Features Associated With Vision in Eyes With Subfoveal Fibrosis From Neovascular Age-Related Macular Degeneration

PURPOSE

To report the characteristics and correlation of visual acuity in eyes treated for neovascular age-related macular degeneration (nAMD) and developed fibrosis.

DESIGN

Case-control study.

METHODS

Three hundred fifty-six treatment-naive nAMD eyes that were treated for 12 months were included. Fibrosis was defined as present if well-defined hyperreflective material (HRM) were present between the neurosensory retina and the Bruch membrane on optical coherence tomography (OCT) that correlated with well-defined regions of yellowish pallor on fundus photography and/or staining on fluorescence angiography. OCT features of subfoveal fibrosis and the overlying retina were correlated with visual acuity at month 12.

RESULTS

Sixty-three eyes (20.3%) developed incident fibrosis at month 12. Compared with eyes that did not develop fibrosis, these eyes had lower baseline vision (49 vs 54 letters, P = .02) and more of them had type 2 macular neovascularization (15.0 vs 8.8%, P = .03), larger lesion area (29.6 vs 15.1 mm2, P = .02), and subretinal hemorrhage ≥4 disc diameters (44.4% vs 19.8%, P < .01). Visual acuity was worse in the incident fibrosis compared with the group that never developed fibrosis by month 12. (-1.4±17.1 versus +6.0±17.4 letters, P < .01). In 83 eyes that had subfoveal fibrosis, better vision was associated with intact ellipsoid zone-external limiting membrane complex (β coefficient 29.4, 95% CI 14.2-44.6, P < .01), whereas worse vision was associated with retinal pigment epithelium (RPE)-involving HRM, HRM above the RPE, and width of HRM (β coefficients -25.4 [95% CI -36.3 to -14.6], P < .01; -23.5 [95% CI -39.0 to -7.9], P < .01; and -3.8 [95% CI -7.2 to -0.4], P = .03, respectively).

CONCLUSION

Although fibrosis is associated with poorer visual outcome, preservation of external limiting membrane and level of fibrosis relative to the RPE are associated with visual outcomes.

Defining the structure-function relationship of specific lesions in early and advanced age-related macular degeneration

The objective of this study is to define structure-function relationships of pathological lesions related to age-related macular degeneration (AMD) using microperimetry and multimodal retinal imaging. We conducted a cross-sectional study of 87 patients with AMD (30 eyes with early and intermediate AMD and 110 eyes with advanced AMD), compared to 33 normal controls (66 eyes) recruited from a single tertiary center. All participants had enface and cross-sectional optical coherence tomography (Heidelberg HRA-2), OCT angiography, color and infra-red (IR) fundus and microperimetry (MP) (Nidek MP-3) performed. Multimodal images were graded for specific AMD pathological lesions. A custom marking tool was used to demarcate lesion boundaries on corresponding enface IR images, and subsequently superimposed onto MP color fundus photographs with retinal sensitivity points (RSP). The resulting overlay was used to correlate pathological structural changes to zonal functional changes. Mean age of patients with early/intermediate AMD, advanced AMD and controls were 73(SD = 8.2), 70.8(SD = 8), and 65.4(SD = 7.7) years respectively. Mean retinal sensitivity (MRS) of both early/intermediate (23.1 dB; SD = 5.5) and advanced AMD (18.1 dB; SD = 7.8) eyes were significantly worse than controls (27.8 dB, SD = 4.3) (p < 0.01). Advanced AMD eyes had significantly more unstable fixation (70%; SD = 63.6), larger mean fixation area (3.9 mm2; SD = 3.0), and focal fixation point further away from the fovea (0.7 mm; SD = 0.8), than controls (29%; SD = 43.9; 2.6 mm2; SD = 1.9; 0.4 mm; SD = 0.3) (p ≤ 0.01). Notably, 22 fellow eyes of AMD eyes (25.7 dB; SD = 3.0), with no AMD lesions, still had lower MRS than controls (p = 0.04). For specific AMD-related lesions, end-stage changes such as fibrosis (5.5 dB, SD = 5.4 dB) and atrophy (6.2 dB, SD = 7.0 dB) had the lowest MRS; while drusen and pigment epithelial detachment (17.7 dB, SD = 8.0 dB) had the highest MRS. Peri-lesional areas (20.2 dB, SD = 7.6 dB) and surrounding structurally normal areas (22.2 dB, SD = 6.9 dB) of the retina with no AMD lesions still had lower MRS compared to controls (27.8 dB, SD = 4.3 dB) (p < 0.01). Our detailed topographic structure-function correlation identified specific AMD pathological changes associated with a poorer visual function. This can provide an added value to the assessment of visual function to optimize treatment outcomes to existing and potentially future novel therapies.

The Natural History of Retinal Sensitivity Loss in Diabetic Macular Ischemia over One Year Evaluated by Microperimetry

Background/Objectives: This one-year prospective observational study, conducted at two centers, aimed to report the natural history of retinal sensitivity (RS) loss in diabetic macular ischemia (DMI). Methods: Patients with stable-treated proliferative diabetic retinopathy (PDR) were recruited if there was evidence of DMI on optical coherence tomography angiography, defined as a foveal avascular zone ≥ 0.5 mm2 or parafoveal capillary dropout ≥ 1 quadrant. The minimal visual acuity required for performing microperimetry (MP) was ≥54 Early Treatment Diabetic Retinopathy Study letters (Snellen equivalent 20/80). The overall RS (oRS) and pointwise sensitivity (PWS) within the 3 × 3 mm macula were assessed at baseline and twelve months. A value <25 decibels (dB) was defined as impaired RS, and a decrease of 2 and 7 dB was regarded as mild and severe loss, respectively. Results: A total of 88 patients (97 eyes) were included. No statistically significant MP changes were detected at one year. However, 10% of the cohort lost oRS ≥ 2 dB, and 73% lost ≥2 dB PWS in ≥5 loci, whereas 1% lost oRS ≥ 7 dB, and 4% lost ≥7 dB PWS in ≥5 loci. The foveola and temporal parafovea were the most vulnerable to severe RS loss. Compared to their counterpart, eyes with baseline oRS ≥ 25 dB had significantly more RS loss in the macula and superior parafovea (55% versus 32% and 53% versus 28%, both p = 0.01). Conclusions: Rather than oRS loss, ≥2 dB loss in PWS in ≥5 loci is a more feasible outcome measure for clinical trials in DMI.

Six-Year Outcomes in Subjects with Polypoidal Choroidal Vasculopathy in the EVEREST II Study

INTRODUCTION

The EVEREST II study previously reported that intravitreally administered ranibizumab (IVR) combined with photodynamic therapy (PDT) achieved superior visual gain and polypoidal lesion closure compared to IVR alone in patients with polypoidal choroidal vasculopathy (PCV). This follow-up study reports the long-term outcomes 6 years after initiation of the EVEREST II study.

METHODS

This is a non-interventional cohort study of 90 patients with PCV from 16 international trial sites who originally completed the EVEREST II study. The long-term outcomes were assessed during a recall visit at about 6 years from commencement of EVEREST II.

RESULTS

The monotherapy and combination groups contained 41 and 49 participants, respectively. The change in best-corrected visual acuity (BCVA) from baseline to year 6 was not different between the monotherapy and combination groups; - 7.4 ± 23.0 versus - 6.1 ± 22.4 letters, respectively. The combination group had greater central subfield thickness (CST) reduction compared to the monotherapy group at year 6 (- 179.9 vs - 74.2 µm, p = 0.011). Fewer eyes had subretinal fluid (SRF)/intraretinal fluid (IRF) in the combination versus monotherapy group at year 6 (35.4% vs 57.5%, p = 0.032). Factors associated with BCVA at year 6 include BCVA (year 2), CST (year 2), presence of SRF/IRF at year 2, and number of anti-VEGF treatments (years 2-6). Factors associated with presence of SRF/IRF at year 6 include combination arm (OR 0.45, p = 0.033), BCVA (year 2) (OR 1.53, p = 0.046), and presence of SRF/IRF (year 2) (OR 2.59, p = 0.042).

CONCLUSION

At 6 years following the EVEREST II study, one-third of participants still maintained good vision. As most participants continued to require treatment after exiting the initial trial, ongoing monitoring and re-treatment regardless of polypoidal lesion status are necessary in PCV.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT01846273.

Macular neovascularization and polypoidal choroidal vasculopathy: phenotypic variations, pathogenic mechanisms and implications in management

Advances in imaging have led to improved ability to characterize variations in clinical sub-phenotypes of macular neovascularization (MNV) in Age-related macular degeneration (AMD). Polypoidal choroidal vasculopathy (PCV) was initially described based on characteristic features observed in indocyanine green angiography (ICGA) and was thought to be a distinct entity from AMD. However, subsequent careful observations based on confocal scanning laser ophthalmoscopy-based ICGA, optical coherence tomography (OCT) and OCT angiography have led researchers to appreciate similarities between PCV lesion and type 1 MNV in typical neovascular AMD. Concurrently, clinical trials have shown that anti-VEGF monotherapy can achieve favourable visual outcome in the majority of eyes with PCV. These learnings have led to a shift in the way PCV is managed over the past decade. Recent studies have supported the use of non-ICGA based imaging modality to screen for PCV and the adoption of anti-VEGF monotherapy as initial therapy for PCV. A focus of recent research has been in the understanding of the role of choroidal alterations in the pathogenesis of PCV. The concept of pachychoroid in leading to outer retinal ischemia has garnered increasing support. Future research in this area should evaluate the potential of choroidal morphology in guiding personalized therapy in PCV.

Polypoidal Choroidal Vasculopathy: Evaluation Based on 3-Dimensional Reconstruction of OCT Angiography

OBJECTIVE

Three-dimensional (3D) reconstruction using swept-source OCT angiography (SS-OCTA) can provide insights into the nature and structure of polypoidal choroidal vasculopathy (PCV) and its component parts, the polypoidal lesion (PL) and the branching neovascular network (BNN). This study aims to describe novel observations of PCV using 3D reconstruction of SS-OCTA, and to compare these observations with similar images of type I macular neovascularization (MNV) typical neovascular age-related macular degeneration (nAMD).

DESIGN

Clinical case series.

SUBJECTS

Patients with PCV in either eye from clinical studies conducted in a tertiary retina center.

METHODS

Images with prespecified SS-OCTA imaging protocol were obtained and reconstructed in 3D. Forty neovascularization lesions (30 PCV and 10 typical nAMD) based on SS-OCTA were analyzed.

MAIN OUTCOME MEASURES

The following 3 specific features were evaluated: (1) the pattern of flow signal within the PLs as either homogenous or showing internal vascular architecture; (2) the configuration of the BNN as hypermature, mature, or immature; and (3) the spatial arrangement of the PLs in relation to the BNN. Comparisons were made between PCV and typical nAMD.

RESULTS

All PLs exhibited internal vascular architecture in the form of coil-like loops and none exhibited homogenous flow. Small focal nodules were present within this internal vascular architecture in 70% of PLs. Branching neovascular networks exhibited a hypermature/mature configuration (100 vs. 50%, P < 0.01) and were associated with thicker choroid compared with typical nAMD type 1 MNV (238.7 ± 104.3 vs. 155.6 ± 49.2, P = 0.02). The BNN and PL were located at distinct anteroposterior planes in 81% of the eyes.

CONCLUSIONS

We identified proliferating vasculature in both the PL and the BNN. Comparison of the configuration suggests that the BNN represents a more chronic and inactive lesion than the PL.

FINANCIAL DISCLOSURE(S)

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

Central serous chorioretinopathy: An evidence-based treatment guideline

Central serous chorioretinopathy (CSC) is a relatively common disease that causes vision loss due to macular subretinal fluid leakage and is often associated with reduced vision-related quality of life. In CSC, the leakage of subretinal fluid through defects in the retinal pigment epithelial layer's outer blood-retina barrier appears to occur secondary to choroidal abnormalities and dysfunction. The treatment of CSC is currently the subject of controversy, although recent data obtained from several large randomized controlled trials provide a wealth of new information that can be used to establish a treatment algorithm. Here, we provide a comprehensive overview of our current understanding regarding the pathogenesis of CSC, current therapeutic strategies, and an evidence-based treatment guideline for CSC. In acute CSC, treatment can often be deferred for up to 3-4 months after diagnosis; however, early treatment with either half-dose or half-fluence photodynamic therapy (PDT) combined with the photosensitive dye verteporfin may be beneficial in selected cases. In chronic CSC, half-dose or half-fluence PDT, which targets the abnormal choroid, should be considered the preferred treatment. If PDT is unavailable, chronic CSC with focal, non-central leakage on angiography may be treated using conventional laser photocoagulation. CSC with concurrent macular neovascularization should be treated with half-dose/half-fluence PDT and/or intravitreal injections of an anti-vascular endothelial growth factor compound. Given the current shortage of verteporfin and the paucity of evidence supporting the efficacy of other treatment options, future studies-ideally, well-designed randomized controlled trials-are needed in order to evaluate new treatment options for CSC.

Is Kidney Function Associated with Age-Related Macular Degeneration?: Findings from the Asian Eye Epidemiology Consortium

PURPOSE

Chronic kidney disease (CKD) may elevate susceptibility to age-related macular degeneration (AMD) because of shared risk factors, pathogenic mechanisms, and genetic polymorphisms. Given the inconclusive findings in prior studies, we investigated this association using extensive datasets in the Asian Eye Epidemiology Consortium.

DESIGN

Cross-sectional study.

PARTICIPANTS

Fifty-one thousand two hundred fifty-three participants from 10 distinct population-based Asian studies.

METHODS

Age-related macular degeneration was defined using the Wisconsin Age-Related Maculopathy Grading System, the International Age-Related Maculopathy Epidemiological Study Group Classification, or the Beckman Clinical Classification. Chronic kidney disease was defined as estimated glomerular filtration rate (eGFR) of less than 60 ml/min per 1.73 m2. A pooled analysis using individual-level participant data was performed to examine the associations between CKD and eGFR with AMD (early and late), adjusting for age, sex, hypertension, diabetes, body mass index, smoking status, total cholesterol, and study groups.

MAIN OUTCOME MEASURES

Odds ratio (OR) of early and late AMD.

RESULTS

Among 51 253 participants (mean age, 54.1 ± 14.5 years), 5079 had CKD (9.9%). The prevalence of early AMD was 9.0%, and that of late AMD was 0.71%. After adjusting for confounders, individuals with CKD were associated with higher odds of late AMD (OR, 1.46; 95% confidence interval [CI], 1.11-1.93; P = 0.008). Similarly, poorer kidney function (per 10-unit eGFR decrease) was associated with late AMD (OR, 1.12; 95% CI, 1.05-1.19; P = 0.001). Nevertheless, CKD and eGFR were not associated significantly with early AMD (all P ≥ 0.149).

CONCLUSIONS

Pooled analysis from 10 distinct Asian population-based studies revealed that CKD and compromised kidney function are associated significantly with late AMD. This finding further underscores the importance of ocular examinations in patients with CKD.

FINANCIAL DISCLOSURE(S)

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

Relationship Between Retinal Layer Thickness and Genetic Susceptibility to Age-Related Macular Degeneration in Asian Populations

Purpose

For OCT retinal thickness measurements to be used as a prodromal age-related macular degeneration (AMD) risk marker, the 3-dimensional (3D) topographic variation of the relationship between genetic susceptibility to AMD and retinal thickness needs to be assessed. We aimed to evaluate individual retinal layer thickness changes and topography at the macula that are associated with AMD genetic susceptibility.

Design

Genetic association study.

Participants

A total of 1579 healthy participants (782 Chinese, 353 Malays, and 444 Indians) from the multiethnic Singapore Epidemiology of Eye Diseases study were included.

Methods

Spectral-domain OCT and automatic segmentation of individual retinal layers were performed to produce 10 retinal layer thickness measurements at each ETDRS subfield, producing 3D topographic information. Age-related macular degeneration genetic susceptibility was represented via single nucleotide polymorphisms (SNPs) and aggregated via whole genome (overall) and pathway-specific age-related macular degeneration polygenic risk score (PRSAMD).

Main Outcome Measures

Associations of individual SNPs, overall PRSAMD, and pathway-specific PRSAMD with retinal thickness were analyzed by individual retinal layer and ETDRS subfield.

Results

CFH rs10922109, ARMS2-HTRA1 rs3750846, and LIPC rs2043085 were the top AMD susceptibility SNPs associated with retinal thickness of individual layers (P < 1.67 × 10-3), all at the central subfield. The overall PRSAMD was most associated with thinner L9 (outer segment photoreceptor/retinal pigment epithelium complex) thickness at the central subfield (β = -0.63 μm; P = 5.45 × 10-9). Pathway-specific PRSAMD for the complement cascade (β = -0.53 μm; P = 9.42 × 10-7) and lipoprotein metabolism (β = -0.05 μm; P = 0.0061) were associated with thinner photoreceptor layers (L9 and L7 [photoreceptor inner/outer segments], respectively) at the central subfield. The mean PRSAMD score was larger among Indians compared with that of the Chinese and had the thinnest thickness at the L9 central subfield (β = -1.00 μm; P = 2.91 × 10-7; R2 = 5.5%). Associations at other retinal layers and ETDRS regions were more heterogeneous.

Conclusions

Overall genetic susceptibility to AMD and the aggregate effects of the complement cascade and lipoprotein metabolism pathway are associated most significantly with L7 and L9 photoreceptor thinning at the central macula in healthy individuals. Photoreceptor thinning has potential to be a prodromal AMD risk marker, and topographic variation should be considered.

Financial Disclosures

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

The economic burden of inherited retinal disease in Singapore: a prevalence-based cost-of-illness study

OBJECTIVE

To assess the economic impact of inherited retinal disease (IRD) among Singaporeans.

METHODS

IRD prevalence was calculated using population-based data. Focused surveys were conducted for sequentially enrolled IRD patients from a tertiary hospital. The IRD cohort was compared to the age- and gender-matched general population. Economic costs were expanded to the national IRD population to estimate productivity and healthcare costs.

RESULTS

National IRD caseload was 5202 cases (95% CI, 1734-11273). IRD patients (n = 95) had similar employment rates to the general population (67.4% vs. 70.7%; p = 0.479). Annual income was lower among IRD patients than the general population (SGD 19,500 vs. 27,161; p < 0.0001). Employed IRD patients had lower median income than the general population (SGD 39,000 vs. 52,650; p < 0.0001). Per capita cost of IRD was SGD 9382, with a national burden of SGD 48.8 million per year. Male gender (beta of SGD 6543, p = 0.003) and earlier onset (beta of SGD 150/year, p = 0.009) predicted productivity loss. Treatment of the most economically impacted 10% of IRD patients with an effective IRD therapy required initial treatment cost of less than SGD 250,000 (USD 188,000) for cost savings to be achieved within 20 years.

CONCLUSIONS

Employment rates among Singaporean IRD patients were the same as the general population, but patient income was significantly lower. Economic losses were driven in part by male patients with early age of onset. Direct healthcare costs contributed relatively little to the financial burden.

Efficacy, durability, and safety of faricimab in patients from Asian countries with neovascular age-related macular degeneration: 1-Year subgroup analysis of the TENAYA and LUCERNE trials

PURPOSE

To evaluate 1-year efficacy, durability, and safety of faricimab among patients from Asian countries in the TENAYA/LUCERNE trials of neovascular age-related macular degeneration (nAMD).

METHODS

Treatment-naïve patients with nAMD were randomly assigned (1:1) to faricimab 6.0 mg up to every 16 weeks (Q16W), based on disease activity at weeks 20 and 24, or aflibercept 2.0 mg Q8W. The primary endpoint was change in best-corrected visual acuity (BCVA) from baseline averaged over weeks 40, 44, and 48.

RESULTS

In the pooled TENAYA/LUCERNE trials, there were 120 (9.0%) and 1209 (91.0%) patients in the Asian (faricimab n = 61; aflibercept n = 59) and non-Asian country (faricimab n = 604; aflibercept n = 605) subgroups, respectively. In the Asian country subgroup, mean BCVA change from baseline at the primary endpoint visits was 7.1 (95% CI, 4.3-9.8) letters with faricimab and 7.2 (4.4-10.0) letters with aflibercept. In non-Asian country patients, mean vision gains were 6.1 (5.2-7.1) and 5.7 (4.8-6.7) letters with faricimab and aflibercept, respectively. At week 48, 59.6% of Asian country patients in the faricimab group achieved Q16W dosing (vs. 43.9% non-Asian) and 91.2% achieved ≥ Q12W dosing (vs. 77.5% non-Asian). Central subfield thickness reductions were similar between the subgroups, with meaningful and similar reductions from baseline observed at the primary endpoint visits and over time. Faricimab was well tolerated in both subgroups, with an acceptable safety profile.

CONCLUSION

Consistent with the global TENAYA/LUCERNE findings, faricimab up to Q16W showed sustained visual and anatomical benefits in patients with nAMD from Asian and non-Asian countries.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03823287 (TENAYA); NCT03823300 (LUCERNE). Date of registration: January 30, 2019.

Visual acuity time in range: a novel concept to describe consistency in treatment response in diabetic macular oedema

OBJECTIVE

To assess 'time in range' as a novel measure of treatment response in diabetic macular oedema (DMO).

METHODS

This post hoc analysis of the Protocol T randomised clinical trial included 660 individuals with centre-involved DMO and best-corrected visual acuity (BCVA) letter score ≤78-≥24 (approximate Snellen equivalent 20/32-20/320). Study participants received intravitreal aflibercept 2.0 mg, repackaged (compounded) bevacizumab 1.25 mg, or ranibizumab 0.3 mg given up to every 4 weeks using defined retreatment criteria. Mean time in range was calculated using a BCVA letter score threshold of ≥69 (20/40 or better; minimum driving requirement in many regions), with sensitivity analyses using BCVA thresholds from 100 to 0 (20/10 to 20/800) in 1-letter increments.

RESULTS

Time in range was defined as either the absolute or relative duration above a predefined BCVA threshold, measured in weeks or as a percentage of time, respectively. Using a BCVA letter score threshold of ≥69 (20/40 or better), the least squares mean time in range (adjusted for baseline BCVA) in Year 1 was 41.2 weeks with intravitreal aflibercept, 4.0 weeks longer (95% CI: 1.7, 6.3; p = 0.002) than bevacizumab and 3.6 weeks longer (1.3, 5.9; p = 0.004) than ranibizumab. Overall, mean time in range was numerically longer for intravitreal aflibercept for all BCVA letter score thresholds between 92 and 30 (20/20 to 20/250). In the Day 365-728 analysis, time in range was 3.9 (1.3, 6.5) and 2.4 (0.0, 4.9) weeks longer with intravitreal aflibercept vs bevacizumab and vs ranibizumab (p = 0.011 and 0.106), respectively.

CONCLUSION

BCVA time in range may represent another way to describe visual outcomes and potential impact on vision-related functions over time for patients with DMO and provide a better understanding, for physicians and patients, of the consistency of treatment efficacy.

Contribution of common and rare variants to Asian neovascular age-related macular degeneration subtypes

Neovascular age-related macular degeneration (nAMD), along with its clinical subtype known as polypoidal choroidal vasculopathy (PCV), are among the leading causes of vision loss in elderly Asians. In a genome-wide association study (GWAS) comprising 3,128 nAMD (1,555 PCV and 1,573 typical nAMD), and 5,493 controls of East Asian ancestry, we identify twelve loci, of which four are novel ([Formula: see text]). Substantial genetic sharing between PCV and typical nAMD is noted (rg = 0.666), whereas collagen extracellular matrix and fibrosis-related pathways are more pronounced for PCV. Whole-exome sequencing in 259 PCV patients revealed functional rare variants burden in collagen type I alpha 1 chain gene (COL1A1; [Formula: see text]) and potential enrichment of functional rare mutations at AMD-associated loci. At the GATA binding protein 5 (GATA5) locus, the most significant GWAS novel loci, the expressions of genes including laminin subunit alpha 5 (Lama5), mitochondrial ribosome associated GTPase 2 (Mtg2), and collagen type IX alpha 3 chain (Col9A3), are significantly induced during retinal angiogenesis and subretinal fibrosis in murine models. Furthermore, retinoic acid increased the expression of LAMA5 and MTG2 in vitro. Taken together, our data provide insights into the genetic basis of AMD pathogenesis in the Asian population.

Potential for Treatment Interval Extension in Eyes with nAMD Disease Activity Post Loading Phase in HAWK and HARRIER

INTRODUCTION

The HAWK and HARRIER studies evaluated the efficacy and safety of brolucizumab versus aflibercept in treatment-naïve eyes with neovascular age-related macular degeneration. Based on the study design, brolucizumab-treated eyes adjusted to a q8w regimen because the presence of disease activity (DA) at the end of the matched loading phase (Week 16) could not subsequently extend to a q12w interval. The aim of this post hoc analysis was to assess subsequent DA in this subgroup to determine the potential for interval extensions during the first year of treatment.

METHODS

Pooled data from the brolucizumab 6 mg arms and aflibercept arms of HAWK and HARRIER were included. Presence of DA was determined by the masked investigator based on their assessment of functional and anatomical parameters measured by optical coherence tomography. DA was compared at DA assessments, conducted at Weeks 16, 20, 32, and 44; fluid was also assessed at the primary analysis at Week 48.

RESULTS

Fewer brolucizumab- (22.8%) than aflibercept-treated (32.2%) eyes had DA at the first DA assessment at Week 16. In eyes with investigator-identified DA at Week 16, BCVA change from baseline to Week 96 was comparable between treatment arms. Fewer brolucizumab- than aflibercept-treated eyes had DA at each subsequent DA assessment in Year 1: 31.8% vs 39.1% (Week 20), 27.3% vs 43.5% (Week 32), and 17.3% vs 31.2% (Week 44). Fewer eyes treated with brolucizumab than aflibercept had intraretinal and/or subretinal fluid: 35.3% vs 43.5% (Week 20), 55.8% vs 69.6% (Week 32), 30.0% vs 43.1% (Week 44), and 48.6% vs 68.6% (Week 48).

CONCLUSION

These findings indicate that, in eyes that still had DA 8 weeks after the final dose of loading phase, brolucizumab-treated eyes had improved fluid resolution and higher potential for treatment interval extension than aflibercept-treated eyes during the first year of treatment.

Ten-Year Incidence of Fibrosis and Risk Factors for Its Development in Neovascular Age-Related Macular Degeneration

PURPOSE

To report the incidence and risk factors for fibrosis at 10 years in a large cohort of persons with neovascular age-related macular degeneration (nAMD).

DESIGN

Retrospective, multicenter, cohort study.

METHODS

We included 225 naive nAMD eyes that underwent intravitreal anti-vascular endothelial growth factor treatment over 10 years of follow-up at two Italian referral centers. Demographic and clinical data were reviewed at baseline and on an annual basis. Onset of fibrosis was defined by clinically assessing photographs, fundus descriptions, or fluorescein angiograms. Optical coherence tomography (OCT) scans of fibrosis were inspected by an external reading center and graded as subretinal pigment epithelium (RPE), mixed, or subretinal.

RESULTS

The mean age at baseline was of 72.1 ± 6.9 years. The incidence rate of fibrosis was estimated to be 8.9 per 100 person-years, with a cumulative incidence of 62.7% at 10 years. Fibrotic lesions were sub-RPE in 46.1%, mixed in 29.8%, and subretinal in 22.7%. Independent factors associated with fibrosis included the following: larger central subfield thickness variation (P < .001), submacular hemorrhages (P = .008), higher number of injections (P = .01), and worse baseline visual acuity (VA) (P = .03). Type 2 macular neovascularization was significantly associated with mixed and subretinal fibrosis. VA significantly declined over 10 years (-16.4 Early Treatment Diabetic Retinopathy Study [ETDRS] letters), particularly in eyes with mixed and subretinal fibrosis (P < .001).

CONCLUSIONS

We identified a 62.7% cumulative incidence of fibrosis in a large nAMD cohort at 10 years. Fibrosis was more common with frequent reactivations and lower baseline VA; its onset had a significant impact on final VA. This supports the hypothesis that nAMD patients should be promptly treated with proactive regimens.

Single-cell transcriptomics reveals maturation of transplanted stem cell-derived retinal pigment epithelial cells toward native state

Transplantation of stem cell-derived retinal pigment epithelial (RPE) cells is considered a viable therapeutic option for age-related macular degeneration (AMD). Several landmark Phase I/II clinical trials have demonstrated safety and tolerability of RPE transplants in AMD patients, albeit with limited efficacy. Currently, there is limited understanding of how the recipient retina regulates the survival, maturation, and fate specification of transplanted RPE cells. To address this, we transplanted stem cell-derived RPE into the subretinal space of immunocompetent rabbits for 1 mo and conducted single-cell RNA sequencing analyses on the explanted RPE monolayers, compared to their age-matched in vitro counterparts. We observed an unequivocal retention of RPE identity, and a trajectory-inferred survival of all in vitro RPE populations after transplantation. Furthermore, there was a unidirectional maturation toward the native adult human RPE state in all transplanted RPE, regardless of stem cell resource. Gene regulatory network analysis suggests that tripartite transcription factors (FOS, JUND, and MAFF) may be specifically activated in posttransplanted RPE cells, to regulate canonical RPE signature gene expression crucial for supporting host photoreceptor function, and to regulate prosurvival genes required for transplanted RPE's adaptation to the host subretinal microenvironment. These findings shed insights into the transcriptional landscape of RPE cells after subretinal transplantation, with important implications for cell-based therapy for AMD.

Characterizing the genotypic spectrum of retinitis pigmentosa in East Asian populations: a systematic review

BACKGROUND

Ongoing trials for retinitis pigmentosa (RP) are genotype-specific, with most trials conducted on European cohorts. Due to genetic differences across diverse ancestries and populations, these therapies may not be efficacious in East Asians.

MATERIALS AND METHODS

A literature search was conducted from 1966 to September 2022 for cohort studies on East Asian populations reporting on non-syndromic RP genotypes and variants. Population-weighted prevalence was used to determine the genotypes and individual variants across the entire cohort. The carrier prevalence of common variants was compared against those in Europe.

RESULTS

A total of 12 articles describing 2,932 clinically diagnosed East Asian RP probands were included. We identified 876 variants across 54 genes. The most common genotypes included USH2A, EYS, RPGR, ABCA4, PRPF31, RHO, RP1, RP2, PDE6B and SNRNP200, with USH2A as the most common (17.1%). Overall, 60.5% of probands with clinically relevant variants were found to have one of the genotypes above, with 543/876 (62.0%) of the variants occurring in these genes. The most frequently reported variant was USH2A missense variant c.2802T>G/p.C934W (4.9%). Carrier prevalence of these variants was significantly different (p < 0.0001) than in Europe.

CONCLUSIONS

USH2A was the most commonly affected RP gene in this East Asian cohort, although sub-population analysis revealed distinct genotype prevalence patterns. While the genotypes are similar between East Asia and European cohorts, variants are specific to East Asia. The identification of several prevalent variants in USH2A and EYS provides an opportunity for the development of therapeutics that are relevant for East Asia patients.

Polypoidal Choroidal Vasculopathy: Updates on Risk Factors, Diagnosis, and Treatments

There have been recent advances in basic research and clinical studies in polypoidal choroidal vasculopathy (PCV). A recent, large-scale, population-based study found systemic factors, such as male gender and smoking, were associated with PCV, and a recent systematic review reported plasma C-reactive protein, a systemic biomarker, was associated with PCV. Growing evidence points to an association between pachydrusen, recently proposed extracellular deposits associated with the thick choroid, and the risk of development of PCV. Many recent studies on diagnosis of PCV have focused on applying criteria from noninvasive multimodal retinal imaging without requirement of indocyanine green angiography. There have been attempts to develop deep learning models, a recent subset of artificial intelligence, for detecting PCV from different types of retinal imaging modality. Some of these deep learning models were found to have high performance when they were trained and tested on color retinal images with corresponding images from optical coherence tomography. The treatment of PCV is either a combination therapy using verteporfin photodynamic therapy and anti-vascular endothelial growth factor (VEGF), or anti-VEGF monotherapy, often used with a treat-and-extend regimen. New anti-VEGF agents may provide more durable treatment with similar efficacy, compared with existing anti-VEGF agents. It is not known if they can induce greater closure of polypoidal lesions, in which case, combination therapy may still be a mainstay. Recent evidence supports long-term follow-up of patients with PCV after treatment for early detection of recurrence, particularly in patients with incomplete closure of polypoidal lesions.

Six-year incidence of age-related macular degeneration and correlation to OCT-derived drusen volume measurements in a Chinese population

AIMS

To report the 6-year incidence of optical coherence tomography (OCT)-derived age-related changes in drusen volume and related systemic and ocular associations.

METHODS

Chinese adults aged 40 years and older were assessed at baseline and 6 years with colour fundus photography (CFP) and spectral domain (SD) OCT. CFPs were graded for age-related macular degeneration (AMD) features and drusen volume was generated using commercially available automated software.

RESULTS

A total of 4172 eyes of 2580 participants (mean age 58.12±9.03 years; 51.12% women) had baseline and 6-year follow-up CFP for grading, of these, 2130 eyes of 1305 participants had gradable SD-OCT images, available for analysis. Based on CFP grading, 136 (3.39%) participants developed incident early AMD and 10 (0.25%) late AMD. Concurrently, retinal pigment epithelial-Bruch's membrane (RPE-BrC) volumes decreased, remained stable and increased in 6.8%, 78.5% and 14.7%, respectively, over 6 years. In eyes where RPE-BrC volumes were >0 mm³ at baseline, this was associated with two-fold higher prevalence rate of any AMD at baseline (p<0.001). Multivariable analysis showed that when compared with eyes where RPE-BrC volume was unchanged, volume decrease was significantly associated with older age (OR=1.30; p<0.001), smoking (OR=2.21; p=0.001) and chronic kidney disease (OR=3.4, p=0.008), while increase was associated with older age (OR=1.36; p<0.001) and hypertension (OR=1.43; p=0.016).

CONCLUSION

AMD incidence detected at 6 years on CFP and correlated OCT-derived drusen volume measurement change is low. Older age and some systemic risk factors are associated with drusen volume change, and our data provide new insights into relationship between systemic risk factors and outer retinal morphology in Asian eyes.

Microperimetry in Retinal Diseases

Retinal microperimetry (MP) is a procedure that assesses the retinal sensitivity while the fundus is directly observed, and an eye tracker system is active to compensate for involuntary eye movements during testing. With this system, the sensitivity of a small locus can be accurately determined, and it has become an established ophthalmic test for retinal specialists. Macular diseases are characterized by chorioretinal changes; therefore, the condition of the retina and choroid requires careful and detailed evaluations to perform effective therapy. Age-related macular degeneration is a representative retinal disease in which the macular function has been evaluated by the visual acuity throughout the course of the disease process. However, the visual acuity represents the physiological function of only the central fovea, and the function of the surrounding macular area has not been sufficiently evaluated throughout the different stages of the macula disease process. The new technique of MP can compensate for such limitations by being able to test the same sites of the macular area repeatedly. This is especially useful in the recent management of age-related macular degeneration or diabetic macular edema during anti-vascular endothelial growth factor treatments because MP can assess the effectiveness of the treatment. MP examinations are also valuable in diagnosing Stargardt disease as they can detect visual impairments before any abnormalities are found in the retinal images. The visual function needs to be carefully assessed along with morphologic observations by optical coherence tomography. In addition, the assessment of retinal sensitivity is useful in the presurgical or postsurgical evaluations.

Review on the Safety and Efficacy of Brolucizumab for Neovascular Age-Related Macular Degeneration From Major Studies and Real-World Data

Frequent antivascular endothelial growth factor injections in neovascular age-related macular degeneration (nAMD) often lead to poor compliance and suboptimal outcomes. A longer-acting agent has been a pressing unmet need until recently. Brolucizumab, an antivascular endothelial growth factor agent, is a single-chain antibody fragment approved by the US Food and Drug Administration (FDA) on October 8, 2019, for treating nAMD. It delivers more molecules at equivalent volumes of aflibercept, thus achieving a longer-lasting effect. We reviewed literature published in English between January 2016 and October 2022 from MEDLINE, PubMed, Cochrane database, Embase, and Google scholar using the keywords: "Brolucizumab, real-world data, intraocular inflammation (IOI), safety, and efficacy". Brolucizumab showed reduced injection frequency, better anatomic outcomes, and noninferior vision gains compared with aflibercept in HAWK and HARRIER studies. However, post hoc studies on brolucizumab revealed a higher-than-expected incidence of IOI, leading to the early termination of 3 studies: MERLIN, RAPTOR, and RAVEN for nAMD, branch retinal vein occlusion, and central retinal vein occlusion, respectively. Contrastingly real-world data showed encouraging outcomes in terms of fewer IOI cases. The subsequent amendment of the treatment protocol resulted in reduced IOI. Thereafter US FDA approved its use in diabetic macular edema on June 1, 2022. Based on major studies and real-world data, this review shows that brolucizumab is effective for treating naive and refractory nAMD. The risk of IOI is acceptable and manageable, but proper preinjection screening and high-vigilance care of IOI are needed. More studies are warranted to evaluate further the incidence, best prevention, and treatment measures for IOI.

Analysis of the pachychoroid phenotype in an Asian population: methodology and baseline study population characteristics

AIM

To describe the clinical characteristics in a cohort of patients with the pachychoroid phenotype and to evaluate the association of ocular and systemic factors with type of complications observed.

METHODS

We report baseline findings from a prospective observational study which recruited subjects with subfoveal choroidal thickness (SFCT) of ≥300 µm on spectral-domain optical coherence tomography (OCT). Multimodal imaging was used to classify eyes as uncomplicated pachychoroid (UP) or pachychoroid disease with pachychoroid pigment epitheliopathy (PPE), central serous chorioretinopathy (CSC) or pachychoroid neovasculopathy (PNV) subtypes.

RESULTS

Among 181 eyes of 109 participants (mean age 60.6 years, 33 (30.3%) female, 95 (7.2%) Chinese), 38 eyes (21.0%) had UP. Of 143 eyes (79.0%) with pachychoroid disease, 82 (45.3%), 41 (22.7%) and 20 (11.0%) had PPE, CSC and PNV, respectively. Addition of autofluorescence and OCT angiography to structural OCT led to reclassification of 31 eyes to a more severe category. Systemic and ocular factors evaluated, including SFCT, were not associated with disease severity. Comparison of PPE, CSC and PNV eyes showed no significant difference in OCT features of retinal pigment epithelial (RPE) dysfunction, but disruption of the ellipsoid zone (PPE 30.5% vs CSC 70.7% vs PNV 60%, p<0.001) and thinning of inner nuclear/inner plexiform layers (PPE 7.3% vs CSC 36.6% vs PNV 35%, p<0.001) were more frequent in CSC and PNV eyes.

CONCLUSIONS

These cross-sectional associations suggest pachychoroid disease manifestations may reflect progressive decompensation from the choroid to the RPE then retinal layers. Planned follow-up of this cohort will be beneficial in clarifying the natural history of the pachychoroid phenotype.

Characterization of the Structural and Functional Alteration in Eyes with Diabetic Macular Ischemia

OBJECTIVE

To investigate the relative effect of disorganization of the retinal inner layers (DRIL) and ellipsoid zone (EZ) loss on visual function in diabetic macular ischemia (DMI).

DESIGN

Prospective cross-sectional observational study.

PARTICIPANTS

Patients with stable treated proliferative diabetic retinopathy (PDR) without center-involved diabetic macular edema were recruited at the Moorfields Eye Hospital from December 2019 to November 2021. The main inclusion criteria were best-corrected visual acuity (BCVA) of ≥ 40 ETDRS letters (Snellen equivalent 20/160) with OCT angiography (OCTA) evidence of DMI in ≥ 1 eye.

METHODS

Each eligible eye of the recruited patients was assessed for BCVA, OCT, and OCTA metrics. The prespecified OCT parameters were DRIL and subfoveal EZ loss. Generalized estimating equations were used.

MAIN OUTCOMES MEASURES

The frequency of DRIL and EZ loss, their relative contributions to vision loss, and their associations with microvascular alterations were evaluated.

RESULTS

A total of 125 eyes of 86 patients with PDR were enrolled; 104 (83%) eyes had a BCVA of ≥ 70 letters. Disorganization of the retinal inner layers was more prevalent than EZ loss (46% [58 eyes] vs. 19% [24 eyes]). On average, the presence of DRIL had a more pronounced impact on vision, retinal thickness, and microvascular parameters than EZ loss. After multivariable adjustment, the odds of coexisting DRIL increased by 12% with every letter decrease in BCVA; however, there was no statistically significant association of subfoveal EZ loss with BCVA. In eyes with DRIL in the absence of EZ loss, the BCVA declined significantly by 6.67 letters compared with eyes with no DRIL nor EZ loss (95% confidence interval [CI], -9.92 to -3.41; P < 0.001). However, if DRIL and EZ loss coexisted, the resultant BCVA was 13.22 letters less than eyes without these structural abnormalities (95% CI, -18.85 to -7.59; P < 0.001).

CONCLUSIONS

In patients with DMI with a Snellen visual acuity of 20/160 or better, eyes with DRIL were associated with more visual function loss and retinal blood circulation alterations than those with subfoveal EZ loss only.

Joint multimodal deep learning-based automatic segmentation of ICGA and OCT images for assessment of PCV biomarkers

Purpose

To develop a fully-automatic hybrid algorithm to jointly segment and quantify biomarkers of polypoidal choroidal vasculopathy (PCV) on indocyanine green angiography (ICGA) and spectral domain-OCT (SD-OCT) images.

Design

Evaluation of diagnostic test or technology.

Participants

Seventy-two participants with PCV enrolled in clinical studies at Singapore National Eye Center.

Methods

The dataset consisted of 2-dimensional (2-D) ICGA and 3-dimensional (3-D) SD-OCT images which were spatially registered and manually segmented by clinicians. A deep learning-based hybrid algorithm called PCV-Net was developed for automatic joint segmentation of biomarkers. The PCV-Net consisted of a 2-D segmentation branch for ICGA and 3-D segmentation branch for SD-OCT. We developed fusion attention modules to connect the 2-D and 3-D branches for effective use of the spatial correspondence between the imaging modalities by sharing learned features. We also used self-supervised pretraining and ensembling to further enhance the performance of the algorithm without the need for additional datasets. We compared the proposed PCV-Net to several alternative model variants.

Main Outcome Measures

The PCV-Net was evaluated based on the Dice similarity coefficient (DSC) of the segmentations and the Pearson's correlation and absolute difference of the clinical measurements obtained from the segmentations. Manual grading was used as the gold standard.

Results

The PCV-Net showed good performance compared to manual grading and alternative model variants based on both quantitative and qualitative analyses. Compared to the baseline variant, PCV-Net improved the DSC by 0.04 to 0.43 across the different biomarkers, increased the correlations, and decreased the absolute differences of clinical measurements of interest. Specifically, the largest average (mean ± standard error) DSC improvement was for intraretinal fluid, from 0.02 ± 0.00 (baseline variant) to 0.45 ± 0.06 (PCV-Net). In general, improving trends were observed across the model variants as more technical specifications were added, demonstrating the importance of each aspect of the proposed method.

Conclusion

The PCV-Net has the potential to aid clinicians in disease assessment and research to improve clinical understanding and management of PCV.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Genetic Variability of Complement Factor H Has Ethnicity-Specific Associations With Choroidal Thickness

Purpose

To identify genetic alleles associated with differences in choroidal thickness (CT) in a population-based multiethnic Asian cohort.

Methods

A population-based multiethnic Asian cohort without retinal pathology was subjected to spectral-domain OCT (SD-OCT) and genotyping of risk alleles in CFH, VIPR2, ARMS2, and CETP. Subfoveal choroidal thickness (SFCT) values were assessed from SD-OCT, and associations with the risk alleles were determined for each cohort.

Results

A total of 1045 healthy Asian individuals (550 Chinese, 147 Indians, 348 Malays) were prospectively enrolled in the study. Several CFH alleles (rs800292, rs1061170, and rs1329428) were associated with increased SFCT in Indians (+18.7 to +31.7 µm; P = 0.001-0.038) and marginally associated with decreased SFCT in Malays (-12.7 to -20.6 µm; P = 0.014-0.022). Haplotype analysis of CFH revealed variable associations with SFCT among races, with the H6 haplotype being associated with a 29.08-µm reduction in SFCT in the Chinese cohort (P = 0.02) but a 35.2-µm increase in SFCT in the Indian cohort (P < 0.001). Finally, subfield analysis of the Chinese cohort identified associations between the CFH risk allele rs1061170 and reduced CT in the nasal and superior sectors (-20.2 to -25.8 µm; P = 0.003-0.027).

Conclusions

CFH variants are variably associated with CT among Asian ethnic groups. This has broad implications for the pathogenesis of common diseases such as age-related macular degeneration and central serous choroidopathy, the pathogenesis of which is associated with CT.

Review of Fibrosis in Neovascular Age-Related Macular Degeneration

PURPOSE

To report the diagnosis and definitions, epidemiology, risk factors, and visual outcomes of fibrosis in neovascular age-related macular degeneration (nAMD).

DESIGN

Systematic review and meta-analysis.

METHODS

The review was performed using the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Observational studies and randomized controlled trials were included.

RESULTS

Identification of fibrosis is challenging. Optical coherence tomography angiography and polarization-sensitive optical coherence tomography represent novel options in multimodal imaging. The prevalence of fibrosis at baseline, 12, 24, and 60 months was 13%, 32%, 36%, and 56%, respectively. Approximately 60% of the fibrosis burden in nAMD at 5 years was present in the first year of treatment. Fibrosis development was highest in the first 12 months and slowed down over time. The risk factors of fibrosis included classic choroidal neovascularization (CNV), intra-retinal fluid, hemorrhage, hyperreflective material, CNV lesion size, and retinal thickness. Sub-retinal fluid and pigment epithelial detachment may be protective. Treatment-associated factors included disease activity and time to diagnosis. At baseline, the best corrected visual acuity in eyes with fibrosis was poorer than in eyes without fibrosis (-18.50 letters); this difference became larger at 12 months despite treatment (-26.86 letters).

CONCLUSIONS

There is a need to identify effective treatment strategies for fibrosis and to closely monitor at-risk patients. More studies involving multimodal imaging are required to clarify the definitions and grading criteria for fibrosis.

Efficacy, safety, and treatment burden of treat-and-extend versus alternative anti-VEGF regimens for nAMD: a systematic review and meta-analysis

This study aimed to compare efficacy and treatment burden of treat-and-extend (T&E) anti-VEGF against fixed and pro re nata (PRN) regimens for neovascular age-related macular degeneration (nAMD). MEDLINE, CENTRAL, and EMBASE were searched. Randomized-controlled trials and observational studies comparing T&E to PRN or fixed dosing for treatment-naïve AMD patients were included. Mean difference (MD) for visual acuity (VA) and number of injections are presented. Risk of bias was assessed according to Cochrane guidelines. Methodology was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). VA improvement was similar with T&E and fixed dosing at one (MD -0.08 letters, p = 0.95) and two years (MD 0.58 letters, p = 0.62). In contrast, VA improvements were significantly greater for T&E when compared against a PRN regimen at one (MD 3.95 letters, p < 0.0001) and two years (MD 4.08 letters, p < 0.001). Significantly fewer ranibizumab injections were administered in the T&E arm at one (MD -2.42 injections, p < 0.0001) and two years (MD -6.06 injections, p < 0.00001) relative to fixed dosing. Fewer aflibercept injections were likewise administered to patients on a T&E regimen versus fixed dosing at one year (MD -0.78 injections, p < 0.0001). Low-certainty evidence from the present synthesis implies that T&E preserves VA similar to fixed schedules with significantly fewer injections at one and two years. Also, patients with T&E dosing achieved better VA outcomes than those on PRN regimen but T&E dosing was associated with more injections.

CHOROIDAL VASCULAR ALTERATIONS IN AGE-RELATED MACULAR DEGENERATION AND POLYPOIDAL CHOROIDAL VASCULOPATHY

PURPOSE

To evaluate morphologic alterations in choroidal veins in eyes with typical neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV).

METHODS

A retrospective review of baseline indocyanine green angiography in eyes with typical nAMD and PCV. We evaluated Haller layer veins in the early-phase indocyanine green angiography (before 2 minutes) for 1) macular anastomosis, 2) dilated Haller veins, and 3) focal variation in vessel caliber by at least 50% from the narrowest to largest diameters.

RESULTS

We included 70 patients with gradable indocyanine green angiography for the prespecified features in the study eye (36 typical nAMD and 34 PCV) and 59 fellow eyes. The median subfoveal choroidal thickness was 167 µm versus 219 µm, P = 0.08, in the presenting eyes in typical nAMD and PCV, respectively. Macular anastomosis was common in both typical nAMD and PCV (presenting eyes 58.3% vs. 58.8%. P = 0.97; fellow eyes 65.5% vs. 63.3%, P = 0.86). Dilated Haller veins were numerically less common in typical nAMD than PCV (presenting eyes 52.8% vs. 67.6%, P = 0.21; fellow eyes 65.5% vs. 70.0%, P = 0.71), while vascular caliber variation was numerically more common in typical nAMD than PCV (presenting eyes 72.2% vs. 63.8%, P = 0.45; fellow eyes 69.0% vs. 56.7%, P = 0.33). The presence of all three features was more common in the presenting eyes with PCV compared with typical nAMD (35.3% vs. 13.9%, P = 0.03). In a multivariable analysis, every increase of 100 µm of CT conferred a 2.75 risk of having all three features present.

CONCLUSION

Choroidal vascular remodeling is common in both tAMD and PCV but may be driven by different stimuli.

Geographic Atrophy Phenotypes in Subjects of Different Ethnicity: Asia-Pacific Ocular Imaging Society Work Group Report 3

OBJECTIVE

To characterize geographic atrophy (GA) and evaluate differences between Asians and non-Asians.

DESIGN

Multicenter, retrospective case series.

PARTICIPANTS

Subjects aged ≥ 50 years with GA secondary to age-related macular degeneration in the absence of neovascularization in the study eye and follow-up of ≥ 2 years.

METHODS

The GA lesion characterized at baseline and last follow-up based on multimodal imaging (fundus autofluorescence [FAF], near infrared [NIR], and spectral domain-OCT). Patients were grouped as either Asian or non-Asian.

MAIN OUTCOME MEASURES

Comparison of (1) phenotypes of GA lesions (size, foveal involvement, number of foci, drusen background, and choroid background) and (2) growth rates of GA.

RESULTS

A total of 144 patients (169 eyes) with distribution of 50.9% Asians and 49.1% non-Asians. The age and sex were similar between Asians and non-Asians (Asians: mean age, 77.2 ± 10.1 years, 47.9% female; non-Asians: mean age, 79.7 ± 8.4 years, 58.7% female). Asians exhibited thicker choroids (167 ± 74 versus [vs.] 134 ± 56 μm; P < 0.01) and lower prevalence of drusen (40.7% vs. 66.3%; P < 0.01). At baseline, the GA area was smaller in Asians vs. non-Asians (NIR, 3.7 ± 4.6 vs. 6.3 ± 6.8 mm²; P = 0.01: FAF, 2.4 ± 3.4 vs. 8.4 ± 9.6 mm²; P < 0.01). Asians had fewer GA foci (1.7 ± 1.3 vs. 2.7 ± 2.2; P < 0.01) compared to non-Asians. The proportion with diffused or banded FAF junctional zone pattern was similar between Asians and non-Asians (44.2% vs. 60.2%; P = 0.20). Asians had a slower GA lesion growth rate than non-Asians (NIR, 0.7 vs. 1.9 mm²/year; P < 0.01: FAF, 0.3 vs. 2.0 mm²/year; P < 0.01: NIR, 0.4 vs. 0.9 mm/year; P < 0.001 square root transformed: FAF, 0.3 vs. 1.0 mm/year; P < 0.001 square root transformed). The factors associated with GA lesion growth rate are (from the highest effect size) ethnicity, junctional zone FAF pattern, baseline GA area, and number of GA foci. Higher GA lesion growth rate was observed in both Asian and non-Asian subgroups, with drusen or lesion size and FAF patterns meeting inclusion criteria of recent therapeutic trials, but growth rate remained significantly slower in Asians. Eyes with baseline lesion ≥ 5 mm² showed the highest growth rate, and the difference between ethnicities was no longer significant (2.6 vs. 3.3 mm²/year; P = 0.09).

CONCLUSIONS

There are differences in GA lesion phenotype, associated features, and growth rate between Asians and non-Asian subjects.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Real-world cost-effectiveness of anti-VEGF monotherapy and combination therapy for the treatment of polypoidal choroidal vasculopathy

OBJECTIVES

For patients with polypoidal choroidal vasculopathy (PCV), intravitreal anti-vascular endothelial growth factor (anti-VEGF) combination therapy has been shown to be cost-saving relative to monotherapy in a clinical trial setting. However, whether this also applies to real-world settings is unclear. We aim to compare the real-world functional outcomes and cost-effectiveness of intravitreal anti-VEGF combination therapy relative to monotherapy, to investigate whether combination therapy is truly cost-saving.

METHODS

We used a Markov model to simulate a hypothetical cohort of PCV patients treated at Singapore National Eye Centre. Model parameters were informed by coarsened exact matched estimates of a two-year retrospective study of patients who initiated treatment in 2015. Treatment options included intravitreal aflibercept, bevacizumab, or ranibizumab, as monotherapy or in combination with full-fluence verteporfin photodynamic therapy.

RESULTS

The two-year logMAR letters gains were significant for combination therapy ( + 10.6, P = 0.006) but not monotherapy (-2.2, P = 0.459). Over 20 years, a PCV patient would cost the health system SGD 48,790 under monotherapy and SGD 61,020 under combination therapy. Quality-adjusted life-years (QALYs) were estimated to be 7.41 for monotherapy and 7.80 for combination therapy. The incremental cost-effectiveness ratio of combination therapy was SGD 31,460/QALY, which is less than the common willingness-to-pay threshold of per capita gross domestic product of Singapore (SGD 88,990/QALY). Sensitivity analysis showed that combination therapy remained incrementally cost-effective, but not cost-saving.

CONCLUSIONS

Our study shows that combination therapy is good value for money but is likely to increase costs when applied in real-world settings.

Clinical impact of the worldwide shortage of verteporfin (Visudyne®) on ophthalmic care

INTRODUCTION

Since July 2021, a worldwide shortage of verteporfin (Visudyne®) occurred: an essential medicine required for photodynamic therapy (PDT). PDT with verteporfin has a broad range of indications in ophthalmology, including chronic central serous chorioretinopathy, polypoidal choroidal vasculopathy and choroidal haemangioma. For these disorders, PDT is either the first-choice treatment or regarded as a major treatment option.

MATERIALS AND METHODS

A questionnaire was sent to key opinion leaders in the field of medical retina throughout the world, to assess the role of PDT in their country and the effects of the shortage of verteporfin. In addition, information on the application of alternative treatments during shortage of verteporfin was obtained, to further assess the impact of the shortage.

RESULTS

Our questionnaire indicated that the shortage of verteporfin had a major impact on ophthalmic care worldwide and was regarded to be a serious problem by most of our respondents. However, even though there is ample evidence to support the use of PDT in several chorioretinal diseases, we found notable differences in its use in normal patient care throughout the world. Various alternative management strategies were noted during the verteporfin shortage, including lowering the dose of verteporfin per patient, the use of alternative treatment strategies and the use of a centralized system for allocating the remaining ampoules of verteporfin in some countries.

CONCLUSION

The shortage of verteporfin has had a large effect on the care of ophthalmic patients across the world and may have resulted in significant and irreversible vision loss. Mitigation strategies should be developed in consultation with all stakeholders to avoid future medication shortages of verteporfin and other unique ophthalmic medications. These strategies may include mandatory stock keeping, compulsory licensing to an alternative manufacturer or incentivizing the development of competition, for example through novel public-private partnerships.

Normative Data and Associations of OCT Angiography Measurements of the Macula: The Singapore Malay Eye Study

OBJECTIVE

To describe the normative quantitative parameters of the macular retinal vasculature, as well as their systemic and ocular associations using OCT angiography (OCTA).

DESIGN

Population-based, cross-sectional study.

SUBJECTS

Adults aged > 50 years were recruited from the third examination of the population-based Singapore Malay Eye Study.

METHODS

All participants underwent a standardized comprehensive examination and spectral-domain OCTA (Optovue) of the macula. OCT angiography scans that revealed pre-existing retinal disease, revealed macular pathology, and had poor quality were excluded.

MAIN OUTCOME MEASURES

The normative quantitative vessel densities of the superficial layer, deep layer, and foveal avascular zone (FAZ) were evaluated. Ocular and systemic associations with macular retinal vasculature parameters were also evaluated in a multivariable analysis using linear regression models with generalized estimating equation models.

RESULTS

We included 1184 scans (1184 eyes) of 749 participants. The mean macular superficial vessel density (SVD) and deep vessel density (DVD) were 45.1 ± 4.2% (95% confidence interval [CI], 37.8%-51.4%) and 44.4 ± 5.2% (95% CI, 36.9%-53.2%), respectively. The mean SVD and DVD were highest in the superior quadrant (48.7 ± 5.9%) and nasal quadrant (52.7 ± 4.6%), respectively. The mean FAZ area and perimeter were 0.32 ± 0.11 mm² (95% CI, 0.17-0.51 mm) and 2.14 ± 0.38 mm (95% CI, 1.54-2.75 mm), respectively. In the multivariable regression analysis, female sex was associated with higher SVD (β = 1.25, P ≤ 0.001) and DVD (β = 0.75, P = 0.021). Older age (β = -0.67, P < 0.001) was associated with lower SVD, whereas longer axial length (β = -0.42, P = 0.003) was associated with lower DVD. Female sex, shorter axial length, and worse best-corrected distance visual acuity were associated with a larger FAZ area. No association of a range of systemic parameters with vessel density was found.

CONCLUSIONS

This study provided normative macular vasculature parameters in an adult Asian population, which may serve as reference values for quantitative interpretation of OCTA data in normal and disease states.

Single-Cell Transcriptome of Wet AMD Patient-Derived Endothelial Cells in Angiogenic Sprouting

Age-related macular degeneration (AMD) is a global leading cause of visual impairment in older populations. ‘Wet’ AMD, the most common subtype of this disease, occurs when pathological angiogenesis infiltrates the subretinal space (choroidal neovascularization), causing hemorrhage and retinal damage. Gold standard anti-vascular endothelial growth factor (VEGF) treatment is an effective therapy, but the long-term prevention of visual decline has not been as successful. This warrants the need to elucidate potential VEGF-independent pathways. We generated blood out-growth endothelial cells (BOECs) from wet AMD and normal control subjects, then induced angiogenic sprouting of BOECs using a fibrin gel bead assay. To deconvolute endothelial heterogeneity, we performed single-cell transcriptomic analysis on the sprouting BOECs, revealing a spectrum of cell states. Our wet AMD BOECs share common pathways with choroidal neovascularization such as extracellular matrix remodeling that promoted proangiogenic phenotype, and our ‘activated’ BOEC subpopulation demonstrated proinflammatory hallmarks, resembling the tip-like cells in vivo. We uncovered new molecular insights that pathological angiogenesis in wet AMD BOECs could also be driven by interleukin signaling and amino acid metabolism. A web-based visualization of the sprouting BOEC single-cell transcriptome has been created to facilitate further discovery research.

Relationship between Pachychoroid and Polypoidal Choroidal Vasculopathy

Previous clinical studies have suggested that pachychoroid can induce macular neovascularization (MNV) to develop pachychoroid neovasculopathy (PNV) and that PNV can progress to polypoidal choroidal vasculopathy (PCV). Recent studies based on the pachychoroid concept are now gradually revealing the true nature of, at least some part of, PCV. However, previous studies on PNV and/or PCV have used different frameworks for the classification of PNV, PCV, and neovascular age-related macular degeneration (nAMD). These have hampered the rapid overhaul of the understanding of PCV. Some investigators have assumed that all PCV is pachychoroid-driven whereas other investigators have classified PCV into “pachychoroid PCV” and “non-pachychoroid PCV”. Furthermore, since there is no consensus as to whether PNV includes PCV, some studies have included PCV with PNV, while other studies have excluded PCV from PNV. To address these gaps, we summarize previous studies on PCV and pachychoroid. Even before the proposal of the pachychoroid concept, previous studies had suggested that PCV could be divided into two subtypes, of which one was characterized by pachychoroid features. Previous studies had also provided keys to understand relationship between PCV and PNV. We here recommend a refined conceptual framework for future studies on PNV, PCV, and nAMD. Considering the current inconsistent understanding of PCV, we should be cautious about using the term PCV until we understand the true nature of PCV.

Correlation of Optical Coherence Tomography Angiography Characteristics with Visual Function to Define Vision-Threatening Diabetic Macular Ischemia

The thresholds of macular microvasculature parameters associated with mild visual impairment in diabetic macular ischemia (DMI) patients are unclear. Therefore, this prospective observational study is aimed at demonstrating the optical coherence tomography angiography parameters that best correlate with mild visual impairment (<70 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, Snellen equivalent 20/40) in DMI. The study was completed at the Moorfields Eye Hospital from December 2019 to August 2021. A total of 123 eyes of 87 patients with stable-treated proliferative diabetic retinopathy following panretinal photocoagulation were recruited. DMI was defined as an irregular foveal avascular zone (FAZ) area ≥ 0.5 mm2 or a smaller FAZ area with parafoveal capillary dropout in at least one quadrant. The analysis showed that the whole image deep vascular complex vessel density (DVC VD) in the 3 × 3 mm area had the best discriminatory ability to identify participants with mild visual impairment at 41.9% (area under the curve = 0.77, sensitivity 94%, specificity 54%, likelihood ratio [LR] = 2.04), and the FAZ area had the greatest post-test LR = 4.21 at 0.64 mm2. The 3 × 3 mm whole image DVC VD and FAZ area cutoffs are useful for screening vision-threatening DMI, but DVC VD has low specificity.

PREVALENCE AND CHARACTERISTICS OF MULTIFOCAL CHOROIDITIS/PUNCTATE INNER CHOROIDOPATHY IN PATHOLOGIC MYOPIA EYES WITH PATCHY ATROPHY

PURPOSE

To determine the prevalence and characteristics of multifocal choroiditis/punctate inner choroidopathy (MFC/PIC) in eyes with patchy atrophy because of pathologic myopia.

METHODS

Five hundred eyes of 253 patients with patchy atrophy were examined between 2014 and 2020 at the Advanced Clinical Center for Myopia. The main outcome measures included the prevalence and characteristics of active MFC/PIC lesions diagnosed by optical coherence tomography.

RESULTS

Fifty-five of the 500 eyes (11%) diagnosed with patchy atrophy had optical coherence tomography features of active MFC/PIC lesions, such as focal elevations of the retinal pigment epithelium filled with medium hyperreflectivity material, curvilinear scars (Schlaegel lines), and/or areas of outer retinal atrophy. At the time when the MFC/PIC was diagnosed, the mean age was 57.3 ± 12.0 years, and the mean axial length was 29.2 ± 1.8 mm. Macular neovascularization was found in 45 of eyes (81.8%) with MFC/PIC versus 151 eyes without such findings (33.9%; P < 0.001). In 25 of the 55 eyes (45.5%), active MFC/PIC lesions were found before the development of the patchy atrophy. The Bruch membrane defects were colocated with these lesions.

CONCLUSION

Active MFC/PIC lesions were identified in a minority of eyes with pathologic myopia, and a subset of these lesions were observed to progress to findings indistinguishable from myopic patchy atrophy. Evidence of MFC/PIC in eyes with pathologic myopia appeared to be a risk factor for the development of macular neovascularization.

Serum Cholesterol Efflux Capacity in Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy

Purpose

To investigate serum cholesterol efflux capacity (the ability of the serum to accept cholesterol) and factors that regulate it using nuclear magnetic resonance-quantified measures of lipoprotein particle composition and size and apolipoproteins metrics in patients with age-related macular degeneration (AMD).

Design

Case-control study.

Participants

Four hundred two serum samples from 80 patients with early AMD (eAMD), and 212 patients with neovascular AMD (nAMD), including 80 with typical nAMD (tAMD) and 132 with polypoidal choroidal vasculopathy (PCV), and 110 age- and gender matched control participants.

Methods

Serum from participants showed cholesterol efflux capacity measured using in vitro cell assays and lipoprotein subfractions measured using nuclear magnetic resonance (Nightingale, Ltd). Associations between cholesterol efflux capacity (measured in percentage) and lipid subfractions were investigated in the patients and control participants.

Main Outcome Measures

Cholesterol efflux capacity and lipid subfractions in control, eAMD, and nAMD. Associations between HDL subfractions and cholesterol efflux capacity.

Results

Cholesterol efflux capacity was higher in patients with eAMD (68.0 ± 11.3% [mean ± standard deviation]) and nAMD (75.9 ± 27.7%) than in the control participants (56.9 ± 16.7%) after adjusting for age, gender, and use of lipid-lowering drug (P < 0.0001). Nuclear magnetic resonance lipidomics demonstrated that the mean diameter of HDL was larger both in eAMD (9.96 ± 0.27 mm [mean ± standard deviation]) and PCV (9.97 ± 0.23 mm) compared with that of the control participants (9.84 ± 0.24 mm; P = 0.0001 for both). Among the 28 HDL subfractions, most of the small, medium, and large HDLs, but none of the 7 extra large HDLs fractions, were associated moderately with cholesterol efflux capacity in eAMD and PCV (R = 0.149-0.277).

Conclusions

Serum cholesterol efflux capacity was increased in eAMD and PCV, but not tAMD, possibly reflecting differential underlying pathophysiologic features of lipid dysregulation in tAMD and PCV. Further studies should be directed toward investigating the diverse biological activities of HDL in AMD, including macular pigment transport, regulation of inflammation, and local cholesterol transport system.

COVID-19-Related Retinal Micro-vasculopathy - A Review of Current Evidence

PURPOSE

To evaluate the occurrence of retinal microvasculopathy in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and who developed coronavirus disease (COVID-19).

DESIGN

Systematic review and meta-analysis.

METHODS

The Pubmed and Embase databases were comprehensively searched to identify studies that reported retina vascular changes in eyes with COVID-19. Two independent reviewers selected papers and extracted data for analysis. Data of interest were extracted and analyzed in RevMan Web versions 3.3. Quality of evidence was assessed using the National Institute of Health quality assessment tool for a case-control study.

RESULTS

Thirty-one studies reporting on 1373 subjects (972 COVID-19 and 401 controls) were included. Only case-control studies were included in the pooled analysis. There was a significantly higher likelihood of retinal microvasculopathy in subjects with COVID-19 compared to controls (odds ratio [95% confidence interval], 8.86 [2.54-27.53], P < .01). Optical coherence tomography angiography (OCTA) revealed reduced vessel density and enlarged foveal avascular zone in subjects with COVID-19 compared to controls.

CONCLUSIONS

The results suggested that COVID-19-related retinal microvasculopathy is a significant ocular manifestation of COVID-19 and may herald future retinal complications. These microvascular impairments might have occurred antecedent to clinically visible changes and could be detected earlier by OCTA. These findings are significant, due to the large numbers with COVID-19, and need to be recognized by ophthalmologists as a potential long-term sequalae of the disease.

Novel volumetric imaging biomarkers for assessing disease activity in eyes with PCV

The aim of this study was to evaluate influence of baseline imaging features on visual and anatomical outcomes in eyes with PCV treated with anti-VEGF monotherapy. In this prospective study we enrolled participants with treatment-naïve PCV who followed a treat-and-extend protocol using intravitreal aflibercept (IVA) monotherapy. Baseline clinical features evaluatedincluded best corrected visual acuity (BCVA), traditional features such as lesion size, fluid-related OCT parameters and novel parameters using automated software. This included quantitative and qualitative pigment epithelium detachment (PED) parameters [height, volume]; and choroidal parameters. [choroidal thickness (CT), choroidal volume (CV) and choroidal vascularity index (CVI). We evaluated the predictive value of each parameter on visual and anatomical outcome at month 12. We additionally evaluated initial treatment response after 3 monthly injections with respect to month 12 outcomes. Fifty-two eyes from 52 participants were included in the study. The BCVA increased from 61.1 ± 13.2 to 69.6 ± 13.2 early treatment diabetic retinopathy study (ETDRS) letters (p < 0.01) and CRT reduced from 455.7 ± 182.4 µm to 272.7 ± 86.2 (p < 0.01) from baseline to month 12. The proportion of eyes with PED decreased significant from 100% at baseline to 80% at month 12 (p < 0.01). Reduction in the mean maximum height of PED (from 381.3 ± 236.3 µm to 206.8 vs ± 146.4 µm) and PED volume (from 1322 ± 853 nl to 686 ± 593 nl) (p < 0.01) was also noted from baseline to month12. Baseline features associated with better month 12 BCVA included baseline BCVA (β =  − 0.98, 95%CI − 3.38 to − 1.61, p = 0.02) and baseline CRT (β =  − 0.98, 95%CI − 1.56 to − 0.40, p = 0.04) while the disease activity at month12 was significantly associated with lower baseline CRT (366.0 ± 129.5 vs 612.0 ± 188.0 , p < 0.001), lower baseline PED height (242.0 ± 150.0 vs 542.0 ± 298.0 µm, p < 0.01), lower baseline PED volume (0.6 ± 0.3 mm³ vs 2.2 ± 1.3 mm³ vs, p < 0.01), lower proportion with marked CVH (17.9% vs 46.2%, p = 0.02) and lower mean CVI (61.8 ± 1.4 vs 63.0 ± 1.4, p < 0.02). Additionally, a larger decrease in CRT (per 100 nm) and larger PED volume reduction (per 100 nl) at month 3 from baseline were associated with greater BCVA gain and inactive disease. PED-related volumetric parameters have an additional predictive value to traditional biomarkers of disease activity in eyes with PCV undergoing anti-VEGF monotherapy. With increasingly precise quantification, PEDs can be a crucial biomarker in addition to traditional parameters and may aid in retreatment decisions.

Efficacy, durability, and safety of intravitreal faricimab up to every 16 weeks for neovascular age-related macular degeneration (TENAYA and LUCERNE): two randomised, double-masked, phase 3, non-inferiority trials

BACKGROUND

Faricimab is a bispecific antibody that acts through dual inhibition of both angiopoietin-2 and vascular endothelial growth factor A. We report primary results of two phase 3 trials evaluating intravitreal faricimab with extension up to every 16 weeks for neovascular age-related macular degeneration (nAMD).

METHODS

TENAYA and LUCERNE were randomised, double-masked, non-inferiority trials across 271 sites worldwide. Treatment-naive patients with nAMD aged 50 years or older were randomly assigned (1:1) to intravitreal faricimab 6·0 mg up to every 16 weeks, based on protocol-defined disease activity assessments at weeks 20 and 24, or aflibercept 2·0 mg every 8 weeks. Randomisation was performed through an interactive voice or web-based response system using a stratified permuted block randomisation method. Patients, investigators, those assessing outcomes, and the funder were masked to group assignments. The primary endpoint was mean change in best-corrected visual acuity (BCVA) from baseline averaged over weeks 40, 44, and 48 (prespecified non-inferiority margin of four letters), in the intention-to-treat population. Safety analyses included patients who received at least one dose of study treatment. These trials are registered with ClinicalTrials.gov (TENAYA NCT03823287 and LUCERNE NCT03823300).

FINDINGS

Across the two trials, 1329 patients were randomly assigned between Feb 19 and Nov 19, 2019 (TENAYA n=334 faricimab and n=337 aflibercept), and between March 11 and Nov 1, 2019 (LUCERNE n=331 faricimab and n=327 aflibercept). BCVA change from baseline with faricimab was non-inferior to aflibercept in both TENAYA (adjusted mean change 5·8 letters [95% CI 4·6 to 7·1] and 5·1 letters [3·9 to 6·4]; treatment difference 0·7 letters [-1·1 to 2·5]) and LUCERNE (6·6 letters [5·3 to 7·8] and 6·6 letters [5·3 to 7·8]; treatment difference 0·0 letters [-1·7 to 1·8]). Rates of ocular adverse events were comparable between faricimab and aflibercept (TENAYA n=121 [36·3%] vs n=128 [38·1%], and LUCERNE n=133 [40·2%] vs n=118 [36·2%]).

INTERPRETATION

Visual benefits with faricimab given at up to 16-week intervals demonstrates its potential to meaningfully extend the time between treatments with sustained efficacy, thereby reducing treatment burden in patients with nAMD.

FUNDING

F Hoffmann-La Roche.

Hyaluronidase-1-mediated glycocalyx impairment underlies endothelial abnormalities in polypoidal choroidal vasculopathy

Background

Polypoidal choroidal vasculopathy (PCV), a subtype of age-related macular degeneration (AMD), is a global leading cause of vision loss in older populations. Distinct from typical AMD, PCV is characterized by polyp-like dilatation of blood vessels and turbulent blood flow in the choroid of the eye. Gold standard anti-vascular endothelial growth factor (anti-VEGF) therapy often fails to regress polypoidal lesions in patients. Current animal models have also been hampered by their inability to recapitulate such vascular lesions. These underscore the need to identify VEGF-independent pathways in PCV pathogenesis.

Results

We cultivated blood outgrowth endothelial cells (BOECs) from PCV patients and normal controls to serve as our experimental disease models. When BOECs were exposed to heterogeneous flow, single-cell transcriptomic analysis revealed that PCV BOECs preferentially adopted migratory-angiogenic cell state, while normal BOECs undertook proinflammatory cell state. PCV BOECs also had a repressed protective response to flow stress by demonstrating lower mitochondrial functions. We uncovered that elevated hyaluronidase-1 in PCV BOECs led to increased degradation of hyaluronan, a major component of glycocalyx that interfaces between flow stress and vascular endothelium. Notably, knockdown of hyaluronidase-1 in PCV BOEC improved mechanosensitivity, as demonstrated by a significant 1.5-fold upregulation of Krüppel-like factor 2 (KLF2) expression, a flow-responsive transcription factor. Activation of KLF2 might in turn modulate PCV BOEC migration. Barrier permeability due to glycocalyx impairment in PCV BOECs was also reversed by hyaluronidase-1 knockdown. Correspondingly, hyaluronidase-1 was detected in PCV patient vitreous humor and plasma samples.

Conclusions

Hyaluronidase-1 inhibition could be a potential therapeutic modality in preserving glycocalyx integrity and endothelial stability in ocular diseases with vascular origin.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-022-01244-z.

Combining retinal and choroidal microvascular metrics improves discriminative power for diabetic retinopathy

PURPOSE

To use optical coherence tomography angiography (OCTA) parameters from both the retinal and choroidal microvasculature to detect the presence and severity of diabetic retinopathy (DR).

METHOD

This is a cross-sectional case-control study. OCTA parameters from retinal vasculature, fovea avascular zone (FAZ) and choriocapillaris were evaluated from 3×3 mm² fovea-centred scans. Areas under the receiver operating characteristic (ROC) curve were used to compare the discriminative power on the presence of diabetes mellitus (DM), the presence of DR and need for referral: group 1 (no DM vs DM no DR), group 2 (no DR vs any DR) and group 3 (non-proliferative DR (NPDR) vs proliferative DR (PDR)).

RESULTS

35 eyes from 27 participants with no DM and 132 eyes from 75 with DM were included. DR severity was classified into three groups: no DR group (62 eyes), NPDR (51 eyes), PDR (19 eyes). All retinal vascular parameters, FAZ parameters and choriocapillaris parameters were strongly altered with DR stages (p<0.01), except for the deep plexus FAZ area (p=0.619). Choriocapillaris parameters allowed to better discriminate between no DM versus DM no DR group compared with retinal parameters (areas under the ROC curve=0.954 vs 0.821, p=0.006). A classification model including retinal and choroidal microvasculature significantly improved the discrimination between DR and no DR compared with each parameter separately (p=0.029).

CONCLUSIONS

Evaluating OCTA parameters from both the retinal and choroidal microvasculature in 3×3 mm scans improves the discrimination of DM and early DR.

Gene-Based Therapeutics for Inherited Retinal Diseases

Inherited retinal diseases (IRDs) are a heterogenous group of orphan eye diseases that typically result from monogenic mutations and are considered attractive targets for gene-based therapeutics. Following the approval of an IRD gene replacement therapy for Leber's congenital amaurosis due to RPE65 mutations, there has been an intensive international research effort to identify the optimal gene therapy approaches for a range of IRDs and many are now undergoing clinical trials. In this review we explore therapeutic challenges posed by IRDs and review current and future approaches that may be applicable to different subsets of IRD mutations. Emphasis is placed on five distinct approaches to gene-based therapy that have potential to treat the full spectrum of IRDs: 1) gene replacement using adeno-associated virus (AAV) and nonviral delivery vectors, 2) genome editing via the CRISPR/Cas9 system, 3) RNA editing by endogenous and exogenous ADAR, 4) mRNA targeting with antisense oligonucleotides for gene knockdown and splicing modification, and 5) optogenetic approaches that aim to replace the function of native retinal photoreceptors by engineering other retinal cell types to become capable of phototransduction.