Longitudinal Associations Between Visual Impairment and Cognitive Functioning: The Salisbury Eye Evaluation Study

Importance

Worsening vision and declining cognitive functioning are common conditions among elderly individuals. Understanding the association between them could be beneficial in mitigating age-related cognitive changes.

Objective

To evaluate the longitudinal associations between visual impairment and cognitive function over time in a population-based study of older US adults.

Design, Setting, and Participants

Prospective longitudinal population-based study of older adults in the greater Salisbury area in Maryland. Overall, 2520 community-residing adults aged 65 to 84 years were assessed at baseline between September 1993 and August 1995 (round 1) and 2 (round 2), 6 (round 3), and 8 (round 4) years later.

Main Outcomes and Measures

Visual acuity (VA) was measured using Early Treatment Diabetic Retinopathy Study charts, and cognitive status was assessed using the Mini-Mental State Examination (MMSE).

Results

Of 2520 individuals, the mean (SD) age was 73.5 (5.1) years, 1458 (58%) were women, and 666 (26%) were black. There were 2240 (89%), 1504 (61%), and 1250 (50%) participants in the second, third, and fourth round of study, respectively, with more than half of the loss being due to death. Both VA and MMSE score worsened over time. The mean biannual decline of VA was 0.022 logMAR (approximately 1 line during 8 years; 95% CI, 0.018-0.026), and the mean biannual worsening of MMSE score was -0.59 (95% CI, -0.64 to -0.54; both P < .001). Worse baseline VA was associated with worse baseline MMSE score (r = -0.226; 95% CI, -0.291 to -0.16; P < .001). The rate of worsening VA was associated with the rate of declining MMSE score (r = -0.139; 95% CI, -0.261 to -0.017; P = .03). Cross-lagged models indicated VA in the previous round was associated with MMSE score in the subsequent round (β = -0.995, P < .001), and MMSE score in the previous round was associated with VA in the following round (β = -0.003, P < .001). However, the standardized effect size of VA on MMSE score (β = -0.074; SE, 0.015; P < .001) is larger relative to the reverse effect (β = -0.038; SE, 0.013; P < .001), demonstrating VA is likely the driving force in these dynamic associations.

Conclusions and Relevance

In a population-based sample of older US adults, visual impairment measured at distance is associated with declining cognitive function both cross-sectionally and longitudinally over time with worsening vision having a stronger association with declining cognition than the reverse. Worsening vision in older adults may be adversely associated with future cognitive functioning. Maintaining good vision may be an important interventional strategy for mitigating age-related cognitive declines.

Visualization of Focal Thinning of the Ganglion Cell-Inner Plexiform Layer in Patients with Mild Cognitive Impairment and Alzheimer's Disease

BACKGROUND

A detailed analysis of the tomographic thickness of intraretinal layers may provide more information on neurodegeneration in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD).

OBJECTIVE

The goal was to analyze tomographic thickness patterns of intraretinal layers in patients with AD andMCI.

METHOD

Forty-nine patients (25 AD and 24 MCI) and 21 cognitively normal (CN) controls were imaged using ultra-high-resolution optical coherence tomography to obtain volumetric data centered on the fovea. The segmented intraretinal layers were retinal nerve fiber layer (RNFL), ganglion cell- inner plexiform layer (GCIPL), inner nuclear layer (INL), outer nuclear layer (ONL), outer plexiform layer (OPL), and retinal photoreceptor (PR), in addition to the total retinal thickness(TRT).

RESULTS

The thickness differences were negative (thinning) mainly in TRT, RNFL, and GCIPL in both AD and MCI groups in comparison to CN, while the thickness differences were positive (thickening) mainly in ONL and PR in AD. GCIPL of AD and MCI was thinner in superior, nasal superior, and temporal superior quadrants, compared to CN (p < 0.05). GCIPL of the inner superior, inner nasal superior, inner temporal superior, and outer nasal superior sectors was significantly thinner in AD than CN (p < 0.05). GCIPL of the outer superior, inner temporal superior, outer nasal, and temporal superior sectors was significantly thinner in MCI than CN (p < 0.05).

CONCLUSION

Focal thinning of the GCIPL was visualized and quantified by detailed partitions in AD and MCI, which provides specific information about neurodegeneration in MCI and AD.

Assessing nonsedated handheld cone flicker electroretingram as a screening test in pediatric patients: comparison to sedated conventional cone flicker electroretinogram

PURPOSE

To assess the RETeval (LKC Technologies, Gaithersburg, MD) handheld electroretingram (ERG) device as a screening tool for cone dysfunction in pediatric patients by comparing it to conventional ERG.

METHODS

Patients scheduled for ERG under general anesthesia (GA) underwent three tests: (1) RETeval standard 30 Hz cone flicker ERG using skin electrodes prior to GA, (2) E3 Diagnosys (Diagnosys LLC, Lowell, MA) conventional complete standard protocol full-field ERG using bipolar contact lens electrodes and handheld stimulus under GA, and (3) repeat RETeval testing under GA. The 30 Hz cone flicker amplitudes and implicit times from the three methods were compared. Negative and positive predictive values were calculated by applying a previously established 5 μV amplitude cut-off.

RESULTS

Thirty patients ≤18 years of age were enrolled. Impaired conventional ERGs were found in 18 patients. Compared to conventional ERG under GA, RETeval cone flicker amplitudes were smaller before GA (mean difference, -42.2 ± 45.3 μV) and under GA (-37.1 ± 44.5 μV), likely due to skin electrode; and implicit times were shorter before GA (-1.06 ± 2.83 ms) and longer under GA (1.28 ± 4.12 ms), likely due to GA. Comparing RETeval responses before and under GA, the amplitudes were lower (-3.05 ± 6.82 μV), and implicit times were shorter (-2.25 ± 3.28 μV) before GA. Overall, the positive predictive value of the RETeval was 85%; the negative predictive value, 90%.

CONCLUSIONS

The unsedated handheld RETeval 30 Hz cone flicker ERG is a feasible screening test for detecting cone dysfunction in pediatric patients. Full-protocol ERG is needed when screening ERG is reduced, equivocal, or clinically warranted.

Adeno-Associated Viral Gene Therapy for Inherited Retinal Disease

Inherited retinal diseases (IRDs) are a group of rare, heterogenous eye disorders caused by gene mutations that result in degeneration of the retina. There are currently limited treatment options for IRDs; however, retinal gene therapy holds great promise for the treatment of different forms of inherited blindness. One such IRD for which gene therapy has shown positive initial results is choroideremia, a rare, X-linked degenerative disorder of the retina and choroid. Mutation of the CHM gene leads to an absence of functional Rab escort protein 1 (REP1), which causes retinal pigment epithelium cell death and photoreceptor degeneration. The condition presents in childhood as night blindness, followed by progressive constriction of visual fields, generally leading to vision loss in early adulthood and total blindness thereafter. A recently developed adeno-associated virus-2 (AAV2) vector construct encoding REP1 (AAV2-REP1) has been shown to deliver a functional version of the CHM gene into the retinal pigment epithelium and photoreceptor cells. Phase 1 and 2 studies of AAV2-REP1 in patients with choroideremia have produced encouraging results, suggesting that it is possible not only to slow or stop the decline in vision following treatment with AAV2-REP1, but also to improve visual acuity in some patients.

Choroideremia Gene Therapy Phase 2 Clinical Trial: 24-Month Results

PURPOSE

To report the final results of a phase 2 high-dose gene therapy clinical trial in choroideremia.

METHODS

Design: Phase 2 clinical trial.

PARTICIPANTS

Six men (aged 32-72 years) with genetically-confirmed advanced choroideremia. Patients received subfoveal injection of AAV2-REP1 (10¹¹ genome particles in 0.1 mL) in the worse-sighted eye.

OUTCOME MEASURES

Primary measure was best-corrected visual acuity (BCVA) change from baseline in the treated eye compared to the untreated eye. Secondary endpoints included change from baseline in microperimetry, fundus autofluorescence, and spectral-domain optical coherence tomography (OCT). Safety evaluations included adverse events, viral shedding in body fluids, and vector antibody responses.

RESULTS

Baseline mean ETDRS BCVA was 65.3 ± 8.8 (SD, range 56-77, 20/32-20/80) letters in the treated eyes and 77.0 ± 4.2 (69-81, 20/25-20/40) letters in the untreated eyes. At 2 years, 1 treated eye improved by 10 letters and another by 5 letters, while 1 untreated eye improved by 4 letters. All other eyes were within 2 letters of baseline. Baseline microperimetry sensitivities in the treated eyes were poor (1.2 ± 2.1 (0, 5.1) dB) and showed no significant change. No serious adverse event occurred. Two patients developed an atrophic retinal hole in a nonfunctioning macular area where baseline OCT showed preexisting thinning. Intraoperative microscope-integrated OCT allowed proper subretinal injection with avoidance of excessive foveal stretching and macular hole formation.

CONCLUSIONS

Sustained improvement or maintenance of BCVA is achievable in choroideremia with high-dose AAV2-REP1, indicating BCVA is a viable primary outcome in advanced choroideremia. Choroideremia gene therapy delivered with intraoperative OCT has a good safety profile.

Non-Arteritic Anterior Ischemic Optic Neuropathy in Pilots

BACKGROUND: Non-arteritic anterior ischemic optic neuropathy (NAION) is a common cause of optic neuropathy with the exact pathophysiology unknown. Risk factors include advanced age, small optic nerve head, hypertension, diabetes mellitus, and sleep apnea.⁶ High altitude is considered another risk factor, although only few cases have been reported. No cases of NAION have been reported to occur during flight.CASE REPORT: A 41-yr-old male pilot presented with vision change while performing high G-force maneuvers in an A10 fighter jet. He developed a paracentral visual field defect superiorly in the left eye. Contrasted MRI was within normal limits. The left optic nerve showed blurred margins while the right was sharp, but cupless. The left eye had similar episodes 16 mo before and 8 mo after, but not during flight.DISCUSSION: Our case may be the first reported NAION during flight in an airplane pilot. Our patient was an active U.S. Air Force pilot whose second episode of NAION occurred while performing maneuvers in a fighter jet. The patient is younger than expected for NAION and he did not have any of the commonly associated risk factors. His nonflight episodes suggest he was predisposed to NAION. G-force maneuvers, which restrict blood flow and force blood to the extremities away from the optic nerve head, were the precipitant of his second NAION. With a single case, whether high G maneuvers in general are a risk factor for NAION is unknown.Distefano AG, Lam BL. Non-arteritic anterior ischemic optic neuropathy in pilots. Aerosp Med Hum Perform. 2018; 89(11):1005-1007.

Automated instrument designed to determine visual photosensitivity thresholds

The Ocular Photosensitivity Analyzer (OPA), a new automated instrument to quantify the visual photosensitivity thresholds (VPT) in healthy and light sensitive subjects, is described. The OPA generates light stimuli of varying intensities utilizing unequal ascending and descending steps to yield the VPT. The performance of the OPA was evaluated in healthy subjects, as well as light sensitive subjects with achromatopsia or traumatic brain injury (TBI). VPT in healthy, achromatopsia, and TBI subjects were 3.2 ± 0.6 log lux, 0.5 ± 0.5 log lux, and 0.4 ± 0.6 log lux, respectively. Light sensitive subjects manifested significantly lower VPT compared to healthy subjects. Longitudinal analysis revealed that the OPA reliably measured VPT in healthy subjects.

Macular spatial distribution of preserved autofluorescence in patients with choroideremia

BACKGROUND/AIMS

To better understand the pattern of degeneration progression in cases with choroideremia.

METHODS

A cohort of genotypically confirmed choroideremia cases who underwent optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging was studied. Using HEYEX review software, the foveal centre was marked on FAF images under guidance of corresponding OCT images, followed by application of an ETDRS grid. The boundaries of preserved autofluorescence (AF) were manually segmented in each individual ETDRS subfield. The regional distribution of preserved AF was assessed by comparing its area among the various subfields.

RESULTS

A total of 168 eyes from 84 choroideremia cases were enrolled. There was a statistically significant difference in the amount of preserved AF area between inner subfields as determined by one-way analysis of variance (F (3,668)=9.997, p<0.001) and also between outer subfields (F (3,668)=8.348, p<0.001). A Tukey posthoc test revealed that the preserved AF area in the nasal subfields in both the inner and outer subfields was significantly smaller compared with analogue subfields.

CONCLUSION

The asymmetric spatial distribution of preserved AF in choroideremia (corresponding to the stellate shaped nature of these regions) suggests that the progression of degeneration has directional preference.

Swept-Source Optical Coherence Tomography Angiography of an Amalric Choroidal Infarction in a Rare Presentation of Giant Cell Arteritis With Bilateral Corneal Edema

A 73-year-old woman with 2 weeks of progressive painless vision loss was found to have bilateral corneal edema, jaw claudication, and temporal headache. Multimodal imaging revealed an Amalric choroidal infarct in the left eye visualized by widefield indocyanine green angiography and swept-source optical coherence tomography angiography (SS-OCTA). Prompt intravenous corticosteroid treatment resulted in 20/20 vision, and giant cell arteritis (GCA) was confirmed by a temporal artery biopsy. The case underscores the use of widefield SS-OCTA as a non-invasive test to aid in the diagnosis of GCA, as well as bilateral cornea edema as a rare presentation of GCA. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e157-e160.].

Stargardt macular dystrophy and evolving therapies

INTRODUCTION

Stargardt macular dystrophy (STGD1) is a hereditary retinal degeneration that lacks effective treatment options. Gene therapy, stem cell therapy, and pharmacotherapy with visual cycle modulators (VCMs) and complement inhibitors are discussed as potential treatments.

AREAS COVERED

Investigational therapies for STGD1 aim to reduce toxic bisretinoids and lipofuscin in the retina and retinal pigment epithelium (RPE). These agents include C20-D3-vitamin A (ALK-001), isotretinoin, VM200, emixustat, and A1120. Avacincaptad pegol is a C5 complement inhibitor that may reduce inflammation-related RPE damage. Animal models of STGD1 show promising data for these treatments, though proof of efficacy in humans is lacking. Fenretinide and emixustat are VCMs for dry AMD and STGD1 that failed to halt geographic atrophy progression or improve vision in trials for AMD. A1120 prevents retinol transport into RPE and may spare side effects typically seen with VCMs (nyctalopia and chromatopsia). Stem cell transplantation suggests potential biologic plausibility in a phase I/II trial. Gene therapy aims to augment the mutated ABCA4 gene, though results of a phase I/II trial are pending.

EXPERT OPINION

Stem cell transplantation, ABCA4 gene therapy, VCMs, and complement inhibitors offer biologically plausible treatment mechanisms for treatment of STGD1. Further trials are warranted to assess efficacy and safety in humans.

Retinal Anatomy and Electrode Array Position in Retinitis Pigmentosa Patients After Argus II Implantation: An International Study

PURPOSE

To assess the retinal anatomy and array position in Argus II retinal prosthesis recipients.

DESIGN

Prospective, noncomparative cohort study.

METHODS

Setting: International multicenter study.

PATIENTS

Argus II recipients enrolled in the Post-Market Surveillance Studies.

PROCEDURES

Spectral-domain optical coherence tomography images collected for the Surveillance Studies (NCT01860092 and NCT01490827) were reviewed. Baseline and postoperative macular thickness, electrode-retina distance (gap), optic disc-array overlap, and preretinal membrane presence were recorded at 1, 3, 6, and 12 months.

MAIN OUTCOME MEASURES

Axial retinal thickness and axial gap along the array's long axis (a line between the tack and handle); maximal retinal thickness and maximal gap along a B-scan near the tack, midline, and handle.

RESULTS

Thirty-three patients from 16 surgical sites in the United States and Germany were included. Mean axial retinal thickness increased from month 1 through month 12 at each location, but reached statistical significance only at the array midline (P = .007). The rate of maximal thickness increase was highest near the array midline (slope = 6.02, P = .004), compared to the tack (slope = 3.60, P < .001) or the handle (slope = 1.93, P = .368). The mean axial and maximal gaps decreased over the study period, and the mean maximal gap size decrease was significant at midline (P = .032). Optic disc-array overlap was seen in the minority of patients. Preretinal membranes were common before and after implantation.

CONCLUSIONS

Progressive macular thickening under the array was common and corresponded to decreased electrode-retina gap over time. By month 12, the array was completely apposed to the macula in approximately half of the eyes.

REPEATABILITY AND LONGITUDINAL ASSESSMENT OF FOVEAL CONE STRUCTURE IN CNGB3-ASSOCIATED ACHROMATOPSIA

PURPOSE

Congenital achromatopsia is an autosomal recessive disease causing substantial reduction or complete absence of cone function. Although believed to be a relatively stationary disorder, questions remain regarding the stability of cone structure over time. In this study, the authors sought to assess the repeatability of and examine longitudinal changes in measurements of central cone structure in patients with achromatopsia.

METHODS

Forty-one subjects with CNGB3-associated achromatopsia were imaged over a period of between 6 and 26 months using optical coherence tomography and adaptive optics scanning light ophthalmoscopy. Outer nuclear layer (ONL) thickness, ellipsoid zone (EZ) disruption, and peak foveal cone density were assessed.

RESULTS

ONL thickness increased slightly compared with baseline (0.184 μm/month, P = 0.02). The EZ grade remained unchanged for 34/41 subjects. Peak foveal cone density did not significantly change over time (mean change 1% per 6 months, P = 0.126).

CONCLUSION

Foveal cone structure showed little or no change in this group of subjects with CNGB3-associated achromatopsia. Over the time scales investigated (6-26 months), achromatopsia seems to be a structurally stable condition, although longer-term follow-up is needed. These data will be useful in assessing foveal cone structure after therapeutic intervention.

Nonsedated handheld electroretinogram as a screening test of retinal dysfunction in pediatric patients with nystagmus

PURPOSE

To assess the feasibility, sensitivity, and specificity of nonsedated handheld cone flicker electroretinogram (ERG) as a screening tool to detect retinal dysfunction in children with nystagmus.

METHODS

Pediatric patients at a tertiary referral center from December 2015 to July 2016 were enrolled and placed into three age-matched groups: normal, nystagmus with a retinal dystrophy, and nystagmus without a retinal dystrophy. Unsedated 30 Hz cone flicker ERG responses were obtained using a handheld device (RETeval) from both eyes of each patient using skin electrode sensors after pupillary dilation.

RESULTS

A total of 71 children were enrolled; amplitudes and implicit times were successfully obtained in 65 (92%): 31 (mean age ± SD, 5.6 ± 2.7 years; range, 1-12 years) without nystagmus and 34 with nystagmus. Nystagmus patients were grouped by those with (n = 15; mean age, 8.5 ± 4.5 [range, 2-17 years) and without (n = 19; mean age, 4.3 ± 3.0 [range, 6 months-10 years]) a retinal dystrophy. The patients with retinal dystrophies had significantly smaller amplitudes and prolonged or nonmeasurable implicit times than the other two groups (P < 0.001). Among nystagmus patients, amplitude was able to discriminate between those with and without retinal dystrophies with area under curve of 0.986 (SE = 0.016; P < 0.001). An amplitude <5 μV in combination with an implicit time of >33 ms warrants further evaluation.

CONCLUSIONS

Unsedated handheld cone flicker ERG is a feasible screening test that effectively detects retinal dysfunction in children with nystagmus. In conjunction with clinical findings, the test helps reduce the need for sedated ERG in children.

Eye Health Knowledge and Eye Health Information Exposure Among Hispanic/Latino Individuals: Results From the Hispanic Community Health Study/Study of Latinos

Importance

Routine eye care is important to maintaining eye health and preventing visual impairment. However, poor knowledge of ocular risk factors and disease as well as minimal exposure to eye health information may compromise adherence to eye care recommendations. Studies have shown that Hispanic/Latino people have poor eye care utilization, but little is known about their knowledge of eye health and exposure to eye health information.

Objective

To examine factors associated with more eye health knowledge and greater exposure to eye health information among Hispanic/Latino people.

Design, Setting, and Participants

This was a cross-sectional ocular study of 1235 participants living in the Miami, Florida, site of the Hispanic Community Health Study/Study of Latinos, a multisite epidemiologic study of disease prevalence and development among Hispanic/Latino people. Data were collected from October 1, 2011, through September 30, 2013, and data analyses were conducted between May 28, 2014, and March 18, 2015. Descriptive and multivariable regression analyses were performed for 3 ocular health care outcomes. Regression models were built sequentially, with variables conceptually grouped according to Andersen's Behavioral Model of Health Services Use and Behavioral Model for Vulnerable Populations.

Main Outcomes and Measures

Ability to identify 8 factors on a general eye health knowledge scale and number of eye health information sources seen or heard about in the past 12 months.

Results

Of the 1235 participants, 748 (73.4%) self-identified as being of Cuban descent and 407 (19.2%) self-identified as being from Central or South America, 478 (46.7%) were women and 757 (53.3%) were men, and the mean (SD) age was 53.6 (8.1) years. Participants with at least a high school degree or general educational development certificate had greater eye health knowledge (incidence rate ratio [IRR], 1.08; 95% CI, 1.01-1.15 and IRR, 1.11; 95% CI, 1.04-1.17, respectively) as did those with a higher mental health score on the Short Form 12-Item, version 2, Health Survey (IRR, 1.03; 95% CI, 1.01-1.04). Those with educational attainment beyond a high school degree or a general educational development certificate (IRR, 1.29; 95% CI, 1.07-1.54), those who were 60 years or older (IRR, 1.32; 95% CI, 1.06-1.63), and those with a household income in US dollars of $20 001 to $40 000 (IRR, 1.23; 95% CI, 1.05-1.44) or greater than $40 000 (IRR, 1.25; 95% CI, 0.98-1.59) were more likely to be exposed to at least 5 sources of eye health information in the past 12 months.

Conclusions and Relevance

Among Hispanic/Latino people, age, educational level, income, and mental health may be important correlates of eye disease knowledge and eye health information exposure. These findings might be used to support the development of targeted interventions designed to improve eye health in this population.

New Methods for Quantification of Visual Photosensitivity Threshold and Symptoms

PURPOSE

Visual photosensitivity is a common symptom difficult to measure and diagnose, and is found in many ocular and neurological disorders. We developed two novel reproducible quantitative assessments of visual photosensitivity.

METHODS

We designed and built the ocular photosensitivity analyzer (OPA), an automated instrument to determine light intensity visual photosensitivity threshold (VPT), and developed the Visual Light Sensitivity Questionnaire-8 (VLSQ-8), an eight-question survey to assess the presence and severity of photosensitivity symptoms. We evaluated the test-retest variability and obtained normative values of these two approaches in 35 healthy normal subjects, distributed evenly over five age groups from eight to 60 years. Each subject underwent two test sessions, each with VLSQ-8, eye examination, and OPA, four weeks apart, between April 2015 and June 2016.

RESULTS

Log-transformed VPTs (log₁₀lux) and VLSQ-8 results were highly reproducible between the two sessions (VPT intraclass correlation coefficient [ICC] = 0.86; 95% confidence interval [CI] = 0.71-0.93; binocular testing, VLSQ-items ICC range = 0.53-0.87). No consistent significant differences in VPTs were found with monocular (P = 0.053, session 1) or binocular (P = 0.26) testing. Subjects in age group >30 to 40 years had significantly higher VPTs than those in other age groups (P ≤ 0.011) except the >40 to 50 years age group (P = 0.11). Photosensitivity symptoms assessed by the VLSQ-8 generally were low and highly reproducible with ≥88% of responses between the 2 sessions being within one category of each other.

CONCLUSIONS

Our results provide reliability data and normative results toward validation of two novel approaches to quantify visual photosensitivity and provide support for their potential use in ocular and neurologic conditions as well as in clinical trials.

TRANSLATIONAL RELEVANCE

The new quantitative photosensitivity approaches are potential measures to characterize disease severity, monitor disease progression, and evaluate treatment efficacy.

Measurement and Reproducibility of Preserved Ellipsoid Zone Area and Preserved Retinal Pigment Epithelium Area in Eyes With Choroideremia

PURPOSE

To identify valid and reproducible methods for quantifying anatomic outcome measures for eyes with choroideremia (CHM) in clinical trials.

DESIGN

Reliability analysis study.

METHODS

In this multicenter study, patients with confirmed genetic diagnosis of CHM were enrolled. All cases underwent spectral-domain optical coherence tomography (SDOCT) and fundus autofluorescence (FAF) imaging. Two graders independently delineated boundaries of preserved autofluorescence (PAF) and preserved ellipsoid zone (EZ) on FAF and OCT images, respectively. The results of the 2 independent gradings of both FAF and OCT images were compared to assess the reproducibility of the grading methods.

RESULTS

A total of 148 eyes from 75 cases were included. In 21% of eyes PAF and in 43% of eyes preserved EZ had extended beyond the image capture area. After exclusion of these eyes and low-quality images, 114 FAF and 77 OCT images were graded. The mean PAF areas from 2 independent gradings were 3.720 ± 3.340 mm² and 3.692 ± 3.253 mm², respectively. Intraclass correlation coefficient (ICC) for these gradings was 0.996. The mean preserved EZ areas from 2 independent gradings were 2.746 ± 2.319 mm² and 2.858 ± 2.446 mm², respectively. ICC for these gradings was 0.991.

CONCLUSIONS

Quantifying preserved retinal pigment epithelium and EZ areas on FAF and OCT images, respectively, in CHM patients is highly reproducible. These variables would be potential anatomic outcome measures for CHM clinical trials and could be studied and tracked longitudinally in choroideremia.