Expanding the genetic landscape of Usher syndrome type IV caused by pathogenic ARSG variants.

Usher syndrome (USH) is the most common cause of deafblindness. USH is autosomal recessively inherited and characterized by rod-cone dystrophy or retinitis pigmentosa (RP), often accompanied by sensorineural hearing loss. Variants in >15 genes have been identified as causative for clinically and genetically distinct subtypes. Among the ultra-rare and recently discovered genes is ARSG, coding for the lysosomal sulfatase Arylsulfatase G. This subtype was assigned as "USH IV" with a late onset of RP and usually late-onset progressive SNHL without vestibular involvement. Here, we describe nine new subjects and the clinical description of four cases with the USH IV phenotype bearing seven novel and two known pathogenic variants. Functional experiments indicated the complete loss of sulfatase enzymatic activity upon ectopic expression of mutated ARSG cDNA. Interestingly, we identified a homozygous missense variant, p.(Arg99His), previously described in dogs with neuronal ceroid lipofuscinosis. Our study expands the genetic landscape of ARSG-USH IV and the number of known subjects by more than 30%. These findings highlight that USH IV likely has been underdiagnosed and emphasize the need to test molecularly unresolved subjects with deafblindness syndrome. Finally, testing of ARSG should be considered for the genetic work-up of apparent isolated inherited retinal diseases.

Prognostic impact of hyperreflective foci in nonsyndromic retinitis pigmentosa.

PURPOSE: To evaluate the prognostic impact of hyperreflective foci (HRF) on spectral-domain optical coherence tomography (SD-OCT) in nonsyndromic retinitis pigmentosa (RP). METHODS: Retrospective, single-center cohort study including genetically-tested RP patients with a minimum follow-up of 24 months. Clinical data including demographics, genetic results and best-corrected visual acuity (BCVA) at baseline and follow-up were collected. Horizontal and vertical SD-OCT scans were analyzed by 2 independent graders. Outer nuclear layer (ONL) thickness and ellipsoid zone (EZ) width were manually measured in horizontal and vertical scans. HRF were classified according to location: outer retinal layers within the central 3mm (central-HRF), outer retinal layers beyond the central 3mm (perifoveal-HRF), and choroid (choroidal-HRF). Central macular thickness (CMT), central point thickness (CPT) and choroidal thickness (CT) at baseline and follow-up were also recorded. RESULTS: A total of 175 eyes from 94 RP patients (47.9% female, mean age 50.7±15.5 years) were included, with a mean follow-up of 29.24±7.17 months. Mean ETDRS (early treatment diabetic retinopathy study) BCVA decreased from 61.09±23.54 to 56.09±26.65 (p=0.082). At baseline, 72 eyes (41.1%) showed central-HRF, 110 eyes (62.9%) had perifoveal-HRF and 149 eyes (85.1%) exhibited choroidal-HRF. Central-HRF and perifoveal-HRF were associated with worse final BCVA, as well as greater BCVA deterioration (all p<0.0029). Only central-HRF were associated with a worse final CMT (p<0.001). Shorter EZ widths were associated with all types of HRF (p<0.05). Perifoveal and choroidal-HRF predicted smaller final EZ areas (p<0.01). CONCLUSION: HRF are highly prevalent in RP patients and appear to have a negative prognostic impact in visual function and EZ area.

Genetic profile of syndromic retinitis pigmentosa in Portugal.

PURPOSE: Retinitis pigmentosa (RP) comprises a genetically and clinically heterogeneous group of inherited retinal degenerations, where 20-30% of patients exhibit extra-ocular manifestations (syndromic RP). Understanding the genetic profile of RP has important implications for disease prognosis and genetic counseling. This study aimed to characterize the genetic profile of syndromic RP in Portugal. METHODS: Multicenter, retrospective cohort study. Six Portuguese healthcare providers identified patients with a clinical diagnosis of syndromic RP and available genetic testing results. All patients had been previously subjected to a detailed ophthalmologic examination and clinically oriented genetic testing. Genetic variants were classified according to the American College of Medical Genetics and Genomics; only likely pathogenic or pathogenic variants were considered relevant for disease etiology. RESULTS: One hundred and twenty-two patients (53.3% males) from 100 families were included. Usher syndrome was the most frequent diagnosis (62.0%), followed by Bardet-Biedl (19.0%) and Senior-Løken syndromes (7.0%). Deleterious variants were identified in 86/100 families for a diagnostic yield of 86.0% (87.1% for Usher and 94.7% for Bardet-Biedl). A total of 81 genetic variants were identified in 25 different genes, 22 of which are novel. USH2A and MYO7A were responsible for most type II and type I Usher syndrome cases, respectively. BBS1 variants were the cause of Bardet-Biedl syndrome in 52.6% of families. Best-corrected visual acuity (BCVA) records were available at baseline and last visit for 99 patients (198 eyes), with a median follow-up of 62.0 months. The mean BCVA was 56.5 ETDRS letters at baseline (Snellen equivalent ~ 20/80), declining to 44.9 ETDRS letters (Snellen equivalent ~ 20/125) at the last available follow-up (p < 0.001). CONCLUSION: This is the first multicenter study depicting the genetic profile of syndromic RP in Portugal, thus contributing toward a better understanding of this heterogeneous disease group. Usher and Bardet-Biedl syndromes were found to be the most common types of syndromic RP in this large Portuguese cohort. A high diagnostic yield was obtained, highlighting current genetic testing capabilities in providing a molecular diagnosis to most affected individuals. This has major implications in determining disease-related prognosis and providing targeted genetic counseling for syndromic RP patients in Portugal.

Genetic Testing of Patients with Inherited Retinal Diseases in the European Countries: An International Survey by the European Vision Institute.

INTRODUCTION: The purpose of this project was to explore the current standards of clinical care genetic testing and counseling for patients with inherited retinal diseases (IRDs) from the perspective of leading experts in selected European countries. Also, to gather opinions on current bottlenecks and future solutions to improve patient care. METHODS: On the initiative of the European Vision Institute, a survey questionnaire with 41 questions was designed and sent to experts in the field from ten European countries. Each participant was asked to answer with reference to the situation in their own country. RESULTS: Sixteen questionnaires were collected by November 2023. IRD genetic tests are performed in clinical care settings for 80% or more of tested patients in 9 countries, and the costs of genetic tests in clinical care are covered by the public health service to the extent of 90% or more in 8 countries. The median proportion of patients who are genetically tested, the median rate of genetically solved patients among those who are tested, and the median proportion of patients receiving counseling are 51-70%, 61-80%, and 61-80%, respectively. Improving the education of healthcare professionals who facilitate patient referrals to specialized centers, improving access of patients to more thorough genotyping, and increasing the number of available counselors were the most advocated solutions. CONCLUSION: There is a significant proportion of IRD patients who are not genetically tested, whose genetic testing is inconclusive, or who do not receive counseling. Educational programs, greater availability of state-of-the-art genotyping and genetic counselors could improve healthcare for IRD patients.

Genetic spectrum, retinal phenotype, and peripapillary RNFL thickness in RPGR heterozygotes.

PURPOSE: Phenotypic heterogeneity with variable severity has been reported in female carriers of retinitis pigmentosa GTPase regulator (RPGR) mutations, including a male-type phenotype. A phenomenon not fully understood is peripapillary retinal nerve fiber layer (pRNFL) thickening in male patients with RPGR-associated X-linked retinitis pigmentosa, especially in the temporal sector. We aim to describe the genetic spectrum, retinal phenotypes, and pRNFL thickness in a cohort of Caucasian RPGR-mutation heterozygotes. METHODS: A cross-sectional study was conducted at an inherited retinal degeneration (IRD) reference center in Portugal. Female patients heterozygous for clinically significant RPGR variants were identified using the IRD-PT registry. A complete ophthalmologic examination was performed, complemented by macular and peripapillary spectral domain optical coherence tomography (SD-OCT), ultra-widefield color fundus photography (UW-CFP), and ultra-widefield fundus autofluorescence (UW-FAF). The retinal phenotypes were graded according to previously described classifications. The pRNFL thickness across the superior, inferior, nasal, and temporal quadrants was compared to the Spectralis® RNFL age-adjusted reference database. RESULTS: Forty-eight eyes from 24 females (10 families) were included in the study. Genetic analysis yielded 8 distinct clinically significant frameshift variants in RPGR gene, 3 of which herein reported for the first time. No association was found between mutation location and best-corrected visual acuity (BCVA) or retinal phenotype. Age was associated with worse BCVA and more advanced phenotypes on SD-OCT, UW-CFP, and UW-FAF. Seven women (29.17%) presented a male-type phenotype on UW-FAF in at least one eye. An association was found between UW-FAF and pRNFL thickness in the temporal sector (p = 0.003), with the most advanced fundus autofluorescence phenotypes showing increased pRNFL thickness in this sector. CONCLUSION: This study expands the genetic landscape of RPGR-associated disease by reporting 3 novel clinically significant variants. We have shown that clinically severe phenotypes are not uncommon among female carriers. Furthermore, we provide novel insights into pRNFL changes observed in RPGR heterozygotes that mimic what has been reported in male patients.

Current Management of Inherited Retinal Degeneration Patients in Europe: Results of a 2-Year Follow-Up Multinational Survey by the European Vision Institute Clinical Research Network - EVICR.net.

INTRODUCTION: An increasing number of gene-specific therapies are being developed for inherited retinal degenerations (IRDs). Identification of well-characterized patients is an emerging need. We conducted the second multinational survey among the EVICR.net and ERN-EYE members to understand the management and treatment of IRDs in Europe and compared it to the 2019 survey. METHODS: An electronic survey questionnaire was developed and sent to 124 clinical centers (25 countries) by June/July 2021. Statistical analysis was performed with Excel and R. RESULTS: The overall response rate was 44% but varied among countries. Only 9% of responding centers do not see IRD patients (2019 survey 14%), 42% follow at least 200 patients per year, 18% follow 500-999, and 2% more than 1,000. Databases exist in 86% of the centers (local 86%; national web based 12%). IRD patients are referred to EVICR.net and ERN-EYE centers mainly by general ophthalmologists, patient self-referral, or medical retina specialists. Most IRD patients are first seen as adults. Signs and symptoms depend on age of onset: in infancy, nystagmus; at older age, night blindness and reduced visual field; reduced visual acuity is described at any age. Comprehensive ophthalmic examination always includes visual acuity and almost always visual field multimodal retinal imaging, electrophysiology, color vision testing, and refraction. Identification of genotypes is successful in 72% of centers in 40-80% of cases (2019 survey 69% of centers). The time for confirmation of the genetic diagnosis varies from 2-4 weeks to 24 months (2019 survey >4 weeks ≤10 years). Genetic testing is covered by public health service in 83%, private health insurance in 29%, research funds in 24%; 5% do not have access to genetic testing (2019 survey 15%). The most striking result is the high increase in the involvement of centers in natural history and gene therapy trials that more than doubled for the latter. DISCUSSION: This second multinational survey on management of IRDs in Europe highlights persistent important differences in the number of IRD patients managed per center, comparable diagnostic work-up, and increasing genotyping in diagnostic laboratories. The important increase in involvement of centers in natural history and gene therapy trials reflects the rapidly evolving field of gene therapy development. The survey provides important follow-up data for researchers, clinicians, caregivers, patient advocate groups, pharmaceutical companies, and investors.

Current Management of Patients with RPE65 Mutation Associated Inherited Retinal Degenerations in Europe: Results of a 2-Year Follow-Up Multinational Survey.

INTRODUCTION: The aim of this study was to evaluate the current management of RPE65 biallelic mutation-associated inherited retinal degeneration (RPE65-IRD) in Europe since market authorization of voretigene neparvovec (VN, LuxturnaTM) in 2018. By July 2022, over 200 patients have been treated outside the USA, of whom about 90% in Europe. We conducted among all centers of the European Vision Institute Clinical Research Network (EVICR.net) and health care providers (HCPs) of the European Reference Network dedicated to Rare Eye Diseases (ERN-EYE) the second multinational survey on management of IRDs in Europe elaborated by EVICR.net with a special focus on RPE65-IRD. METHODS: An electronic survey questionnaire with 48 questions specifically addressing RPE65-IRD (2019 survey 35) was developed and sent by June 2021 to 95 EVICR.net centers and 40 ERN-EYE HCPs and affiliated members. Of note, 11 centers are members of both networks. Statistical analysis was performed with Excel and R. RESULTS: The overall response rate was 44% (55/124); 26 centers follow RPE65 biallelic mutation-associated IRD patients. By June 2021, 8/26 centers have treated 57 RPE65-IRD cases (1-19/center, median 6) and 43 planned for treatment (range 0-10/center, median 6). The overall age range was 3-52 years, and on average 22% of the patients did not (yet) qualify for treatment (range 2-60%/center, median 15%). Main reasons were too advanced (range 0-100, median 75%) or mild disease (range 0-100, median 0). Eighty-three percent of centers (10/12) that follow RPE65 mutation-associated IRD patients treated with VN participate in the PERCEIVE registry (EUPAS31153, http://www.encepp.eu/encepp/viewResource.htm?id=37005). Quality of life and full-field stimulus test improvements had the highest scores of the survey-reported outcome parameters in VN treatment follow-up. CONCLUSION: This second multinational survey on management of RPE65-IRD by EVICR.net centers and ERN-EYE HCPs in Europe indicates that RPE65-IRD might be diagnosed more reliably in 2021 compared to 2019. By June 2021, 8/26 centers reported detailed results including VN treatment. Main reasons for non-treatment were too advanced or mild disease, followed by absence of 2 class 4 or 5 mutations on both alleles or because of a too young age. Patient satisfaction with treatment was estimated to be high by 50% of the centers.

TLR7 and TLR8 evolution in lagomorphs: different patterns in the different lineages.

Toll-like receptors (TLRs) are one of the most ancient and widely studied innate immune receptors responsible for host defense against invading pathogens. Among the known TLRs, TLR7 and TLR8 sense and recognize single-stranded (ss) RNAs with a dynamic evolutionary history. While TLR8 was lost in birds and duplicated in turtles and crocodiles, TLR7 is duplicated in some birds, but in other tetrapods, there is only one copy. In mammals, with the exception of lagomorphs, TLR7 and TLR8 are highly conserved. Here, we aim to study the evolution of TLR7 and TLR8 in mammals, with a special focus in the order Lagomorpha. By searching public sequence databases, conducting evolutionary analysis, and evaluating gene expression, we were able to confirm that TLR8 is absent in hares but widely expressed in the European rabbit. In contrast, TLR7 is absent in the European rabbit and quite divergent in hares. Our results suggest that, in lagomorphs, more in particular in leporids, TLR7 and TLR8 genes have evolved faster than in any other mammalian group. The long history of interaction with viruses and their location in highly dynamic telomeric regions might explain the pattern observed.

Frequency of cystoid macular edema and vitreomacular interface disorders in genetically solved syndromic and non-syndromic retinitis pigmentosa.

PURPOSE: Retinitis pigmentosa (RP) corresponds to a group of inherited retinal disorders where progressive rod-cone degeneration is observed. Cystoid macular edema (CME) and vitreomacular interface disorders (VMID) are known to complicate the RP phenotype, challenging an age-old concept of retained central visual acuity. The reported prevalence of these changes varies greatly among different studies. We aim to describe the frequency of CME and VMID and identify predictors of these changes in a cohort of Caucasian patients with genetically solved syndromic (sRP) and non-syndromic RP (nsRP). METHODS: Cross-sectional study of patients with genetically solved sRP or nsRP. Genetic testing was clinically oriented in all probands and coordinated by a medical geneticist. The presence/absence of CME and VMIDs such as epiretinal membrane (ERM), vitreomacular traction (VMT), lamellar hole (LH), macular hole (MH), and macular pseudohole (MPH), and the integrity of the neurosensory retina and retinal pigment epithelium were evaluated in individual macular SD-OCT b-scans. Mixed-effects regression analysis models were used to identify significant predictors of BCVA, CME, and VMID. Significance was considered at α < 0.05. RESULTS: We included 250 eyes from 125 patients. Mean age was 44.9 ± 15.7 years and 55.2% were male. Eighty-eight patients had nsRP and 37 had sRP. Median BCVA was 0.5 (0.2-1.3) logMAR. CME was found in 17.1% of eyes, while ERM was found in 54.3% of eyes. The frequency of CME (p = 0.45) and ERM (p = 0.07) did not differ between sRP and nsRP patients, nor across different inheritance patterns. Mixed-effects univariate linear regression identified age (p = 0.04), cataract surgery (p < 0.01), and loss of integrity of outer retinal layers (p < 0.01) as significant predictors of lower visual acuity, while increased foveal thickness (p < 0.01) and the presence of CME (p = 0.04) were predictors of higher visual acuity. On mixed-effects multivariable analysis, only increased foveal thickness was significantly associated with better visual acuity (p < 0.01). CONCLUSION: We found that the burden of ERM and CME in RP patients is high, highlighting the importance of screening for these potentially treatable conditions to improve the quality of life of RP patients.

EYS-Associated Sector Retinitis Pigmentosa.

PURPOSE: Sector retinitis pigmentosa (RP) is a rare form of rod-cone degeneration typically associated with mutations in the RHO gene. We describe six unrelated patients presenting with this atypical phenotype in association with biallelic mutations in EYS gene. METHODS: Multinational, multicentre cross-sectional case series. Patients with biallelic disease-causing variants in EYS and a clinical diagnosis of sector RP were recruited from specialized centres in Portugal and Brazil. All patients underwent a comprehensive ophthalmologic examination complemented by deep phenotyping. Peripheral blood samples were collected from all probands and available relatives for genetic analysis. Genetic counselling was provided to all subjects. RESULTS: Seven disease-causing variants (4 pathogenic; 3 likely pathogenic) were identified in 6 unrelated female patients. Best-corrected visual acuity ranged from 75 to 85 ETDRS letters. All eyes showed bilateral and symmetrical areas of outer retinal atrophy distributed along the inferior vascular arcades and extending temporally and/or nasally in a crescent-shaped pattern. On fundus autofluorescence (AF), a foveal-sparing curvilinear band of hyperAF encroaching the optic nerve head and extending temporally was seen in 4 patients. The remaining 2 presented bilateral and symmetrical patches of hypoAF inside crescent-shaped areas of hyperAF along the inferior temporal vascular arcade. Visual field testing revealed superior visual field defects of varying extents, always in close association with the fundus AF findings. CONCLUSIONS: Even though EYS has only recently been listed as a cause of the sector RP phenotype, we believe that this presentation is not infrequent and should be considered an important differential for sector RP.

A novel compound heterozygous BEST1 gene mutation in two siblings causing autosomal recessive bestrophinopathy.

PURPOSE: To describe the clinical features, imaging characteristics, and genetic test results associated with a novel compound heterozygous mutation of the BEST1 gene in two siblings with autosomal recessive bestrophinopathy. METHODS: Two siblings underwent a complete ophthalmic examination, including dilated fundus examination, fundus photography, fundus autofluorescence imaging, spectral-domain optical coherence tomography, fluorescein angiography, electroretinography, and electrooculography. A clinical diagnosis of autosomal recessive bestrophinopathy was established based on ocular examination and multimodal retinal imaging. Subsequently, clinical exome sequencing consisting of a panel of 6670 genes was carried out to confirm the diagnosis and assess genetic alterations in the protein-coding region of the genome of the patients. The identified mutations were tested in the two affected siblings and one of their parents. RESULTS: Two siblings (a 17-year-old female and a 15-year-old male) presented with reduced visual acuity and bilaterally symmetrical subretinal deposits of hyperautofluorescent materials in the posterior pole, which showed staining in the late phase of fluorescein angiogram. Spectral-domain optical coherence tomography demonstrated hyperreflective subretinal deposits and subretinal fluid accumulation. Both patients shared two mutations in the protein-coding region of the BEST1 gene, c.103G > A, p.(Glu35Lys) and c.313C > A, p.(Arg105Ser) (a novel disease-causing mutation). Sanger sequencing confirmed that the unaffected mother of the proband was carrying p.(Glu35Lys) variant in a heterozygous state. CONCLUSIONS: We have identified and described the phenotype of a novel disease-causing mutation NM_004183.4:c.313C > A, p.(Arg105Ser) in a heterozygous state along with a previously reported mutation NM_004183.4:c.103G > A, p.(Glu35Lys) of the BEST1 gene in two related patients with autosomal recessive bestrophinopathy.

Clinical/Demographic Functional Testing and Multimodal Imaging Differences between Genetically Solved and Unsolved Retinitis Pigmentosa.

INTRODUCTION: The purpose of this study was to compare clinical/demographic functional testing and multimodal imaging features between genetically solved and genetically unsolved nonsyndromic retinitis pigmentosa (nsRP) patients. METHODS: A cross-sectional study was conducted at an inherited retinal dystrophies reference center. Consecutive patients with nsRP and available genetic testing results performed between 2018 and 2020 were included. Genetic testing was clinically oriented, and variants were classified according to the American College of Medical Genetics and Genomics. Only class IV or V variants were considered disease-causing. Clinical/demographic, functional, and imaging features were compared between genetically unsolved (G1) and genetically solved (G2) patients. RESULTS: A total of 175 patients (146 families) were included: 68 patients (59 families) in G1 and 107 patients (87 families) in G2. First symptoms <25 years, consanguinity, evidence for a particular inheritance pattern, and the absence of indicators for phenocopies were significantly more prevalent in G2. No significant differences were observed on best-corrected visual acuity. The visual field index and mean central retinal layer thickness were significantly higher in G1. The frequency of atypical features on multimodal imaging did not differ between groups. CONCLUSION: Individual clinical/demographic functional testing and multimodal imaging features should be considered when counseling patients about the probability of identifying disease-causing variants.

Non-exudative macular neovascularization in pseudoxanthoma elasticum.

PURPOSE: To characterize morphological changes in the retina and to report the frequency and natural history of non-exudative macular neovascularization (MNV) in a cohort of pseudoxanthoma elasticum (PXE). METHODS: A single-center, retrospective study was complemented by a cross-sectional examination. Consecutive patients with a definitive genetic and/or clinical diagnosis of PXE, visiting our department between January 2019 and December 2019, and with a minimum follow-up of 6 months were recruited. Baseline data were retrieved from each patient file. Additionally, a cross-sectional examination comprising color fundus photography, spectral-domain optical coherence tomography (SD-OCT), OCT-Angiography (OCT-A), and fundus autofluorescence was performed. The presence of typical PXE-related findings, as well as related complications, was multimodally evaluated. The prevalence and natural history of non-exudative MNV were assessed. All images were graded by two independent graders. RESULTS: Forty-eight eyes from 24 patients (mean age 59.11 ± 18.14) with a median follow-up of 53.00 months were included. Angioid streaks and peau d'orange were observed in 46/48 and 42/48 eyes, while MNV was present in 75.00% of the cohort. The prevalence of non-exudative MNV was 33.33% (6/18). In the 2 eyes that developed exudation, time to conversion was 9.50 ± 4.95 months. No significant difference in visual acuity was found between eyes with non-exudative MNV and those with no signs of MNV. CONCLUSION: We have shown that non-exudative MNV is a frequent finding in PXE but the majority of eyes did not develop exudation during follow-up. Our results are a clear evidence of the utility of OCT-A in the management of PXE.

Retinal layer thicknesses and neurodegeneration in early age-related macular degeneration: insights from the Coimbra Eye Study.

PURPOSE: This study aims to analyze the retinal layers and choroidal thickness in a large set of eyes with early age-related macular degeneration (AMD), in order to detect differences by stage suggestive of early neurodegeneration, and to explore biomarkers of different phenotypes. METHODS: This study is a population-based, cross-sectional study. Patients from the incidence AMD study (NCT02748824) with early AMD (Rotterdam 2a, 2b, 3) were included. All performed spectral-domain optical coherence tomography (SD-OCT) (Spectralis, Heidelberg Engineering, Germany) and automatic segmentation of all retinal layers was obtained with built-in software. Manual correction was performed whenever necessary. The mean thicknesses (ETDRS grid) and volume of each layer were recorded. Subfoveal choroidal thickness was manually measured. Estimates for each layer thickness were calculated with linear mixed models and tested for pairwise differences between stages. Associations between layer thickness and microstructural findings were assessed by multivariate regression analysis. RESULTS: The final cohort comprised 346 eyes (233 patients): 82.66% (n = 286) in stage 2a, 5.49% (n = 19) in stage 2b, and 11.85% (n = 41) in stage 3. A global tendency for lower/inferior thickness of the neuroretinal layers was found comparing stage 3 to 2a: retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and inner plexiform layer (IPL) were inferior in the inner/outer ETDRS circles and the outer nuclear layer (ONL) and photoreceptors' segments layer in the central circle (p ≤ 0.002). The retinal pigment epithelium-Bruch's membrane (RPE/BrM) layer was thicker in stage 3 (p ≤ 0.001). Subretinal drusenoid deposits (SDD) were associated with thinner neuroretinal layers and choroid (p < 0.05). CONCLUSIONS: Our results showed in a large population-based dataset that several inner and outer neuroretinal layers were thinner with a higher stage in early AMD. These findings support the existence of early and progressive neurodegeneration. Neuronal retinal layer thicknesses might thus be used as quantitative biomarkers of disease progression in AMD. The presence of SDD is possibly associated to more prominent and faster neurodegeneration.

Sole head transcriptomics reveals a coordinated developmental program during metamorphosis.

Most teleosts undergo a thyroid hormone (TH) regulated larval to juvenile transition known as metamorphosis. In Pleuronectiformes (flatfish), metamorphosis is most dramatic, and one eye of the symmetric pelagic larvae migrates to the opposite side of the head, giving rise to an asymmetric benthic juvenile with both eyes on the same side of the body. Asymmetric development occurs mostly in the head. To understand the genetic mechanisms underlying this developmental change we have generated a Solea senegalensis metamorphosing flatfish head transcriptome. Our results reveal that THs acting as integrative factors direct a stepwise genetic program that initiates a specific organismal level response followed by cell specific responses that lead to the long-term changes that characterise the post-metamorphic identity and physiology of the head. Flatfish head asymmetric development during metamorphosis and its TH dependency is conserved thus we consider the findings in sole most likely representative of all flatfish species.

Incidence of Age-Related Macular Degeneration in the Central Region of Portugal: The Coimbra Eye Study - Report 5.

PURPOSE: To describe the 6.5-year incidence and progression of age-related macular degeneration (AMD) in a coastal town of central Portugal. METHODS: Population-based cohort study. Participants underwent standardized interviews and ophthalmological examination. Color fundus photographs were graded according to the International Classification and Grading System for AMD and ARM. The crude and age-standardized incidence of early and late AMD was calculated, and progression was analyzed. RESULTS: The 6.5-year cumulative incidence of early AMD was 10.7%, and of late AMD it was 0.8%. The incidence of early AMD was 7.2, 13.1 and 17.7% for participants aged 55-64, 65-74 and 75-84 years (p < 0.001). The late AMD incidence was 0.3, 0.9 and 2.8% for the corresponding age groups (p = 0.003). The age-standardized incidence was 10.8% (95% CI, 10.74-10.80%) for early and 1.0% (95% CI, 1.00-1.02%) for late AMD. The incidence of both neovascular AMD and geographic atrophy was 0.4%. Progression occurred in 17.2% of patients. CONCLUSION: The early AMD incidence in a coastal town of central Portugal was found to be similar to that of major epidemiological studies of European-descent populations; however, the incidence of late AMD was lower, and further analysis on risk factors will be conducted.

Epiretinal Proliferations Associated with Lamellar Macular Holes: Clinical and Surgical Implications.

OBJECTIVES: To describe the prevalence of lamellar hole-associated epiretinal proliferation (LHEP) and to correlate this finding with lamellar macular hole (LMH) morphology and prognosis after a surgical or conservative approach. METHODS: This is a retrospective multicenter case series comprising consecutive LMH patients followed for ≥6 months. Serial spectral-domain optical coherence tomographies were evaluated for the presence of epiretinal membrane (ERM) and LHEP, diameter of the LMH aperture, base, and floor thickness. Pars plana vitrectomy with ERM and internal limiting membrane peeling was performed in the surgical cases. RESULTS: A total of 62 eyes from 57 consecutive patients were included. Mean follow-up time was 27.1 ± 19.8 months. LHEP was observed in 33 (53.2%) eyes. Patients with LMH and LHEP presented a larger external diameter (p = 0.001) and thinner floors (p = 0.018). Twenty-seven (81.8%) of the patients with LMH and LHEP presented a degenerative intraretinal cavitation, compared to 23.3% in the non-LHEP group (p = 0.001). No differences were observed in visual performance or closure rate between the 2 groups after surgery or in the subset of patients followed conservatively. CONCLUSIONS: LHEP was correlated with the anatomical conformation of the LMH, yielding thinner floors and larger external diameters. However, it did not correlate with the anatomical or functional results, both in the patients who underwent surgery and in those managed conservatively.

Multimodal Evaluation of the Fellow Eye of Patients with Retinal Angiomatous Proliferation.

INTRODUCTION: We conducted a multimodal, cross-sectional evaluation. METHODS: Eyes were divided into 4 study groups: controls, early/intermediate age-related macular degeneration (AMD), fellow eyes of retinal angiomatous proliferation (RAP), and RAP eyes. Patients were evaluated with spectral-domain optical coherence tomography (OCT), enhanced depth imaging-OCT, and OCT angiography (OCTA). OCTA images were processed to generate maps of the vessel density and perfusion density of the superficial and deep retinal layers (SRL and DRL) and the choriocapillaris level (CL). The thickness of the outer nuclear layer and choroid was manually assessed. RESULTS: We included 135 eyes of 100 patients (51 controls, 30 AMD, 42 RAP, and 12 fellow eyes). The fellow eyes showed a significantly lower vascular perfusion of the SRL, DRL, and CL (p < 0.02) than the early/intermediate AMD and control eyes did. Similarly, RAP eyes presented a lower vascular perfusion of the DRL and CL (p < 0.05). Besides, structural analyses of the fellow eyes and RAP eyes revealed a significantly higher prevalence of macular pigmentary changes, atrophy of the retinal pigment epithelium, hyperreflective "clumps" above flat drusen, amongst others, than early/intermediate AMD and control eyes (p < 0.05). CONCLUSION: We present the first report on the OCTA analysis of the fellow eye of patients with RAP. The reduced perfusion density and vessel density observed contributes, in association with clearly defined structural changes, to a wider characterization of RAP as a distinctive phenotype.