A multinational survey of potential participant perspectives on ocular gene therapy

Amidst rapid advancements in ocular gene therapy, understanding patient perspectives is crucial for shaping future treatment choices and research directions. This international cross-sectional survey evaluated knowledge, attitudes, and perceptions of ocular genetic therapies among potential recipients with inherited retinal diseases (IRDs). Survey instruments included the Attitudes to Gene Therapy-Eye (AGT-Eye), EQ-5D-5L, National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25), and Patient Attitudes to Clinical Trials (PACT-22) instruments. This study included 496 participant responses (89% adults with IRDs; 11% parents/guardians/carers) from 35 countries, with most from the United States of America (USA; 69%) and the United Kingdom (11%). Most participants (90%) indicated they would likely accept gene therapy if it was available, despite only 45% agreeing that they had good knowledge of gene therapy. The main sources of information were research registries (60% of participants) and the internet (61%). Compared to data from our recently published Australian national survey of people with IRDs (n = 694), USA respondents had higher knowledge of gene therapy outcomes, and Australian respondents indicated a higher perceived value of gene therapy treatments. Addressing knowledge gaps regarding outcomes and financial implications will be central to ensuring informed consent, promoting shared decision-making, and the eventual clinical adoption of genetic therapies.

The Better Operative Outcomes Software Tool (BOOST) Prospective Study: Improving the Quality of Cataract Surgery Outcomes in Low-Resource Settings

PURPOSE

Post-operative vision impairment is common among patients who have undergone cataract surgery in low-resource settings, impacting quality of clinical outcomes and patient experience. This prospective, multisite, single-armed, pragmatic validation study aimed to assess whether receiving tailored recommendations via the free Better Operative Outcomes Software Tool (BOOST) app improved surgical outcomes, as quantified by post-operative unaided distance visual acuity (UVA) measured 1-3 days after surgery.

METHODS

During the baseline data collection round, surgeons in low and middle-income countries recorded clinical characteristics of 60 consecutive cataract cases in BOOST. Additional data on the causes of poor outcomes from 20 consecutive cases with post-operative UVA of <6/60 (4-12 weeks post-surgery) were entered to automatically generate tailored recommendations for improvement, before 60 additional consecutive cases were recorded during the follow-up study round. Average UVA was compared between cases recorded in the baseline study round and those recorded during follow-up.

RESULTS

Among 4,233 cataract surgeries performed by 41 surgeons in 18 countries, only 2,002 (47.3%) had post-operative UVA 6/12 or better. Among the 14 surgeons (34.1%) who completed both rounds of the study (1,680 cases total), there was no clinically significant improvement in post-operative average UVA (logMAR units ±SD) between baseline (0.50 ± 0.37) and follow-up (0.47 ± 0.36) rounds (mean improvement 0.03, p = 0.486).

CONCLUSIONS

Receiving BOOST-generated recommendations did not result in improved UVA beyond what could be expected from prospective monitoring of surgical outcomes alone. Additional research is required to assess whether targeted support to implement changes could potentiate the uptake of app-generated recommendations and improve outcomes.

Diagnostic accuracy of self-reported age-related macular degeneration in the ASPREE Longitudinal Study of Older Persons

BACKGROUND

The validity of findings from epidemiological studies using self-report of ophthalmic conditions depends on several factors. We assessed the diagnostic accuracy of self-reported age-related macular degeneration (AMD) among older Australians enroled in a primary prevention clinical trial and compared diagnostic accuracy between demographic subgroups.

METHODS

At baseline (2010-2015), Australian sub-study participants of the ASPirin in Reducing Events in the Elderly (ASPREE) trial, underwent bilateral two-field, 45° non-mydriatic colour retinal photography. Beckman classification of any-stage AMD was used as the reference standard diagnosis. Participants were asked whether a doctor had ever diagnosed them with "macular degeneration" (the index test) via a paper-based questionnaire as part of the ASPREE Longitudinal Study of Older Persons (ALSOP) within the first year of enrolment.

RESULTS

In total, 4193 participants were included (aged 70-92 years, 50.8% female). Of those, 262 (6.3%) reported having AMD and 92 (2.2%) were unsure. Retinal grading detected 2592 (61.8%) with no AMD, 867 (20.7%) with early, 686 (16.4%) with intermediate and 48 (1.1%) with late AMD (n = 1601 with any-stage AMD, 38.2%). Self-reported AMD had 11.4% sensitivity (95% CI 9.9-13.1) and 96.9% specificity (95% CI 96.2-97.6) for any-stage AMD, with 69.8% and 63.9% positive and negative predictive values. Sensitivity was higher among participants with late-stage AMD (87.5%), older participants (26.8%), and those with poorer vision (41.0%).

CONCLUSIONS

Although most participants with late-stage AMD were aware of having AMD, the majority with early and intermediate AMD were not. Therefore, findings from studies that rely on disease self-report should be interpreted with caution.

Prospective, Randomized Controlled Trial of Cataract Surgery vs Combined Cataract Surgery With Insertion of iStent Inject

PURPOSE

To evaluate the efficacy and safety of combined cataract surgery with insertion of an ab interno trabecular microbypass device (iStent Inject, Glaukos Corporation) compared to cataract surgery alone in patients with mild-to-moderate glaucoma.

DESIGN

Prospective, randomized, assessor-masked controlled trial at a single centre.

PARTICIPANTS

Eyes with visually-significant cataract and mild-to-moderate glaucoma with preoperative intraocular pressure (IOP) of 12 to 30 mmHg on 0 to 3 ocular hypotensive medications.

METHODS

Participants eyes were randomized (2017-2020) 1:1 to combined cataract surgery with iStent Inject (treatment group, n = 56) or cataract surgery alone (control group, n = 48), and followed up for 2 years.

MAIN OUTCOME MEASURES

The co-primary effectiveness endpoints were the number of ocular hypotensive medications and IOP at 24-months post-surgery. The secondary effectiveness endpoints were ocular comfort as measured by the Ocular Surface Disease Index (OSDI) and vision-related quality of life as measured by the Glaucoma Activity Limitation Questionnaire (GAL-9) at 24-months. Safety measures included postoperative visual acuity, any unplanned return to the operating theatre, adverse events, and complications.

RESULTS

Participants (67.3% male) were aged 53 to 85 years, and treatment groups were similar in terms of mean medicated IOP (treatment group 17.7 mmHg ± 4.0; control group 17.1 mmHg ± 3.1), and number of ocular hypotensive medications (treatment group 1.69 ± 1.05; control group 1.80 ± 1.22) at baseline. At 24 months, the number of ocular hypotensive medications were 0.7 ± 0.9 in the treatment groups compared to 1.5 ± 1.9 in the control group, with an adjusted difference of 0.6 fewer medications per eye in the treatment group (95% CI 0.2-1.1, P = 0.008). In the treatment group, 57% of eyes were on no glaucoma medications compared to 36% in the control group. There was no significant difference in IOP between the 2 groups beyond the 4-weeks. There were no differences in patient-reported outcomes between the 2 groups. The visual outcomes and safety profiles were similar between the 2 groups.

CONCLUSIONS

Combined cataract surgery with iStent Inject achieved a clinically- and statistically-significantly greater reduction in ocular hypotensive medication usage at 24-months compared to cataract surgery alone, with no significant difference in IOP.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

EQ-5D-5L health utility scores in Australian adults with inherited retinal diseases: A cross-sectional survey

PURPOSE

Economic evaluations of interventions for ocular disease require utility scores that accurately represent quality of life in the target population. This study aimed to describe the distribution of EQ-5D-5L utility values among Australian adults with symptomatic inherited retinal diseases (IRDs) and to assess the relationship between these scores and vision-related quality of life.

METHODS

A survey was administered predominantly online in 2021. Participants completed the EQ-5D-5L general health utility instrument, the EQ vertical visual analogue scale (EQ-VAS) and the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25). Self-reported IRD diagnoses were classified as being associated with central or widespread retinal involvement.

RESULTS

Responses from 647 participants aged 18-93 years were included, 50.1% were men and 77.6% had an IRD associated with widespread retinal involvement. The majority reported no problems with self-care and no pain/discomfort but did report anxiety/depression and problems with work, study, housework, or family/leisure activities. Most people with widespread involvement reported problems with mobility. Median EQ-5D-5L utility was 0.88 and 0.91 among people with widespread and central involvement, respectively (age and sex-adjusted p = 0.029); and median EQ-VAS was 75 and 80, respectively (adjusted p = 0.003). A moderate curvilinear correlation was observed between EQ-5D-5L and NEI-VFQ-25 composite score (Spearman's ρ 0.69), but not all people with poor vision-related quality of life had low EQ-5D-5L utility values.

CONCLUSIONS

EQ-5D-5L health utility values are correlated with vision-related quality of life among adults with IRDs. However, the EQ-5D-5L may not be sensitive to the full impact of vision impairment on quality of life.

Clinical practice patterns for assessing children with learning difficulties: survey of eye health care professionals

CLINICAL RELEVANCE

Understanding what aspects of vision or binocular vision may affect learning, and how these are assessed, is important for the eye health care professional assessing children with learning difficulties. It is vital that visual dysfunction is identified or excluded in these patients to ensure targeted and timely intervention.

BACKGROUND

The aim of this study was to investigate similarities and differences between eye care professionals in the knowledge, attitudes and practice patterns, when evaluating children with learning difficulties.

METHODS

This study was a cross-occupational, cross-sectional, predominantly quantitative internet-based survey. Ophthalmologists, optometrists, and orthoptists working in Australia were eligible to participate. A questionnaire comprising of 31 multiple-choice questions with up to 19 additional branching questions was distributed using REDCap in September 2022.

RESULTS

A total of 130 responses were analysed (6 ophthalmologists, 84 orthoptists and 40 optometrists of whom 9 were practicing behavioural vision care). Most respondents assessed distance visual acuity (95%), near stereoacuity (85%), presence of strabismus (88%) and ocular movements (91%). Near vision was assessed less often (65%). Optometrists were most likely to measure colour vision (p < 0.002), accommodation and undertake a subjective refraction (each p < 0.001). Ophthalmologists were least likely to measure convergence (p = 0.041) but more likely to undertake a cycloplegic refraction (p = 0.044). More optometrists practicing behavioural vision care reported testing binocular vision (p = 0.026), fusional vergence (p < 0.001), saccades (p = 0.066), and smooth pursuit (p = 0.050) than other professions. There was a positive correlation between frequency and confidence level when assessing children with learning difficulties (ρ = 0.64). Respondents referred to paediatricians (39%), speech pathologists (30%), educational psychologists (29%) and general practitioners (29%).

CONCLUSION

Despite similarities across occupations, there were differences in testing the vision and binocular functions of children with learning difficulties. Future research should aim to establish minimum standards for assessing this patient cohort to ensure consistent and relevant assessment.

Increased Glaucoma Case-finding Through Routine Optical Coherence Tomography in Optometry Practice

OBJECTIVE

Timely detection of glaucoma is key to preventing or delaying vision loss. This study aimed to assess whether the routine use of optical coherence tomography (OCT) by optometrists for detection of glaucomatous changes in the optic nerve and retina increased glaucoma referrals to ophthalmologists.

DESIGN

This study was a retrospective review of routinely-collected electronic medical records of patients from a chain of 331 optometry practices in Australia.

PARTICIPANTS

Electronic medical records were reviewed for every patient aged 18-99 years who attended an included practice between January 1 and July 31, 2019.

METHODS

Odds of referral for glaucoma assessment were compared between practices performing OCT routinely on all patients (OCT practices, n=175) and without OCT (non-OCT practices, n=20). A subset of referrals were assessed by ophthalmologists to determine the false positive referral rate.

MAIN OUTCOME MEASURES

The primary outcome measure of this study was referral to an ophthalmologist for glaucoma assessment. A secondary outcome was the rate of false positive referrals, analysed in a subset of patients referred for glaucoma assessment.

RESULTS

Records from 994,461 patients (59% female) were included and 10,475 (1.1%) were referred for glaucoma assessment. Most referrals were associated with normal intraocular pressure (non-OCT practices: n=496, 66%; OCT practices: n=6,603, 68%). Referral for glaucoma was higher in OCT practices (n=9,719, 1.1%) compared to non-OCT practices (n=756, 0.8%, age-, gender- and location-adjusted odds ratio 1.39, 95% confidence interval 1.10-1.76). Of 318 referred patients (3%, all from OCT practices) for whom ophthalmologist feedback was available, 68 (21%) were considered not to have glaucoma.

CONCLUSIONS

The routine use of OCT in optometric practice may lead to more timely glaucoma detection and prevention of avoidable vision loss.

Self-rated eyesight among healthy older Australians: Baseline results of the ASPREE Longitudinal Study of Older Persons

BACKGROUND

We aimed to describe the self-reported level of eyesight amongst a cohort of relatively healthy older Australian adults, and to investigate associations between poorer self-rated eyesight and demographic, health, and functional characteristics METHODS: The ASPirin in Reducing Events in the Elderly (ASPREE) Longitudinal Study of Older Persons (ALSOP) study was embedded in a multisite trial which recruited independently living Australians from general practices (2010-2014). Self-rated eyesight was recorded on a paper-based questionnaire as Excellent, Good, Fair, Poor, Very poor, or Completely blind at the baseline study wave RESULTS: Data from 14 592 participants (aged 70-95 years, 54.61% female) were included in this cross-sectional analysis. Eighty percent of participants reported excellent or good eyesight (n = 11 677). People with complete blindness were precluded from enrolling but 299 participants (2.0%) reported poor or very poor eyesight, and 2616 rated their eyesight as fair (17.9%). Lower levels of eyesight were associated with being older, female, fewer years of formal education, a primary language other than English, smoking, and self-reported macular degeneration, glaucoma, retinopathy, cataracts, and hearing problems (each p ≤ 0.021). People with lower levels of eyesight had a higher number of falls, frailty characteristics, and depressive symptoms, and lower mental and physical health functioning scores (each p < 0.001) CONCLUSIONS: Whilst most of these healthy older Australians reported good or excellent eyesight, a notable minority reported poor or very poor eyesight, and this was associated with a range of poorer health measures. These findings support the need for additional resources to prevent vision loss and associated sequelae.

Real-World Investigation of Impact of Retinal Fluid in Treatment Naïve Eyes Treated with Anti-VEGF for Neovascular Age-Related Macular Degeneration

BACKGROUND

Traditionally, visual acuity gain and central retinal thickness have been used to measure outcomes when investigating the efficacy of vascular endothelial growth factor (VEGF) inhibitors for patients with neovascular age-related macular degeneration (nARMD). However, localization of retinal fluid may offer additional prognostic value for treatment. The primary aim of this retrospective clinical audit was to investigate whether the presence and location of subretinal fluid has an effect on the visual outcomes of treatment naïve patients with nARMD treated in the real-world setting with VEGF inhibitors. Secondary aims included investigation of change to visual and anatomical outcomes and investigation of the dosing schedule.

METHODS

Retrospective observational study of patients attending one suburban and one regional ophthalmology clinic requiring treatment with VEGF inhibitors for nARMD using single-user non-identifiable data from the Fight Retinal Blindness! Registry from 2014 to 2020. Visual acuity (VA) and central subfield thickness (CST) were recorded at baseline, 3, 6, 12 and 24 months.

RESULTS

Forty-nine eyes of 42 treatment naïve patients were included for analysis (aged 62-89 years). Almost half (49%) presented with a combination of intra- and subretinal fluid at baseline. Intraretinal fluid was present in 75% of eyes but decreased to 22.7% of eyes by 24 months. VA at baseline was 55 letters, and this improved by 6 letters. The change in VA from baseline to 3, 6 and 12 months was statistically significant (p < .05). The mean change in CST from baseline to 3 months was significant (-76 µm). This change was also observed at the other milestones (p < .001).

CONCLUSIONS

The findings of this study suggest that allowing some subretinal fluid to remain will not affect treatment outcomes.

Is the disease risk and penetrance in Leber hereditary optic neuropathy actually low?

Pedigree analysis showed that a large proportion of Leber hereditary optic neuropathy (LHON) family members who carry a mitochondrial risk variant never lose vision. Mitochondrial haplotype appears to be a major factor influencing the risk of vision loss from LHON. Mitochondrial variants, including m.14484T>C and m.11778G>A, have been added to gene arrays, and thus many patients and research participants are tested for LHON mutations. Analysis of the UK Biobank and Australian cohort studies found more than 1 in 1,000 people in the general population carry either the m.14484T>C or the m.11778G>A LHON variant. None of the subset of carriers examined had visual acuity at 20/200 or worse, suggesting a very low penetrance of LHON. Haplogroup analysis of m.14484T>C carriers showed a high rate of haplogroup U subclades, previously shown to have low penetrance in pedigrees. Penetrance calculations of the general population are lower than pedigree calculations, most likely because of modifier genetic factors. This Matters Arising Response paper addresses the Watson et al. (2022) Matters Arising paper, published concurrently in The American Journal of Human Genetics.

Survey of perspectives of people with inherited retinal diseases on ocular gene therapy in Australia

Many gene therapies are in development for treating people with inherited retinal diseases (IRD). We hypothesized that potential recipients of gene therapy would have knowledge gaps regarding treatment. We aimed to assess knowledge, attitudes, and perceptions of genetic therapies among potential recipients with IRD, using a novel instrument we designed (Attitudes to Gene Therapy-Eye (AGT-Eye)) and their associations with demographic data, self-reported visual status, and tools assessing quality of life and attitudes toward clinical trials using a community-based cross-sectional survey of Australian adults with IRD. AGT-Eye, overall quality of life EQ-5D-5L, National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) and Patient Attitudes to Clinical Trials (PACT-22) instruments were administered. Six hundred and eighty-one people completed the study, 51.7% women of mean age 53.5 years (SD ± 15.8). Most participants (91.6%) indicated they would likely accept gene therapy if it was available to them or family members. However, only 28.3% agreed that they had good knowledge of gene therapy. Most obtained information about gene therapy from the internet (49.3%). Respondents with post-graduate degrees scored highest compared to other educational levels on methods (p < 0.001) and outcomes (p = 0.003) and were more likely to see economic value of treatment (p = 0.043). Knowledge gaps were present regarding methods and outcomes of gene therapy. This survey has shown high level of interest in the IRD community for gene therapies, and highlights areas for improved clinician and patient education.

Interobserver Agreement of Electrode to Retina Distance Measurements in a Second-Generation (44-Channel) Suprachoroidal Retinal Prosthesis

Purpose

The electrode to retina (ER) distance is an important contributory factor to the safety and efficacy of a suprachoroidal retinal prosthesis. Measuring ER distance may be performed by different observers during multisite studies. The aim of this study was to assess the interobserver agreement in measuring ER distance.

Methods

Three independent, trained observers measured ER distance from the center of each suprachoroidal electrode to the inner retinal pigment epithelium in spectral-domain optical coherence tomography (SD-OCT) B-scans. A total of 121 ER distance measurements from 77 B-scans collected over 5 months from one subject implanted with a second-generation 44-channel suprachoroidal retinal prosthesis (NCT03406416) were made by each observer.

Results

ER distance ranged from 208 to 509 µm. Pearson's correlation coefficient (ρ) showed agreement of 0.99 (95% confidence interval [CI] = 0.98–0.99) in measuring ER for each pairwise comparison. The mean difference in ER distance between observers ranged from 2.4 to 6.4 µm with pairwise limits of agreement (95% CI) of ±20 µm (5.5% of mean). Intraclass correlation coefficient (ICC) showed agreement of 0.98 (95% CI = 0.97–0.99) between observers.

Conclusions

There is high agreement in measuring ER distances for suprachoroidal retinal prostheses using our systematic approach between multiple, trained observers, supporting the use of a single observer for each image.

Translational Relevance

High interobserver agreement outcomes indicate that multiple, trained observers can be used to take ER measurements across different images in suprachoroidal retinal prosthesis studies. This improves multisite study efficiency and gives confidence in interpreting results relating to the safety and efficacy of suprachoroidal retinal prostheses.

A Second-Generation (44-Channel) Suprachoroidal Retinal Prosthesis: Long-Term Observation of the Electrode-Tissue Interface

Purpose

To report the long-term observations of the electrode–tissue interface and perceptual stability in humans after chronic stimulation with a 44-channel suprachoroidal retinal implant.

Methods

Four subjects (S1–4) with end-stage retinitis pigmentosa received the implant unilaterally (NCT03406416). Electrode impedances, electrode–retina distance (measured using optical coherence tomography imaging), and perceptual thresholds were monitored up to 181 weeks after implantation as the subjects used the prosthesis in the laboratory and in daily life. Stimulation charge density was limited to 32 µC/cm² per phase.

Results

Electrode impedances were stable longitudinally. The electrode–retina distances increased after surgery and then stabilized, and were well-described by an asymptotic exponential model. The stabilization of electrode–retina distances was variable between subjects, stabilizing after 45 weeks for S1, 63 weeks for S2, and 24 weeks for S3 (linear regression; P_gradient > 0.05). For S4, a statistically significant increase in electrode–retina distance persisted (P < 0.05), but by the study end point the rate of increase was clinically insignificant (exponential model: 0.33 µm/wk). Perceptual electrical thresholds were stable in one subject, decreased over time in two subjects (linear model; P < 0.05), and increased slightly in one subject but remained within the predefined charge limits (P = 0.02).

Conclusions

Chronic stimulation with the suprachoroidal retinal prosthesis over 3 years resulted in stable impedances, small individual changes in perceptual electrical thresholds, and no clinically significant increase in electrode–retina distances after a period of settling after surgery.

Translational Relevance

Chronic stimulation with the 44-channel suprachoroidal retinal implant with a charge density of up to 32 µC/cm² per phase is suitable for long-term use in humans.

Interventions for the management of computer vision syndrome: a systematic review and meta-analysis

TOPIC

To evaluate the efficacy and safety of interventions for treating eye strain related to computer use relative to placebo or no treatment.

CLINICAL RELEVANCE

Computer use is pervasive and often associated with eye strain, referred to as "computer vision syndrome" (CVS). Currently, there are no clinical guidelines to help practitioners provide evidence-based advice about CVS treatments, many of which are directly marketed to patients. This systematic review and meta-analysis will help inform best practice for eye care providers.

METHODS

Eligible randomized controlled trials (RCTs) were identified in Ovid MEDLINE, EMBASE, CENTRAL, and trial registries, searched from inception to November 23, 2021. Eligible studies were appraised for risk of bias, and synthesized. The certainty of the body of evidence was judged using GRADE. Standardized mean differences (SMD) were used when differently scaled measures were combined.

RESULTS

Forty-five RCTs, involving 4497 participants, were included. Multifocal lenses did not improve visual fatigue scores compared to single-vision lenses (three RCTs, SMD: 0.11; 95% confidence interval (CI) -0.14 to 0.37; p=0.38). Visual fatigue symptoms were not reduced by blue-blocking spectacles (three RCTs), with evidence judged to be of low certainty. Relative to placebo, oral berry extract supplementation for 4 to 12 weeks did not improve visual fatigue (seven RCTs, SMD: -0.27; 95%CI -0.70 to 0.16; p=0.22), and dry eye symptoms (four RCTs, SMD: -0.10; 95%CI -0.54 to 0.33; p=0.65). Likewise, berry extract supplementation had no effect on critical flicker-fusion frequency (CFF) or accommodative amplitude. Oral omega-3 fatty acid supplementation for 45 days to 3 months improved dry eye symptoms (two RCTs, mean difference, MD: -3.36 units out of 18; 95%CI -3.63 to -3.10; p<0.00001) relative to placebo. Oral carotenoid supplementation improved CFF (two RCTs, MD: 1.55 Hz; 95%CI 0.42 to 2.67; p=0.007) relative to placebo, although the clinical significance of this finding is unclear.

CONCLUSIONS

We found no high certainty evidence supporting the use of any of the therapies analyzed. There was low certainty evidence that oral omega-3 supplementation reduces dry eye symptoms in symptomatic computer users.

Clinical Practice Guidelines for the Detection and Treatment of Amblyopia: A Systematic Literature Review

PURPOSE

The World Health Organization's Package of Eye Care Interventions (PECI) aims to support incorporation of amblyopia detection and treatment into health service provision. The aim of this study was to systematically review clinical practice guidelines (CPGs) for amblyopia to inform the development of this package.

METHODS

MEDLINE, Embase, CINAHL and Global Index Medicus databases, guideline databases and professional body websites were searched for CPGs published in English between 2010 and 9th March 2020. Guidelines were assessed using the AGREE II tool.

RESULTS

Five CPGs from North America published between 2017-2019 were identified. One CPG provided recommendations on amblyopia treatment and four focused on amblyopia detection and assessment. Non-specialist screening for amblyopic risk factors was recommended in children aged 3-5 years. At least one comprehensive eye examination was recommended for infants and children aged 0-5 years. Treatment recommendations consisted of refractive correction followed by occlusion or cycloplegic penalization.

CONCLUSIONS

Additional evidence is required to compare the benefits and limitations of comprehensive eye examinations for asymptomatic children to those from screening programs. Identified CPGs were produced in high-resource countries and may not be readily applied in lower resource settings where the PECI has the greatest potential to improve service provision.

Intereye Symmetry in Bietti Crystalline Dystrophy

PURPOSE

To evaluate anatomic and functional intereye symmetry among individuals with Bietti crystalline dystrophy (BCD) using clinical and multimodal imaging methods, with a focus on the number, area, and distribution of the characteristic retinal crystalline deposits.

DESIGN

Observational case series with prospective and retrospective data.

METHODS

Setting: Multicenter.

STUDY POPULATION

Thirteen Australian and New Zealand participants (26 eyes) with confirmed biallelic CYP4V2 mutations and a characteristic BCD fundus appearance. Procedures and main outcome measures: Crystals visible on color fundus photography were manually counted. Crystals were superimposed on aligned multimodal fundus images. Spearman's correlation coefficients (ρ), intraclass correlation coefficients (ICCs), and Bland-Altman plots were used to quantify symmetry between eyes.

MAIN OUTCOME MEASURES

Fundus crystal area and count, and absent-autofluorescence (absent-AF) area.

RESULTS

Median participant age was 48 years (interquartile range: 40-60 years). Intereye symmetry was high for fundus crystal area (ρ = 1.00, 95% confidence interval [CI]: 1.00-1.00; ICC = 0.97, 95% CI: 0.88-0.99), fundus crystal count (ρ = 0.98, 95% CI: 0.92-1.00; ICC = 0.97, 95% CI: 0.89-0.99), and absent-AF area (ρ = 0.88, 95% CI: 0.53-0.98; ICC = 0.98, 95% CI: 0.90-0.99). Average foveal volume, foveal crystal count and area, average and central foveal thickness, best corrected visual acuity, and average macular and central foveal sensitivity were not highly correlated between eyes.

CONCLUSIONS

This study demonstrated strong intereye symmetry measured by fundus crystal area, fundus crystal number, and absent-AF area. This may influence the choice of outcome measures for future therapeutic trials for BCD and provides valuable clinical information for ophthalmologists involved in the care and counseling of patients with BCD.

The MOLES system to guide the management of melanocytic choroidal tumours: can optometrists apply it?

CLINICAL RELEVANCE

Although melanocytic choroidal tumours of the choroid are a common eye pathology, no standardised protocol exists for their management in the community.

BACKGROUND

Choroidal naevi are found in approximately 6% of the adult White population, whereas choroidal melanomas are rare, with an annual incidence of 5-10/million/year. Multimodal imaging has advanced the understanding of malignancy imaging biomarkers, but distinguishing between a small melanoma and naevus remains difficult and an algorithm for their management by community practitioners has not been uniformly adopted. One of the authors (BD) devised the MOLES scoring system, which indicates malignancy likelihood according to mushroom shape, orange pigment, large size, enlargement, and subretinal fluid. When applied by ocular oncologists, the system accurately distinguishes choroidal naevi from melanomas. The aim of this study was to evaluate whether community optometrists can appropriately manage patients with melanocytic choroidal tumours using this system.

METHODS

Clinical images of 25 melanocytic choroidal tumours were presented in an online survey, including colour fundus photographs, fundus autofluorescence, optical coherence tomography, and B-scan ultrasound images. Using the MOLES system, 39 optometrists diagnosed tumours as naevus or probable melanoma and decided between community monitoring and ophthalmologist referral. Responses were compared to MOLES grading of the same clinical images by ocular oncologists.

RESULTS

Using MOLES, optometrists correctly identified 389/406 probable melanomas (95.8% sensitivity) and 331/516 choroidal naevi (64.1% specificity); correctly referred 773/778 tumours to an ophthalmologist (99.4% sensitivity); and correctly managed 80/144 lesions (55.6% specificity) in the community.

CONCLUSION

Optometrists safely applied the MOLES scoring system in this survey. Further measures are indicated to reduce choroidal naevi over-referral and evaluate MOLES system usage in clinical optometric practice, where some imaging modalities may not be readily available.

Measurement Properties of the Attitudes to Gene Therapy for the Eye (AGT-Eye) Instrument for People With Inherited Retinal Diseases

Purpose

To assess the measurement properties of the Attitudes to Gene Therapy for the Eye (AGT-Eye) instrument among Australian adults with inherited retinal diseases (IRDs) and parents/caregivers of people with IRDs. Constructs of interest included sources of information, knowledge of treatment methods, awareness of treatment outcomes, and perceived value of gene therapy for IRDs.

Methods

A cross-sectional, self-reported, 30-item questionnaire was administered in English from January to June 2021. It was predominantly conducted online with phone and paper alternatives available. Rating scale models were generated separately for each of the four subscales to assess fit, discrimination, and differential item functioning of the items, as well as targeting, reliability, and precision of the subscales. Principal components analysis was used to assess dimensionality.

Results

Responses from 681 participants (87.1% online, 12.9% phone/mail) were included (ages 18-93 years; 51.7% female). Removal of two poorly performing items slightly improved subscale properties. Item reliability was high for each of the subscales; however, person reliability was suboptimal, with limited ability to stratify participants according to traits (person separation coefficient < 1.8 for each subscale). There was no evidence of differential item functioning by gender, online completion, or patient/caregiver status. Evidence of multidimensionality was detected for two subscales.

Conclusions

Four subscales of the AGT-Eye will be used to analyze operational knowledge and perceived value of ocular gene therapy in Australia. Measurement properties may be improved with the generation of additional items.

Translational Relevance

Physicians can use the AGT-Eye to assess knowledge and expectations of potential recipients of ocular gene therapy for IRDs.

Topical application of TAK1 inhibitor encapsulated by gelatin particle alleviates corneal neovascularization

Rationale: Corneal neovascularization (CoNV) is a severe complication of various types of corneal diseases, that leads to permanent visual impairment. Current treatments for CoNV, such as steroids or anti-vascular endothelial growth factor agents, are argued over their therapeutic efficacy and adverse effects. Here, we demonstrate that transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) plays an important role in the pathogenesis of CoNV. Methods: Angiogenic activities were assessed in ex vivo and in vitro models subjected to TAK1 inhibition by 5Z-7-oxozeaenol, a selective inhibitor of TAK1. RNA-Seq was used to examine pathways that could be potentially affected by TAK1 inhibition. A gelatin-nanoparticles-encapsulated 5Z-7-oxozeaenol was developed as the eyedrop to treat CoNV in a rodent model. Results: We showed that 5Z-7-oxozeaenol reduced angiogenic processes through impeding cell proliferation. Transcriptome analysis suggested 5Z-7-oxozeaenol principally suppresses cell cycle and DNA replication, thereby restraining cell proliferation. In addition, inhibition of TAK1 by 5Z-7-oxozeaenol blocked TNFα-mediated NFκB signalling, and its downstream genes related to angiogenesis and inflammation. 5Z-7-oxozeaenol also ameliorated pro-angiogenic activity, including endothelial migration and tube formation. Furthermore, topical administration of the gelatin-nanoparticles-encapsulated 5Z-7-oxozeaenol led to significantly greater suppression of CoNV in a mouse model compared to the free form of 5Z-7-oxozeaenol, likely due to extended retention of 5Z-7-oxozeaenol in the cornea. Conclusion: Our study shows the potential of TAK1 as a therapeutic target for pathological angiogenesis, and the gelatin nanoparticle coupled with 5Z-7-oxozeaenol as a promising new eyedrop administration model in treatment of CoNV.

Diagnostic accuracy of Immulite® TSI immunoassay for thyroid-associated orbitopathy in patients with recently diagnosed Graves' hyperthyroidism

PURPOSE

The Immulite® thyroid stimulating immunoglobulin (TSI) immunoassay is a relatively new commercial assay that has shown good diagnostic accuracy in Graves' hyperthyroidism (GH). However, its clinical utility in thyroid-associated orbitopathy (TAO) is less clear. The purpose of this study was to assess the diagnostic accuracy of the Immulite® TSI immunoassay for TAO and investigate the associations between TSI and other clinical measures.

METHODS

One hundred and forty patients that had been diagnosed with GH within the previous 12 months were recruited. Identification and grading of TAO were performed at enrolment and serum samples were analysed using the Immulite® TSI immunoassay.

RESULTS

Of the 140 participants recruited, 75 (53.6%) had TAO. Age, sex and time since GH diagnosis were similar between those with and without TAO (p ≥ 0.300). TSI level tended to decrease with increasing time from GH diagnosis (Spearman's ρ - 0.28, 95% CI - 0.43, - 0.12). TSI levels were higher among those with than those without TAO (median 4.0 vs. 2.7 IU/L, respectively, p = 0.037). There was no correlation between TSI level and inflammatory index score (ρ = 0.14, 95% CI - 0.03, 0.30) or clinical severity (p = 0.527) among those with TAO. TSI level showed poor diagnostic accuracy for TAO (area under the receiver operating characteristic curve 0.60, 95% CI 0.51, 0.70).

CONCLUSIONS

Although Immulite® TSI level was higher in the presence of TAO, it showed poor diagnostic accuracy and no correlation with clinical markers of TAO severity or activity.

Functional Vision in the Real-World Environment With a Second-Generation (44-Channel) Suprachoroidal Retinal Prosthesis

Purpose

In a clinical trial (NCT03406416) of a second-generation (44-channel) suprachoroidal retinal prosthesis implanted in subjects with late-stage retinitis pigmentosa (RP), we assessed performance in real-world functional visual tasks and emotional well-being.

Methods

The Functional Low-Vision Observer Rated Assessment (FLORA) and Impact of Vision Impairment-Very Low Vision (IVI-VLV) instruments were administered to four subjects before implantation and after device fitting. The FLORA contains 13 self-reported and 35 observer-reported items ranked for ease of conducting task (impossible-easy, central tendency given as mode). The IVI-VLV instrument quantified the impact of low vision on daily activities and emotional well-being.

Results

Three subjects completed the FLORA for two years after device fitting; the fourth subject ceased participation in the FLORA after fitting for reasons unrelated to the device. For all subjects at each post-fitting visit, the mode ease of task with device ON was better or equal to device OFF. Ease of task improved over the first six months with device ON, then remained stable. Subjects reported improvements in mobility, functional vision, and quality of life with device ON. The IVI-VLV suggested self-assessed vision-related quality of life was not impacted by device implantation or usage.

Conclusions

Subjects demonstrated sustained improved ease of task scores with device ON compared to OFF, indicating the device has a positive impact in the real-world setting.

Translational Relevance

Our suprachoroidal retinal prosthesis shows potential utility in everyday life, by enabling an increased environmental awareness and improving access to sensory information for people with end-stage RP.

Focus on Survival Analysis for Eye Research

Analysis of time-to-event data, otherwise known as survival analysis, is a common investigative tool in ophthalmic research. For example, time-to-event data is useful when researchers are interested in investigating how long it takes for an ocular condition to worsen or whether treatment can delay the development of a potentially vision-threatening complication. Its implementation requires a different set of statistical tools compared to those required for analyses of other continuous and categorial outcomes. In this installment of the Focus on Data series, we present an overview of selected concepts relating to analysis of time-to-event data in eye research. We introduce censoring, model selection, consideration of model assumptions, and best practice for reporting. We also consider challenges that commonly arise when analyzing time-to-event data in ophthalmic research, including collection of data from two eyes per person and the presence of multiple outcomes of interest. The concepts are illustrated using data from the Laser Intervention in Early Stages of Age-Related Macular Degeneration study and statistical computing code for Stata is provided to demonstrate the application of the statistical methods to illustrative data.

A scoping review of studies using observational data to optimise dynamic treatment regimens

BACKGROUND

Dynamic treatment regimens (DTRs) formalise the multi-stage and dynamic decision problems that clinicians often face when treating chronic or progressive medical conditions. Compared to randomised controlled trials, using observational data to optimise DTRs may allow a wider range of treatments to be evaluated at a lower cost. This review aimed to provide an overview of how DTRs are optimised with observational data in practice.

METHODS

Using the PubMed database, a scoping review of studies in which DTRs were optimised using observational data was performed in October 2020. Data extracted from eligible articles included target medical condition, source and type of data, statistical methods, and translational relevance of the included studies.

RESULTS

From 209 PubMed abstracts, 37 full-text articles were identified, and a further 26 were screened from the reference lists, totalling 63 articles for inclusion in a narrative data synthesis. Observational DTR models are a recent development and their application has been concentrated in a few medical areas, primarily HIV/AIDS (27, 43%), followed by cancer (8, 13%), and diabetes (6, 10%). There was substantial variation in the scope, intent, complexity, and quality between the included studies. Statistical methods that were used included inverse-probability weighting (26, 41%), the parametric G-formula (16, 25%), Q-learning (10, 16%), G-estimation (4, 6%), targeted maximum likelihood/minimum loss-based estimation (4, 6%), regret regression (3, 5%), and other less common approaches (10, 16%). Notably, studies that were primarily intended to address real-world clinical questions (18, 29%) tended to use inverse-probability weighting and the parametric G-formula, relatively well-established methods, along with a large amount of data. Studies focused on methodological developments (45, 71%) tended to be more complicated and included a demonstrative real-world application only.

CONCLUSIONS

As chronic and progressive conditions become more common, the need will grow for personalised treatments and methods to estimate the effects of DTRs. Observational DTR studies will be necessary, but so far their use to inform clinical practice has been limited. Focusing on simple DTRs, collecting large and rich clinical datasets, and fostering tight partnerships between content experts and data analysts may result in more clinically relevant observational DTR studies.

Prevalence and associations of non-retinopathy ocular conditions among older Australians with self-reported diabetes: The National Eye Health Survey

AIM

To determine the prevalence and associations of non-retinopathy ocular conditions among older Australian adults with diabetes.

METHODS

Multistage random-cluster sampling was used to select 3098 non-indigenous Australians aged 50y or older (46.4% male) and 1738 indigenous Australians aged 40y or older (41.1% male) from all levels of geographic remoteness in Australia. Participants underwent a standardised questionnaire to ascertain diabetes history, and a clinical examination to identify eye disease. We determined the prevalence of uncorrected refractive error, visually significant cataract, cataract surgery, age-related macular degeneration, glaucoma, ocular hypertension, retinal vein occlusion and epiretinal membrane among those with and without self-reported diabetes.

RESULTS

Participants with self-reported diabetes had a higher prevalence of cataract surgery than those without diabetes (28.8% vs 16.9%, OR 1.78, 95%CI: 1.35-2.34 among non-indigenous Australians, and 11.3% vs 5.2%, OR 1.62, 95%CI: 1.22-2.14 among indigenous Australians). Diabetic retinopathy (DR) increased the odds of cataract surgery among self-reported diabetic indigenous and non-indigenous Australians (OR 1.89, P=0.004 and OR 2.33, P<0.001 respectively). Having diabetes for ≥20y and having vision-threatening DR increased the odds of cataract surgery among indigenous Australians with diabetes (OR 3.73, P=0.001 and 7.58, P<0.001, respectively).

CONCLUSION

Most non-retinopathy ocular conditions are not associated with self-reported diabetes. However, to account for Australia's worsening diabetes epidemic, interventions to reduce the impact of diabetes-related blindness should include increased cataract surgery services.

Relationship Between Rod-Mediated Sensitivity, Low-Luminance Visual Acuity, and Night Vision Questionnaire in Age-Related Macular Degeneration

Purpose

To quantify the association between dark adaptation parameters and other clinical measures of visual function among people with and without early and intermediate age-related macular degeneration (AMD).

Methods

In this cross-sectional study, participants underwent multimodal imaging and visual function testing, including best-corrected visual acuity (BCVA), low-luminance visual acuity (LLVA), low-luminance deficit (LLD = BCVA – LLVA) and the 10-item Night Vision Questionnaire (NVQ-10). Dynamic and static dark-adapted chromatic perimetry (DACP) was performed. Sensitivity difference was defined as the difference in sensitivity between the 505-nm and 625-nm stimuli. Rod intercept time (RIT) was estimated as the time required to reach a threshold of −3 log candelas/meter² with the 505-nm stimulus following bleaching. The magnitude of association between the DACP parameters and other clinical tests was estimated via mixed-effects regression.

Results

A total of 51 participants (aged 51–88 years, 65% female, 39% with AMD) were included. RIT was found to be negatively associated with BCVA (P < 0.001), LLVA (P = 0.005), and NVQ-10 score (P = 0.028) but not LLD (P = 0.763). There was no evidence of an association between sensitivity difference and any of the clinical measures (P ≥ 0.081).

Conclusions

Reduced rod function, as determined by RIT, was associated with lower NVQ-10 scores (designed to interrogate rod-mediated function) and with worse BCVA and LLVA (measures of cone function).

Translational Relevance

Decreasing rod function maybe indicative of more generalized photoreceptor dysfunction involving cones. Further development of questionnaires to target function in scotopic conditions may provide an easier to administer test without the need to perform perimetric tests of rod function.

Gram-negative endophthalmitis: A prospective study examining the microbiology, clinical associations and visual outcomes following infection

IMPORTANCE

This is the largest Gram-negative endophthalmitis specific series and provides important evidence to guide management.

BACKGROUND

Endophthalmitis is a sight-threatening emergency. Gram-negative infections are associated with poorer visual outcomes; however, there is limited literature pertaining to this uncommon condition.

DESIGN

Prospective case series.

PARTICIPANTS

All patients presenting with endophthalmitis to a tertiary institution over a 20-year period.

METHODS

Data were collected prospectively and entered into a registry. Patients with microbiological evidence of Gram-negative infection were included in the analysis.

MAIN OUTCOMES MEASURES

Final visual acuity (VA), precipitating events, causative organisms, antibiotic sensitivity profiles and risk factors for poor visual outcomes were reported.

RESULTS

One hundred Gram-negative organisms were isolated in 97 eyes. Final VA was worse than 6/60 in 65 (67.0%) eyes at follow-up and 29 (29.9%) eyes were eviscerated or enucleated. Microbial keratitis (26.8%, n = 26) and Pseudomonas aeruginosa (34.0%, n = 34) were the most common precipitating event and causative organism, respectively. Eight (8.0%) isolates were third-generation cephalosporin resistant; of which, 7 (88.0%) were sensitive to ciprofloxacin. Preceding microbial keratitis (OR = 13.16, P = .015) or P. aeruginosa infections (OR = 3.40, P = .045) were strongly associated with poorer visual outcomes (worse than 6/60).

CONCLUSIONS AND RELEVANCE

Visual outcomes following Gram-negative endophthalmitis are extremely poor, with almost 30% of patients being eviscerated or enucleated. A majority of ceftazidime resistant organisms are sensitive to ciprofloxacin, providing evidence to support the empirical use of quinolones. Clinicians should be mindful that infections secondary to P. aeruginosa or microbial keratitis carry a particularly poor prognosis.

Association between Patient-Reported Outcomes and Time to Late Age-Related Macular Degeneration in the Laser Intervention in Early Stages of Age-Related Macular Degeneration Study

PURPOSE

To investigate the relationship between patient-reported outcome (PRO) questionnaire responses and time to late age-related macular degeneration (AMD; neovascular AMD [nAMD] or multimodal imaging [MMI]-defined atrophy) among individuals with bilateral large drusen, and the prognostic value of baseline PROs for 36-month AMD status.

DESIGN

Exploratory analyses from a multicenter randomized controlled trial of an AMD intervention (Australian New Zealand Clinical Trials Registry identifier, ACTRN12612000704897).

PARTICIPANTS

Sham treatment group of the Laser Intervention in Early Stages of Age-Related Macular Degeneration (LEAD) Study (n = 141; age, 50-88 years; 77% female).

METHODS

The 28-item Impact of Vision Impairment (IVI-28) and 10-item Night Vision Questionnaire (NVQ-10) were administered at the baseline visit. The PRO scores were derived using rating scale models. Multivariate Cox regression adjusting for demographics and clinical measures of vision (low-luminance visual acuity, low-luminance deficit, and microperimetric sensitivity) from the poorer-performing eye was used to investigate the association between PRO scores and time to late AMD in either eye. Multivariate competing-risk regression was used to estimate cause-specific subhazard ratios for nAMD and atrophy in either eye. Cross-validated logistic lasso models were used to estimate the predicted probability of AMD at 36 months. The area under the receiver operating characteristic curve was assessed to compare prognostic accuracy between models with and without PROs.

MAIN OUTCOME MEASURE

Time until nAMD or atrophy in either eye.

RESULTS

The PRO scores were skewed toward higher functional vision. Higher IVI-28 scores were associated with a lower risk of progression to MMI-defined atrophy (20 events: adjusted hazard ratio, 0.65/logit increase; P = 0.002) but not nAMD (10 events; P = 0.562). Insufficient evidence was found of an association between NVQ-10 score and rate of progression to late AMD (P ≥0.149). Baseline IVI-28 scores were found to contribute to the prognosis of atrophy at the 36-month visit (P = 0.010).

CONCLUSIONS

On average, PROs were associated with an increased risk of progression from intermediate AMD to MMI-defined atrophy. Continuing development of instruments to record PROs in the early stages of AMD have the potential to produce inexpensive and efficient tools to assist in the assessment of disease severity and risk of AMD progression.

Correction to: A comparison of methods to estimate the survivor average causal effect in the presence of missing data: a simulation study

In the original publication of this article [1], the incorrect causal diagram was submitted as Fig. 1.

Quantitative Fundus Autofluorescence and Genetic Associations in Macular, Cone, and Cone-Rod Dystrophies

PURPOSE

To investigate quantitatively lipofuscin-associated fundus autofluorescence in patients with macular and cone/cone-rod dystrophies (MD/CCRDs).

DESIGN

Prospective, single-center, case-control study.

PARTICIPANTS

Two hundred thirty patients with MD/CCRDs who had undergone genetic testing and 110 control participants without any eye disease.

METHODS

Participants were examined using quantitative fundus autofluorescence (qAF) imaging with a modified confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference (modified Spectralis HRA-OCT; Heidelberg Engineering, Heidelberg, Germany). Mean qAF values were obtained by averaging measurements from an 8-segment ring centered on the fovea (qAF₈) and compared with controls.

MAIN OUTCOME MEASURES

The qAF₈ levels.

RESULTS

Elevated qAF₈ values were a frequent finding (n = 105 [45%]) and associated with ABCA4 (n = 73 [70%]), PRPH2 (n = 9 [9%]), CERKL (n = 3 [3%]), PROM1 (n = 2 [2%]), CRX (n = 1 [1%]), and CDHR1 (n = 1 [1%]) mutations. Reduced qAF₈ values were rare (n = 15 [7%]) and found predominantly among patients with MERTK (n = 3 [20%]) and RDH5 (n = 2 [13%]) mutations. Patients with normal qAF₈ values (n = 110 [48%]) showed high genotypic heterogeneity. For various genes including ABCA4, PRPH2, CDHR1, and PROM1, higher qAF₈ measures were associated with specific phenotypes and genotypes. For instance, qAF₈ values were normal in PRPH2-related central areolar chorioretinal dystrophy but increased in PRPH2-related Stargardt-like retinopathy. Accordingly, high qAF₈ levels were associated with specific genetic causes and mutation detection rates in characteristic but genetically heterogenous clinical phenotypes, such as a Stargardt-like flecked fundus, bull's eye maculopathy, or pattern dystrophy. In genetically unsolved cases (16 with elevated, 35 with normal, 7 with reduced qAF values), qAF₈ was used to support or reject ambiguous results of genetic testing, to suggest underlying pathogenic pathways, and to predict disease in otherwise healthy participants.

CONCLUSIONS

Quantitative fundus autofluorescence imaging revealed characteristic qAF levels in association with certain gene mutations and in participants without detected mutations. These findings indicate that qAF may facilitate differential diagnostics of MD/CCRDs and may offer novel pathogenetic insights that may be of particular value for the assessment of future treatment approaches.

Comparative Evaluation Of Clinical Characteristics And Visual Outcomes Of Traumatic And Non-Traumatic Graft Dehiscence Following Corneal Transplantation Surgery

Purpose

To compare patient demographics, clinical associations and visual outcomes between traumatic and non-traumatic wound dehiscence, following corneal transplantation.

Methods

Retrospective review of all patients presenting with post-keratoplasty wound dehiscence to the Royal Victorian Eye and Ear Hospital between January 2005 and December 2017. Patients with wound dehiscence following keratoplasty of any cause were included.

Results

Of 71 eyes from 71 patients included, 60 (85%) were penetrating keratoplasty patients. The mean age was 56.4 years (SD=22.7, range 17.6-97) and 62% (n = 44) of patients were male. There were 28 (39%) cases of traumatic dehiscence and 43 (61%) cases of non-traumatic dehiscence. The median time interval from keratoplasty to dehiscence was significantly less in non-traumatic patients than traumatic patients (0.2 years, IQR 0.1-2.0 vs 2.3 years, IQR 0.3-14.8, p=0.01). There was no significant difference in best-corrected visual acuity at 6 months between traumatic and non-traumatic dehiscence (6/60 vs 6/36, p=0.62), suture technique (continuous vs interrupted, p=0.12), or graft type (penetrating keratoplasty vs deep anterior lamellar keratoplasty) after adjusting for keratoconus (p=0.41).

Conclusion

Post-keratoplasty wound dehiscence is a serious complication and can cause significant loss of vision. While the risk of dehiscence is lifelong, the first 3 years post-keratoplasty carry the highest risk, with non-traumatic dehiscence tending to occur earlier than traumatic dehiscence.

A comparison of methods to estimate the survivor average causal effect in the presence of missing data: a simulation study

BACKGROUND

Attrition due to death and non-attendance are common sources of bias in studies of age-related diseases. A simulation study is presented to compare two methods for estimating the survivor average causal effect (SACE) of a binary exposure (sex-specific dietary iron intake) on a binary outcome (age-related macular degeneration, AMD) in this setting.

METHODS

A dataset of 10,000 participants was simulated 1200 times under each scenario with outcome data missing dependent on measured and unmeasured covariates and survival. Scenarios differed by the magnitude and direction of effect of an unmeasured confounder on both survival and the outcome, and whether participants who died following a protective exposure would also die if they had not received the exposure (validity of the monotonicity assumption). The performance of a marginal structural model (MSM, weighting for exposure, survival and missing data) was compared to a sensitivity approach for estimating the SACE. As an illustrative example, the SACE of iron intake on AMD was estimated using data from 39,918 participants of the Melbourne Collaborative Cohort Study.

RESULTS

The MSM approach tended to underestimate the true magnitude of effect when the unmeasured confounder had opposing directions of effect on survival and the outcome. Overestimation was observed when the unmeasured confounder had the same direction of effect on survival and the outcome. Violation of the monotonicity assumption did not increase bias. The estimates were similar between the MSM approach and the sensitivity approach assessed at the sensitivity parameter of 1 (assuming no survival bias). In the illustrative example, high iron intake was found to be protective of AMD (adjusted OR 0.57, 95% CI 0.40-0.82) using complete case analysis via traditional logistic regression. The adjusted SACE odds ratio did not differ substantially from the complete case estimate, ranging from 0.54 to 0.58 for each of the SACE methods.

CONCLUSIONS

On average, MSMs with weighting for exposure, missing data and survival produced biased estimates of the SACE in the presence of an unmeasured survival-outcome confounder. The direction and magnitude of effect of unmeasured survival-outcome confounders should be considered when assessing exposure-outcome associations in the presence of attrition due to death.

Presymptomatic Retinal Sensitivity Changes in Intermediate Age-Related Macular Degeneration Associated With New Retinal Fluid

Purpose

To determine whether change in retinal sensitivity in areas with subretinal or intraretinal fluid secondary to age-related macular degeneration (AMD) precedes visual symptoms. If confirmed, retinal sensitivity testing could be used for home monitoring in AMD.

Methods

Individuals with intermediate AMD enrolled in a longitudinal study were seen every 6 months and underwent best-corrected visual acuity testing (BCVA), spectral domain–optical coherence tomography (SD-OCT), and microperimetry. Asymptomatic individuals who developed incidental, reading center–determined retinal fluid detected on SD-OCT were identified. The point-wise sensitivity (PWS) at the time of fluid detection was compared with 6 and 12 months prior.

Results

Fourteen of 161 individuals developed fluid without symptoms. PWS over fluid areas at detection was reduced compared with 6 (difference −2.04 dB, P < 0.001) and 12 months (−2.27 dB, P < 0.001) prior. PWS over fluid areas was reduced compared with perifluid areas (difference −1.02 dB, P = 0.03), peripheral areas (−1.51 dB, P < 0.001), nonprogressed fellow eyes (−1.49 dB, P = 0.006), and nonprogressed age-matched intermediate AMD eyes (−2.29 dB, P = 0.001). No difference in BCVA was observed in eyes developing fluid compared to eyes that do not develop fluid (P = 0.76).

Conclusions

Retinal areas with fluid on SD-OCT had a corresponding reduction in retinal sensitivity at the time of fluid detection compared with 6 and 12 months prior, in asymptomatic intermediate AMD without change in BCVA.

Translational Relevance

Development of self-monitoring tools to detect changes in retinal sensitivity may be helpful for early detection of retinal fluid suggestive of progression to neovascular AMD before acuity is affected.

Prevalence, associations and characteristics of severe uncorrected refractive error in the Australian National Eye Health Survey

IMPORTANCE

In Australia, nationally representative data of the burden and associations of severe uncorrected refractive error are scarce.

BACKGROUND

To report the prevalence and characteristics of severe uncorrected refractive error in Indigenous and non-Indigenous Australians.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

A total of 3098 non-Indigenous Australians aged 50 to 98 and 1738 Indigenous Australians aged 40 to 92 living in 30 randomly selected Australian sites were examined.

METHODS

Severe uncorrected refractive error was defined as an improvement of ≥2 lines on the logMAR chart in one or both eyes in participants with a presenting visual acuity <6/12.

MAIN OUTCOME MEASURE

Severe uncorrected refractive error RESULTS: Prevalence of severe uncorrected refractive error was 11.0% (95% confidence interval 9.3-13.0) in non-Indigenous and 14.5% (12.5-16.7) in Indigenous Australians. Eighty-two percent of non-Indigenous and 77% of Indigenous participants had a spherical equivalent refraction between -2.00D and +2.00D. Indigenous Australians who were older (odds ratio [OR] for 70-79 years vs 40-49 years = 3.59), resided in outer regional areas (OR = 1.78) and did not have an eye examination in the previous 2-years (OR = 1.50) were associated with higher odds of severe uncorrected refractive error. Geographical remoteness (OR = .68 for inner regional), male gender (OR = 1.30), older age (OR for 70-79 years vs 50-59 years = 1.51) and failure to have an eye examination in the previous 2-years (OR = 2.06) were associated with severe uncorrected refractive error among non-Indigenous participants.

CONCLUSIONS AND RELEVANCE

Increased public awareness of the importance of regular optometric examinations may be required in groups at high risk of severe uncorrected refractive error.

Properties of the Impact of Vision Impairment and Night Vision Questionnaires Among People With Intermediate Age-Related Macular Degeneration

Purpose

To explore the psychometric properties of the Impact of Vision Impairment (IVI-28) and Night Vision Questionnaires (NVQ-10) among people with intermediate age-related macular degeneration (iAMD).

Methods

Baseline responses were collected from 288 participants (aged 50-88 years, 74% female) in the Laser intervention in Early stages of Age-related macular Degeneration (LEAD) study in Australia and Northern Ireland. Psychometric properties (discrimination, ordering of thresholds, person separation, item miss-fit, and differential item functioning according to sex) were explored using grouped rating scale and partial credit models. Spearman's correlation was estimated to assess the association with measures of visual function (mean mesopic microperimetric sensitivity, best-corrected visual acuity, low-luminance visual acuity, and low-luminance deficit). The psychometric properties were then explored following recalibration of the instruments.

Results

In this homogenous population, ceiling effects caused by relatively high levels of functional vision were evident for both instruments. The IVI-28 and NVQ-10 displayed suboptimal discrimination between levels of functional vision in iAMD and poor targeting among people with iAMD. The correlation between ability scores and measures of visual function was mild. In general, the NVQ-10 showed superior psychometric properties to the IVI-28 among these participants. No significant improvement in reliability could be gained following recalibration.

Conclusions

Both instruments were designed for populations with more severe visual loss and poorly discriminate in this cohort of iAMD.

Translational Relevance

New instruments that can capture the subtle changes in functional vision that occur early in AMD are required to aid evaluation of emerging interventions for iAMD.

Bleb-associated endophthalmitis: Proportion, presentation, management and outcomes in Victoria, Australia

IMPORTANCE

Bleb-associated endophthalmitis is a potentially vision-threatening complication of trabeculectomy. With improvements in surgical technique and changing patterns of intraoperative antimetabolite use, a re-evaluation of the incidence of bleb-associated endophthalmitis is warranted.

BACKGROUND

To investigate changes in the incidence, presentation, management and outcomes of bleb-associated endophthalmitis between 1997 and 2015 in Victoria, Australia.

DESIGN

A retrospective cohort analysis.

PARTICIPANTS

Consecutive cases of bleb-associated endophthalmitis managed at the Royal Victorian Eye and Ear Hospital (RVEEH) between 1997 and 2015.

METHODS

Medical record review of consecutive cases of bleb-associated endophthalmitis and statistical analysis were performed.

MAIN OUTCOME MEASURES

Visual acuity, including loss of light perception, intraocular pressure, and need for further surgery.

RESULTS

Sixty-seven eyes with bleb-associated endophthalmitis (BAE) were identified. Of these, 41 had trabeculectomy performed in Victoria during the study period, over which time 11 129 trabeculectomies were performed. The proportion of BAE was stable over time (0.4%). The mean age at presentation was 73.7 ± 12.1 years old and the majority of patients were Caucasian (79.1%). The mean duration between glaucoma filtration surgery and the development of bleb-associated endophthalmitis was 3 years (Interquartile Range = 0.4-6.0 years). The cultures were positive in 71.6% of cases. Approximately 1 in 8 patients required enucleation. The final visual acuity was poor with a Snellen Visual Acuity (VA) of 6/60 or worse in two-thirds of patients.

CONCLUSIONS AND RELEVANCE

Bleb-associated endophthalmitis is an uncommon complication following glaucoma filtration surgery. The proportion has remained stable over time. Visual outcomes remain poor.

Diabetic retinopathy screening in incident diabetes mellitus type 2 in Germany between 2004 and 2013 - A prospective cohort study based on health claims data

OBJECTIVE

To assess factors associated with diabetic retinopathy (DR) screening uptake following a diagnosis of type 2 diabetes mellitus (type 2 diabetes) in Germany.

MATERIALS AND METHODS

A nationally representative prospective sample of individual-level health claims data for 250,000 members from Germany's largest public insurance provider in 2004-2013 was assessed. In the sample, 26,560 persons with incident type 2 diabetes were identified. Factors associated with subsequent DR screening were assessed using descriptive statistics, Kaplan-Meier estimator, and Cox regression analysis.

RESULTS

On average 27.6 visits to an ophthalmologist per 100 person-years in persons with incident type 2 diabetes occurred. Half of all incident cases (Kaplan-Meier estimator) had not seen an ophthalmologist after more than two years (2.25 years) following their diabetes diagnosis. In the multivariate analysis, an older age (from hazard ratio HR(70-74) = 0.93 [95%-CI: 0.89-0.97] to HR(90+) = 0.50 [95%-CI: 0.42-0.60] compared to persons aged 50-69 years) and a higher disability level (i.e. HR(disability level 3) = 0.30 [95%-CI: 0.25-0.36]) were associated with a lower likelihood, while female sex (HR = 1.12 [95%-CI: 1.08-1.15]), six or more comorbidities (HR = 1.26 [95%-CI: 1.15-1.37]), moderate (HR = 1.51 [95%-CI: 1.46-1.56]) or severe type 2 diabetes (HR = 1.53 [95%-CI: 1.45-1.61]) as well as being enrolled in a type 2 diabetes disease management program (HR = 1.78 [95%-CI: 1.69-1.87]) were associated with a higher likelihood of DR screening.

CONCLUSIONS

A high proportion of newly diagnosed persons with type 2 diabetes did not follow current German recommendations for DR screening, impeding timely detection and management of potential complications. This was more apparent among persons who were men, older or had a disability. The uptake of screening was considerably greater among those enrolled in a diseases management program. These factors need to be considered when planning DR screening services and/or referrals.

Relationship between reticular pseudodrusen and choroidal thickness in intermediate age-related macular degeneration

IMPORTANCE

Reticular pseudodrusen (RPD) is strongly associated with late age-related macular degeneration (AMD) but their aetiology remains unknown. RPD have been associated with reduced choroidal thickness (ChT) but most studies are limited by small sample size and varying severity of AMD.

BACKGROUND

To investigate the relationship between choroidal thickness and RPD in eyes with intermediate AMD (iAMD), controlling for variables known to influence ChT.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Participants were recruited from Centre for Eye Research Australia.

METHODS

Colour fundus photographs, fundus auto fluorescence, near-infrared and spectral-domain ocular coherence tomography (OCT) were graded for RPD. ChT was measured from enhanced-depth imaging OCT scans at the centre of fovea, 1500 and 3000 μm nasal, temporal, superior and inferior from centre of fovea.

MAIN OUTCOME MEASURES

ChT between RPD and non-RPD group.

RESULTS

A total of 297 eyes from 152 subjects were included. A total of 84 (28%) had RPD and were older than non-RPD group (75.1 ± 5.4 years and 68.7 ± 6.9 years, respectively; P < 0.001). In unadjusted analysis, the RPD group was significantly associated with thinner choroids across all measured locations (P ≤ 0.022). After adjustment for variables, the presence of RPD was no longer associated with ChT (P ≥ 0.132 for all locations) but age (P < 0.001) and refractive error (P = 0.002) remained significantly associated with ChT.

CONCLUSIONS AND RELEVANCE

Age and refractive error, rather than RPD, was significantly associated with reduced ChT in eyes with iAMD. Choroidal insufficiency may be a less important variable in RPD aetiology than previously considered.

Physical Activity and Age-related Macular Degeneration: A Systematic Literature Review and Meta-analysis

PURPOSE

To better understand the association, in a white population, of physical activity and age-related macular degeneration (AMD)-the main cause of irreversible severe vision loss in developed countries-given the suggestion that a healthy lifestyle may assist in delaying the onset and progression of AMD.

DESIGN

Systematic review and meta-analysis.

METHODS

Medline, EMBASE, and Google Scholar were systematically searched for studies up to May 2015. Reference lists of published articles were hand searched and study authors were contacted to provide additional data. Those in the lowest category of activity in each study were compared with all other participants to assess the association between physical activity and both early and late AMD using random-effects meta-analysis.

RESULTS

Nine studies (subject age range 30-97 years) were included in the meta-analysis. Physical activity was found to have a protective association with both early AMD (8 studies, n = 38 112, odds ratio (OR) 0.92, 95% confidence interval [CI] 0.86-0.98) and late AMD (7 studies, n = 28 854, OR 0.59, 95% CI 0.49-0.72).

CONCLUSIONS

Physical activity is associated with lower odds of early and late AMD in white populations. These findings have important implications, reinforcing the public health message of staying active throughout life. However, further longitudinal studies are required to confirm and further characterize a protective effect of physical activity on the onset and/or progression of AMD.

Survival Bias When Assessing Risk Factors for Age-Related Macular Degeneration: A Tutorial with Application to the Exposure of Smoking

PURPOSE

We illustrate the effect of survival bias when investigating risk factors for eye disease in elderly populations for whom death is a competing risk. Our investigation focuses on the relationship between smoking and late age-related macular degeneration (AMD) in an observational study impacted by censoring due to death.

METHODS

Statistical methodology to calculate the survivor average causal effect (SACE) as a sensitivity analysis is described, including example statistical computing code for Stata and R. To demonstrate this method, we examine the causal effect of smoking history at baseline (1990-1994) on the presence of late AMD at the third study wave (2003-2007) using data from the Melbourne Collaborative Cohort Study.

RESULTS

Of the 40,506 participants eligible for inclusion, 38,092 (94%) survived until the start of the third study wave, 20,752 (51%) were graded for AMD (60% female, aged 47-85 years, mean 65 ± 8.7 years). Late AMD was detected in 122 participants. Logistic regression showed strong evidence of an increased risk of late AMD for current smokers compared to non-smokers (adjusted naïve odds ratio 2.99, 95% confidence interval, CI, 1.74-5.13). Among participants expected to be alive at the start of follow-up regardless of their smoking status, the estimated SACE odds ratio comparing current smokers to non-smokers was at least 3.42 (95% CI 1.57-5.15).

CONCLUSIONS

Survival bias can attenuate associations between harmful exposures and diseases of aging. Estimation of the SACE using a sensitivity analysis approach should be considered when conducting epidemiological research within elderly populations.