye), progression to CNV, loss of 10 or more letters, and mean change in VA over time. RESULTS: At first record of GA, 7.1% had a VA in the better-seeing eye equal to or lower than the cutoff for blindness registration and 71.1% had a VA that would have rendered them ineligible to drive. Over time, 16% became legally blind (median time to outcome, 6.2 years) and 66.7% became ineligible to drive (median time to outcome, 1.6 years). In the worse-seeing eye, 40.1% lost ≥10 letters in 2.4 years. Among patients with baseline and 24-month VA measurements, mean VA decline was 6.1 letters in the worse-seeing eye (n = 413) and 12.4 letters in the better-seeing eye (n = 414). The rate of progression to CNV in either eye was 7.4% per patient-year. CONCLUSIONS: At initial diagnosis, based on VA in the better-seeing eye, a high proportion of patients with bilateral GA were ineligible to drive and approximately 7% were eligible for UK blindness registration. The subsequent reduction in VA that occurred in the better-seeing eye would render a further two-thirds ineligible to drive. These findings emphasize the severity of the visual disability associated with GA secondary to AMD.

VISUAL ACUITY IMPROVEMENT WHEN SWITCHING FROM RANIBIZUMAB TO AFLIBERCEPT IS NOT SUSTAINED.

PURPOSE: To assess whether visual benefits exist in switching to aflibercept in patients who have been chronically treated with ranibizumab for neovascular age-related macular degeneration. METHODS: A multicenter, national, electronic medical record database study was performed. Patients undergoing six continuous monthly ranibizumab injections and then switched to continuous aflibercept were matched to those on continuous ranibizumab therapy. Matching was performed in a 2:1 ratio and based on visual acuity 6 months before and at the time of the switch, and the number of previous ranibizumab injections. RESULTS: Patients who were switched to aflibercept demonstrated transiently significant improvement in visual acuity that peaked at an increase of 0.9 Early Treatment Diabetic Retinopathy Study letters 3 months after the switch, whereas control patients continued on ranibizumab treatment showed a steady decline in visual acuity. Visual acuity differences between the groups were significant (P < 0.05) at 2, 3, and 5 months after the switch. Beginning at 4 months after the switch, the switch group showed a visual acuity decline similar to the control group. CONCLUSION: Transient, nonsustained improvement in visual acuity occurs when switching between anti-vascular endothelial growth factor agents, which may have implications in treating patients on chronic maintenance therapy on one anti-vascular endothelial growth factor medication.

The United Kingdom Diabetic Retinopathy Electronic Medical Record Users Group: Report 3: Baseline Retinopathy and Clinical Features Predict Progression of Diabetic Retinopathy.

PURPOSE: To determine the time and risk factors for developing proliferative diabetic retinopathy (PDR) and vitreous hemorrhage (VH). DESIGN: Multicenter, national cohort study. METHODS: Anonymized data of 50 254 patient eyes with diabetes mellitus at 19 UK hospital eye services were extracted at the initial and follow-up visits between 2007 and 2014. Time to progression of PDR and VH were calculated with Cox regression after stratifying by baseline diabetic retinopathy (DR) severity and adjusting for age, sex, race, and starting visual acuity. RESULTS: Progression to PDR in 5 years differed by baseline DR: no DR (2.2%), mild (13.0%), moderate (27.2%), severe nonproliferative diabetic retinopathy (NPDR) (45.5%). Similarly, 5-year progression to VH varied by baseline DR: no DR (1.1%), mild (2.9%), moderate (7.3%), severe NPDR (9.8%). Compared with no DR, the patient eyes that presented with mild, moderate, and severe NPDR were 6.71, 14.80, and 28.19 times more likely to develop PDR, respectively. In comparison to no DR, the eyes with mild, moderate, and severe NPDR were 2.56, 5.60, and 7.29 times more likely to develop VH, respectively. In severe NPDR, the eyes with intraretinal microvascular abnormalities (IRMA) had a significantly increased hazard ratio (HR) of developing PDR (HR 1.77, 95% confidence interval [CI] 1.25-2.49, P = .0013) compared with those with venous beading, whereas those with 4-quadrant dot-blot hemorrhages (4Q DBH) had 3.84 higher HR of developing VH (95% CI 1.39-10.62, P = .0095). CONCLUSIONS: Baseline severities and features of initial DR are prognostic for PDR development. IRMA increases risk of PDR whereas 4Q DBH increases risk of VH.

The UK Diabetic Retinopathy Electronic Medical Record (UK DR EMR) Users Group, Report 2: real-world data for the impact of cataract surgery on diabetic macular oedema.

AIM: To assess the rate of 'treatment-requiring diabetic macular oedema (DMO)' in eyes for the two years before and after cataract surgery. METHODS: Multicentre national diabetic retinopathy (DR) database study with anonymised data extraction across 19 centres from an electronic medical record system. INCLUSION CRITERIA: eyes undergoing cataract surgery in patients with diabetes with no history of DMO prior to study start. The minimum dataset included: age, visual acuity (all time-points), injection episodes, timing of cataract surgery and ETDRS grading of retinopathy and maculopathy. MAIN OUTCOME MEASURE: rate of developing first episode of treatment-requiring DMO in relation to timing of cataract surgery in the same eye. RESULTS: 4850 eyes met the inclusion criteria. The rate of developing treatment-requiring DMO in this cohort was 2.9% in the year prior to surgery versus 5.3% in the year after surgery (p<0.01). The risk of 'treatment-requiring DMO' increased sharply after surgery, peaking in the 3-6 months' period (annualised rates of 5.2%, 6.8%, 5.6% and 4.0% for the 0-3, 3-6, 6-9 and 9-12 months' post-operative time periods respectively). Risk was associated with pre-operative grade of retinopathy: risk of DMO in the first year post-operatively being 1.0% (no DR pre-operatively), 5.4% (mild non-proliferative diabetic retinopathy; NPDR), 10.0% (moderate NPDR), 13.1% (severe NPDR) and 4.9% (PDR) (p<0.01). CONCLUSIONS: This large real-world study demonstrates that the rate of developing treatment-requiring DMO increases sharply in the year after cataract surgery for all grades of retinopathy, peaking in the 3-6 months' postoperative period. Patients with moderate and severe NPDR are at particularly high risk.

UK AMD/DR EMR REPORT IX: comparative effectiveness of predominantly as needed (PRN) ranibizumab versus continuous aflibercept in UK clinical practice.

AIMS: To compare the effectiveness of continuous aflibercept versus pro re nata (PRN) ranibizumab therapy for neovascular age-related macular degeneration (nAMD). METHODS: Multicentre, national electronic medical record (EMR) study on treatment naive nAMD eyes undergoing PRN ranibizumab or continuous (fixed or treat and extend (F/TE)) aflibercept from 21 UK hospitals. Anonymised data were extracted, and eyes were matched on age, gender, starting visual acuity (VA) and year of starting treatment. Primary outcome was change in vision at 1 year. RESULTS: 1884 eyes (942 eyes in each group) were included. At year 1, patients on PRN ranibizumab gained 1.6 ETDRS (Early Treatment Diabetic Retinopathy Study) letters (95% CI 0.5 to 2.7, p=0.004), while patients on F/TE aflibercept gained 6.1 letters (95% CI 5.1 to 7.1, p=2.2e-16). Change in vision at 1 year of the F/TE aflibercept group was 4.1 letters higher (95% CI 2.5 to 5.8, p=1.3e-06) compared with the PRN ranibizumab group after adjusting for age, starting VA, gender and year of starting therapy. The F/TE aflibercept group had significantly more injections compared with the PRN ranibizumab group (7.0 vs 5.8, p<2.2e-16), but required less clinic visits than the PRN ranibizumab group (10.8 vs 9.0, p<2.2e-16). Cost-effectiveness analysis showed an incremental cost-effectiveness ratio of 58 047.14 GBP/quality-adjusted life year for continuous aflibercept over PRN ranibizumab. CONCLUSION: Aflibercept achieved greater VA gains at 1 year than ranibizumab. The observed VA differences are small and likely to be related to more frequent treatment with aflibercept, suggesting that ranibizumab should also be delivered by F/TE posology.

The United Kingdom Diabetic Retinopathy Electronic Medical Record Users Group, Report 1: baseline characteristics and visual acuity outcomes in eyes treated with intravitreal injections of ranibizumab for diabetic macular oedema.

AIMS: To describe baseline characteristics and visual outcome for eyes treated with ranibizumab for diabetic macular oedema (DMO) from a multicentre database. METHODS: Structured clinical data were anonymised and extracted from an electronic medical record from 19 participating UK centres: age at first injection, ETDRS visual acuity (VA), number of injections, ETDRS diabetic retinopathy (DR) and maculopathy grade at baseline and visits. The main outcomes were change in mean VA from baseline, number of injections and clinic visits and characteristics affecting VA change and DR grade. RESULTS: Data from 12 989 clinic visits was collated from baseline and follow-up for 3103 eyes. Mean age at first treatment was 66 years. Mean VA (letters) for eyes followed at least 2 years was 51.1 (SD=19.3) at baseline, 54.2 (SD: 18.6) and 52.5 (SD: 19.4) at 1 and 2 years, respectively. Mean visual gain was five letters. The proportion of eyes with VA of 72 letters or better was 25% (baseline) and 33% (1 year) for treatment naïve eyes. Eyes followed for at least 6 months received a mean of 3.3 injections over a mean of 6.9 outpatient visits in 1 year. CONCLUSIONS: In a large cohort of eyes with DMO treated with ranibizumab injections in the UK, 33% of patients achieved better than or equal to 6/12 in the treated eye at 12 months compared with 25% at baseline. The mean visual gain was five letters. Eyes with excellent VA at baseline maintain good vision at 18 months.

Surveillance Potential of Non-Native Hawaiian Birds for Detection of West Nile Virus.

West Nile virus (WNV) was first detected in North America in 1999. Alaska and Hawaii (HI) remain the only U.S. states in which transmission of WNV has not been detected. Dead bird surveillance has played an important role in the detection of the virus geographically, as well as temporally. In North America, corvids have played a major role in WNV surveillance; however, the only corvid in HI is the endangered Hawaiian crow that exists only in captivity, thus precluding the use of this species for WNV surveillance in HI. To evaluate the suitability of alternate avian species for WNV surveillance, we experimentally challenged seven abundant non-native bird species present in HI with WNV and compared mortality, viremia, oral shedding of virus, and seroconversion. For detection of WNV in oral swabs, we compared viral culture, reverse-transcriptase polymerase chain reaction, and the RAMP(®) test. For detection of antibodies to WNV, we compared an indirect and a competitive enzyme-linked immunoassay. We found four species (house sparrow, house finch, Japanese white-eye, and Java sparrow) that may be useful in dead bird surveillance for WNV; while common myna, zebra dove, and spotted dove survived infection and may be useful in serosurveillance.

Wildlife mortality investigation and disease research: contributions of the USGS National Wildlife Health Center to endangered species management and recovery.

The U.S. Geological Survey-National Wildlife Health Center (NWHC) provides diagnostic services, technical assistance, applied research, and training to federal, state, territorial, and local government agencies and Native American tribes on wildlife diseases and wildlife health issues throughout the United States and its territories, commonwealth, and freely associated states. Since 1975, >16,000 carcasses and specimens from vertebrate species listed under the Endangered Species Act have been submitted to NWHC for determination of causes of morbidity or mortality or assessment of health/disease status. Results from diagnostic investigations, analyses of the diagnostic database, technical assistance and consultation, field investigation of epizootics, and wildlife disease research by NWHC wildlife disease specialists have contributed importantly to the management and recovery of listed species.

Visual function following photodynamic therapy for central serous chorioretinopathy: a comparison of automated macular microperimetry versus best-corrected visual acuity.

BACKGROUND: The study compares the change in best-corrected visual acuity with the change in central retinal sensitivity before treatment and 6 months after treatment with photodynamic therapy in patients with symptomatic central serous chorio retinopathy. DESIGN: Prospective, single-centre, interventional case series. PARTICIPANTS: Eleven consecutive patients with previously untreated central serous chorio retinopathy. METHODS: Patients had microperimetry and best-corrected visual acuity recorded before and 6 months after treatment with photodynamic therapy. Refracted best-corrected visual acuity was assessed at 2 m and adjusted to give the number of letters read at 1 m. Threshold microperimetry was performed by presenting a Goldman III stimulus to 29 points over the central 12° around fixation. Significant visual improvement at 6 months was defined as a best-corrected visual acuity ≥10 letters or, microperimetry change in mean retinal sensitivity ≥2 decibels (dB). MAIN OUTCOME MEASURES: Improvement in best-corrected visual acuity compared with microperimetry following photodynamic therapy treatment in patients with central serous chorio retinopathy. RESULTS: All patients reported a subjective improvement in vision and had complete resolution of subretinal fluid at 6 months. Two patients had a significant improvement in best-corrected visual acuity (mean ± SD +4.2 ± 5.8 letters), compared with all 11 patients who recorded a significant improvement in mean retinal sensitivity (mean ± SD 4.6 ± 1.9 dB) (P < 0.001). CONCLUSIONS: These data suggest that compared with microperimetry, best-corrected visual acuity is underestimating the effectiveness of photodynamic therapy in the treatment of central serous chorio retinopathy.

Visual outcome after intravitreal ranibizumab for wet age-related macular degeneration: a comparison between best-corrected visual acuity and microperimetry.

PURPOSE: The purpose of this study was to compare the observed change in best-corrected visual acuity (BCVA) with the change in central retinal sensitivity pretreatment and 1 month after 3 consecutive treatments with ranibizumab in patients with wet age-related macular degeneration. METHODS: Ten consecutive patients with untreated age-related macular degeneration underwent microperimetric and BCVA assessment before and 1 month after 3 consecutive treatments with ranibizumab. Best-corrected visual acuity was assessed at 2 m by using the Early Treatment Diabetic Retinopathy Study chart. Threshold microperimetry was performed using a Goldman III stimulus to 45 points over the central 12 degrees of the macula. Significant visual improvement after treatment was defined as a change in BCVA >/=10 letters or, on microperimetry, a change in mean retinal sensitivity > or = 2 dB. RESULTS: One month after treatment, the median change in BCVA was +6 letters (range, -15 to +12), and the mean change in the mean retinal sensitivity was +2.86 dB (standard deviation, 1.55 dB). One patient recorded a significant improvement in BCVA compared with 8 patients who recorded a significant improvement in mean retinal sensitivity (P = 0.016). CONCLUSION: Compared with microperimetry, BCVA seems to significantly underestimate the change in visual function experienced by patients treated with ranibizumab.

Experimental infection of a North American raptor, American Kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1).

Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV) subtype H5N1. Should HPAIV (H5N1) reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1) infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1). All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1) is introduced into North America.

To investigate the prevalence of polypoidal choroidal vasculopathy in presumed age-related peripapillary subretinal neovascular membranes.

BACKGROUND: To investigate the prevalence and angiographic appearances of polypoidal choroidal vasculopathy (PCV) masquerading as age-related peripapillary subretinal neovascular membranes (PSRNVM). METHODS: A consecutive case series of all patients investigated for presumed age-related PSRNVM in our tertiary referral centre over the period September 2006-2007. The presenting clinical features and fundus fluorescein angiographic (FFA) characteristics of each patient's lesion were identified. Any accompanying Indocyanine Green Angiogram (ICGA) was also reviewed, and on the basis of this investigation patients were classified into one of three groups: proven PCV, probable PCV and PSRNVM. RESULTS: Thirty patients with presumed age-related PSRNVM were identified. The FFA leakage pattern was occult in 21 patients and classic in nine patients. Sixteen patients also had ICGA performed. In 14 of these patients the original FFA leakage pattern was occult, and in two it was classic. Of the 14 patients with occult leakage on FFA who subsequently underwent ICGA all were found to have PCV. CONCLUSIONS: PCV is important and underrecognized in presumed age-related PSRNVMs. In such cases, particularly when the pattern of leakage on the fluorescein angiogram is occult, ICGA should be performed to identify the site of the polyps and if required to direct treatment.

A hybrid cohort individual sampling natural history model of age-related macular degeneration: assessing the cost-effectiveness of screening using probabilistic calibration.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of visual impairment and blindness. It is likely that treatment of AMD at earlier stages is more effective than later treatment; thus, screening for AMD should be considered. The aim of this study was to develop a natural history model of AMD to estimate the cost-effectiveness of screening. METHODS: A hybrid cohort/individual sampling decision analytic model was developed. Primary data sets, expert elicitation, and data from the literature were used to populate the model. To incorporate joint parameter uncertainty, and to populate unobservable parameters, an innovative form of probabilistic calibration was applied to a range of output parameters. RESULTS: In the reference case, annual screening from age 60 y is the most cost-effective option, although this is subject to high levels of uncertainty. Alternative, age-specific utility values show that screening is predicted to be less cost-effective, assuming interventions that reduce progression to wet AMD moderately improve the cost-effectiveness of screening, whereas the addition of anti-vascular endothelial growth factor therapy for juxtafoveal or subfoveal wet AMD lesions improves the cost-effectiveness of screening significantly. CONCLUSIONS: The extent of the uncertainty around the mean results, and the additional resources and possible reorganization of services required to implement screening, indicate that it may be preferable to reduce the level of uncertainty before implementing screening for AMD. Initial actions may be best targeted at assessing how routine data may be used to describe clinical presentation, a screening pilot study, and a secondary costing study.

Differentiation at higher levels of cognitive ability: evidence from the United States.

Most psychologists and educators assume that intelligence is a linear construct, meaning that smart people simply have more intelligence than their less gifted peers. Likewise, individuals with mental retardation are thought to have less intelligence. In contrast to this widely accepted belief, the authors posed an alternative hypothesis--that intelligence is qualitatively different in various populations. Using factor analysis of a standardization sample of the Woodcock-Johnson Test of Cognitive Ability (R. W. Woodcock & M. B. Johnson, 1989), the authors examined the nature of intellect across ability. Results indicated that the amount of variance attributable to Spearman's g declined as measured intellectual ability increased.

The impact of age-related macular degeneration on health status utility values.

PURPOSE: To estimate health status utility values in patients with age-related macular degeneration (ARMD) associated with visual impairments, by using preference-based measures of health. METHOD: This was a cross-sectional study involving patients with unilateral or bilateral ARMD who attended a large teaching hospital. Patients underwent visual tests (near and distant visual acuity [VA] and contrast sensitivity [CS]) and completed health status questionnaires including the Index of Visual Function (VF)-14 and three preference-based measures (the Health Utilities Index Mark III [HUI-3], the EuroQoL Health Questionnaire [EQ-5D], and the Short Form 6D Health Status Questionnaire [SF-6D]) and the time tradeoff (TTO). The mean health status is presented for five groups, defined according to the VA in the better-seeing eye and for four CS groups. RESULTS: Two hundred nine patients were recruited with substantial loss of visual function as obtained by visual tests (mean decimal VA in the better-seeing eye: 0.2) and self-report (mean VF-14 score: 41.5). The mean (+/-SD) utilities were 0.34 +/- 0.28 for HUI-3, 0.66 +/- 0.14 for SF-6D, 0.72 +/- 0.22 for EQ-5D, and 0.64 +/- 0.31 for TTO. The HUI-3 had the highest correlation with VA and CS (0.40 and -0.34), followed by TTO (0.25 and -0.21). Across the VA and CS groups, only HUI3 and TTO had a significant linear trend (P < 0.05). In a regression model with CS and VA as explanatory variables, only the coefficient on CS was statistically significant. CONCLUSIONS: ARMD is associated with a substantial impact on patients' health status, but this was not reflected in two of the generic preference-based measures used. The HUI-3 seems to be the instrument of choice for use in economic evaluations in which community data are needed. It may be more appropriate to base economic models on CS or some combination of CS and VA rather than on VA alone.