INTRAOCULAR EMULSION OF SILICONE OIL (ITEMS) GRADING SYSTEM: An Evidence-Based Expert-Led Consensus.

PURPOSE: To propose the InTraocular EMulsion of Silicone oil (ITEMS) grading system for the assessment of silicone oil (SiO) emulsion, applicable in a routine clinical setting and validated through an expert-led consensus procedure. METHODS: Seven experts on intraocular liquid tamponades, led by a facilitator, performed a literature review on the detection of SiO emulsion. Based on the proposed ideas, a questionnaire was developed and submitted to the experts on the methods to detect SiO emulsion and the items to grade. After 2 rounds of individual ranking using a 9-point scale and related discussion, the final grading system was developed including items that reached consensus (score ≥7 from ≥75% of members). RESULTS: The agreed ITEMS grading system includes the identification of SiO microbubbles and large SiO bubbles through slit-lamp biomicroscopy, gonioscopy, fundus examination under mydriasis, or ultra-wide-field fundus photography. Moreover, macular and disk optical coherence tomography are used to detect SiO-associated hyperreflective dots. CONCLUSION: An evidence-based expert-led consensus was conducted to develop grading system of SiO emulsion, allowing, for the first time, homogenous collection of data on SiO emulsion. This has the potential to improve the understanding of the role and clinical relevance of SiO emulsion, allowing comparisons between different studies.

Pathophysiology of Age-Related Macular Degeneration: Implications for Treatment.

Age-related macular degeneration (AMD) is a complex, multifactorial, progressive retinal disease that affects millions of people worldwide and has become the leading cause of visual impairment in developed countries. The disease etiopathogenesis is not understood fully, although many triggers and processes that lead to dysfunction and degeneration of the retinal pigment epithelium (RPE) have already been identified. Thus, the lack of cellular control of oxidative stress, altered proteostasis, dysfunction of lipid homeostasis, and mitochondrial dysfunction form an internal feedback loop that causes the RPE to fail and allows accumulation of abnormal misfolded proteins and abnormal lipids that will form drusen. An inadequate antioxidant response, deficits in autophagy mechanisms, and dysregulation of the extracellular matrix (ECM) help to increase the deposition of abnormal drusen material over time. The drusen then act as inflammatory centers that trigger chronic inflammation of the subretinal space in which microglia and recruited macrophages are also involved, and where the complement system is a key component. Choriocapillaris degeneration and nutritional influences are also classic elements recognized in the AMD pathophysiology. The genetic component of the disease is embodied in the recognition of the described risk or protective polymorphisms of some complement and ECM related genes (mainly CFH and ARMS2/HTRA1). Thus, carriers of the risk haplotype at ARMS2/HTRA1 have a higher risk of developing late AMD at a younger age. Finally, gut microbiota and epigenetics may play a role in modulating the progression to advanced AMD with the presence of local inflammatory conditions. Because of multiple implicated processes, different complex combinations of treatments will probably be the best option to obtain the best visual results; they in turn will differ depending on the type and spectrum of disease affecting individual patients or the disease stage in each patient at a specific moment. This will undoubtedly lead to personalized medicine for control and hopefully find a future cure. This necessitates the continued unraveling of all the processes involved in the pathogenesis of AMD that must be understood to devise the combinations of treatments for different concurrent or subsequent problems.

Progression of myopic maculopathy in a Caucasian cohort of highly myopic patients with long follow-up: a multistate analysis.

PURPOSE: This study aims to determine the probability of progression of myopic maculopathy according to age. METHODS: This is a longitudinal observational study of single-center retrospective cohort of Caucasian patients formed by 212 consecutive adults with high myopia. Main outcome measures were age, visual acuity (VA), refractive error (RE), follow-up time, and the macular status assessed at least 5 years apart according to the Meta-Analysis of Pathologic Myopia Study Group. The progression rate was calculated based on per 1000 eyes/year. Multistate models were fitted to identify the predictive factors and to calculate the most probable age of progression onset using the Aalen-Johansen estimator. RESULTS: We studied 220 eyes of 122 Caucasian patients. Mean age was 48.18 ± 14.1, mean follow-up 12.73 ± 5.81 years. One-hundred and fifty-two (69.1%) eyes progressed of category, and 96 (44%) worsened a mean of 0.3 logMAR units during follow-up. The progression rate was 32.21/1000 eyes/year. The probability of progressing increased with age; it was higher in women if there was a family history of myopia, worse VA, higher RE, or wide macular staphyloma. The probability of progressing from category 1 was > 0.6 after 70 years of age; from category 2, it was 0.7 after 70 years; and 0.5 from category 3 after 75 years. If choroidal neovascularization (CNV) appeared, this probability exceeded 0.7 between ages 45 and 55 for all categories. CONCLUSION: The progression rate is lower than in a Japanese series. The vision worsened with disease progression, and the probability of both happening increased after the age of 70-75. If CNV appears, the risk of progression is very high at the age of 45-55.

Monochromatic higher order aberrations in highly myopic eyes with Staphyloma.

BACKGROUND: Prevalence of high myopia is continuously increasing, thus, patients affected with staphyloma are abundant worldwide. Assessment of the quality of vision in these patients is mandatory for a proper clinical counselling, specially when undergoing surgical procedures that require intraocular lenses implantation. Thus, the purpose of the study was to assess monochromatic higher order aberrations (HOAs) in highly myopic eyes with staphyloma with or without a dome-shaped macula. METHODS: Participants underwent spectral-domain optical coherence tomography, ocular axial biometry, dual Scheimpflug photography and integrated Placido disk topography, and Hartmann-Shack wavefront analysis. Five groups were evaluated: a low-moderate myopia control group (< 6.00 diopters, n = 31) and four high myopia (≥6.00 diopters) groups: eyes without staphyloma (n = 18), eyes with inferior staphyloma (n = 14), eyes with posterior staphyloma without dome-shaped macula (n = 15) and eyes with posterior staphyloma with dome-shaped macula (n = 17). Subsequently, two new groups (including all participants) were created to assess differences between myopia with and without staphyloma. One-way analysis of covariance was performed using age and lens densitometry as covariates. RESULTS: Statistically significant (p ≤ 0.05) differences in anterior corneal fourth-order HOAs were observed between the low-moderate myopia and no-dome-shaped macula (Mean: 0.16 µm) and dome-shaped macula posterior staphyloma groups (Mean: 0.12 µm) in younger patients (≤45 years old). The same groups also showed (p ≤ 0.05) significant differences for anterior corneal primary spherical aberration (Mean: 0.19 and 0.13 µm, respectively). In addition, anterior corneal tetrafoil was significantly higher (p = 0.04) in dome-shaped macula compared to no-dome-shaped macula (Mean: 0.18 vs 0.06 µm, respectively). When all participants were grouped together, significantly lower mean anterior corneal primary spherical aberration (0.15 µm vs. 0.27 µm, p = 0.004) and higher internal primary spherical aberration (0.04 µm vs. -0.06 µm, p = 0.04) was observed in staphyloma compared to no-staphyloma myopic patients. CONCLUSIONS: Eyes with high myopia and staphyloma have less positive anterior corneal primary spherical aberration and less negative internal primary spherical aberration, suggesting that the anterior corneal surface tends to mimic in a specular fashion the posterior pole profile. This corneal behaviour appears to change in patients older than 45 years.

Matrix Metalloproteinases in Age-Related Macular Degeneration (AMD).

Age-related macular degeneration (AMD) is a complex, multifactorial and progressive retinal disease affecting millions of people worldwide. In developed countries, it is the leading cause of vision loss and legal blindness among the elderly. Although the pathogenesis of AMD is still barely understood, recent studies have reported that disorders in the regulation of the extracellular matrix (ECM) play an important role in its etiopathogenesis. The dynamic metabolism of the ECM is closely regulated by matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs). The present review focuses on the crucial processes that occur at the level of the Bruch's membrane, with special emphasis on MMPs, TIMPs, and the polymorphisms associated with increased susceptibility to AMD development. A systematic literature search was performed, covering the years 1990-2020, using the following keywords: AMD, extracellular matrix, Bruch's membrane, MMPs, TIMPs, and MMPs polymorphisms in AMD. In both early and advanced AMD, the pathological dynamic changes of ECM structural components are caused by the dysfunction of specific regulators and by the influence of other regulatory systems connected with both genetic and environmental factors. Better insight into the pathological role of MMP/TIMP complexes may lead to the development of new strategies for AMD treatment and prevention.

A comprehensive dataset of pattern electroretinograms for ocular electrophysiology research.

The Pattern Electroretinogram (PERG) is an essential tool in ophthalmic electrophysiology, providing an objective assessment of the central retinal function. It quantifies the activity of cells in the macula and the ganglion cells of the retina, assisting in the differentiation of macular and optic nerve conditions. In this study, we present the IOBA-PERG dataset, an extensive collection of 1354 transient PERG responses accessible on the PhysioNet repository. These recordings were conducted at the Institute of Applied Ophthalmobiology (IOBA) at University of Valladolid, over an extended period spanning nearly two decades, from 2003 to 2022. The dataset includes 336 records, ensuring at least one PERG signal per eye. The dataset thoughtfully includes demographic and clinical data, comprising information such as age, gender, visual acuity measurements, and expert diagnoses. This comprehensive dataset fills a gap in ocular electrophysiological repositories, enhancing ophthalmology research. Researchers can explore a broad range of eye-related conditions and diseases, leading to enhanced diagnostic accuracy, innovative treatment strategies, methodological advancements, and a deeper understanding of ocular electrophysiology.

Clinical and genetic characterization of patients with eye diseases included in the Spanish Rare Diseases Patient Registry.

BACKGROUND: The low prevalence of rare diseases poses a significant challenge in advancing their understanding. This study aims to delineate the clinical and genetic characteristics of patients with rare eye diseases (RED) enrolled in the Spanish Rare Diseases Patient Registry. METHODS: A total of 864 patients from the registry database were included. Diseases were categorized into inherited retinal dystrophies (n=688); anterior segment diseases (n=48); congenital malformations (n=27); and syndromic diseases with ocular involvement including muscular (n=46), neurological (n=34), or metabolic (n=13); inflammatory diseases (n=4); and tumors (n=4). Data on visual acuity (VA) and/or visual field (VF), symptoms and signs, concurrent diseases in syndromic cases, age of onset and at diagnosis, affected genes, disability rating, inability to work and dependency grade recognition were collected. RESULTS: A mean diagnostic delay of 7 years from symptom onset was observed. Commonly reported symptoms included photophobia, night blindness, and progressive vision loss (≥57% of patients). Cataract was the most prevalent secondary disease (46%), with pseudophakia being the most common ocular surgery (26%). Hearing loss and cardiovascular diseases were the most prevalent concurrent systemic diseases (≥13%). Certificates of disability, incapacity for work, and dependency were held by 87%, 42%, and 19% of patients, respectively. Among the 719 patients with available VA data, 193 (27%) were blind, and 188 (26%) had moderate to severe visual impairment. Over half of the patients (54%) exhibited VF defects, and 216 (25%) had concentric contraction ≤5° or abolished VF. Most had genetic diseases with autosomal recessive (55%), autosomal dominant (30%), X-linked (9%), and mitochondrial (6%) patterns. One patient had mutations in both recessive USH2A and dominant RHO genes simultaneously. Of the 656 patients (75.7%) who underwent genetic testing, only 461 (70.3%) received a positive result (pathogenic or likely pathogenic mutations explaining the phenotype). We found 62 new gene variants related to RED not previously reported in databases of genetic variants related to specific phenotypes. CONCLUSIONS: This study delineates the clinical and genotypic profiles of RED in Spain. Genetic diseases, particularly retinal disorders, predominate, but a significant proportion of affected patients remain genetically undiagnosed, hindering potential gene therapy endeavors. Despite notable improvements in reducing diagnosis delays, it is still remarkable. RED frequently lead to disability and blindness among young populations.

Clinical exome analysis and targeted gene repair of the c.1354dupT variant in iPSC lines from patients with PROM1-related retinopathies exhibiting diverse phenotypes.

BACKGROUND: Inherited retinal dystrophies (IRD) are one of the main causes of incurable blindness worldwide. IRD are caused by mutations in genes that encode essential proteins for the retina, leading to photoreceptor degeneration and loss of visual function. IRD generates an enormous global financial burden due to the lack of understanding of a significant part of its pathophysiology, molecular diagnosis, and the near absence of non-palliative treatment options. Patient-derived induced pluripotent stem cells (iPSC) for IRD seem to be an excellent option for addressing these questions, serving as exceptional tools for in-depth studies of IRD pathophysiology and testing new therapeutic approaches. METHODS: From a cohort of 8 patients with PROM1-related IRD, we identified 3 patients carrying the same variant (c.1354dupT) but expressing three different IRD phenotypes: Cone and rod dystrophy (CORD), Retinitis pigmentosa (RP), and Stargardt disease type 4 (STGD4). These three target patients, along with one healthy relative from each, underwent comprehensive ophthalmic examinations and their genetic panel study was expanded through clinical exome sequencing (CES). Subsequently, non-integrative patient-derived iPSC were generated and fully characterized. Correction of the c.1354dupT mutation was performed using CRISPR/Cas9, and the genetic restoration of the PROM1 gene was confirmed through flow cytometry and western blotting in the patient-derived iPSC lines. RESULTS: CES revealed that 2 target patients with the c.1354dupT mutation presented monoallelic variants in genes associated with the complement system or photoreceptor differentiation and peroxisome biogenesis disorders, respectively. The pluripotency and functionality of the patient-derived iPSC lines were confirmed, and the correction of the target mutation fully restored the capability of encoding Prominin-1 (CD133) in the genetically repaired patient-derived iPSC lines. CONCLUSIONS: The c.1354dupT mutation in the PROM1 gene is associated to three distinct AR phenotypes of IRD. This pleotropic effect might be related to the influence of monoallelic variants in other genes associated with retinal dystrophies. However, further evidence needs to be provided. Future experiments should include gene-edited patient-derived iPSC due to its potential as disease modelling tools to elucidate this matter in question.

Does PLEX® Elite 9000 OCT Identify and Characterize Most Posterior Pole Lesions in Highly Myopic Patients?

High myopia (HM) is defined as an axial length (AL) ≥ 26 mm that may result in various pathologies that constitute pathologic myopia (PM). The PLEX® Elite 9000 (Carl Zeiss AC, Jena, Germany) is a new swept-source optical coherence tomography (SS-OCT) underdevelopment that allows wider, deeper and more detailed posterior-segment visualization; it can acquire ultra-wide OCT angiography (OCTA) or new ultra-wide high-density scans in one image. We assessed the technology's ability to identify/characterize/quantify staphylomas and posterior pole lesions or image biomarkers in highly myopic Spanish patients and estimate the technology's potential to detect macular pathology. The instrument acquired 6 × 6 OCTA, 12 × 12 or 6 × 6 OCT cubes, and at least two high-definition spotlight single scans. A hundred consecutive patients (179 eyes; age, 51.4 ± 16.8 years; AL, 28.8 ± 2.33 mm) were recruited in one center for this prospective observational study. Six eyes were excluded because images were not acquired. The most common alterations were perforating scleral vessels (88.8%), classifiable staphyloma (68.7%), vascular folds (43%), extrafoveal retinoschisis (24%), dome-shaped macula (15.6%), and more uncommonly, scleral dehiscence (4.46%), intrachoroidal cavitation (3.35%), and macular pit (2.2%). The retinal thickness of these patients decreased, and the foveal avascular zone increased in the superficial plexus compared with normal eyes. SS-OCT is a novel potent tool that can detect most main posterior pole complications in PM and may provide us with a better understanding of the associated pathologies; some pathologies were identifiable only with this new kind of equipment, such as perforating scleral vessels, which seem to be the most common finding and not so frequently related to choroidal neovascularization, as previously reported.

Ala®sil chemical characterization and toxicity evaluation: an example of the need for the Medical Device Regulation 2017/745.

Introduction: Ala®sil infusion was on the market for clinical use under the Medical Devices Directive (MDD) 93/42/EEC as an irrigating solution based on polydimethylsiloxane (PDMS). The product was withdrawn in 2016, and to the best of our knowledge, it did not cause any health damage. Methods: A bibliographic review and experimental analysis were conducted to evaluate whether this CE-marked product could have been used in patients under the current Medical Device Regulation (MDR) 2017/745. Analytical results from gas chromatography-mass spectrometry (GC-MS) and matrixassisted laser desorption ionization (MALDI) were performed. Citotoxicity studies were also carried out. Results: Only one study related to Ala®sil clinical use was found, describing a pilot series of five patients. The authors rated the product as not helpful in three out of the five cases for internal searching of retinal breaks and in four out of the five cases for drainage of subretinal fluid. No other scientific papers or documentation was found regarding Ala®sil's safety. Nevertheless, the product was introduced in the market after achieving the CE marking. GC-MS and MALDI showed that the polymer has a low molecular weight of 1,000 g/mol. Several linear and cyclic low-molecular-weight components (LMWCs) were identified as impurities ranging from L3 to D8, with a molecular weight below 600 g/mol. The Ala®sil sample was found to be cytotoxic after 24 h of cell culture but non-cytotoxic after 72 h, probably due to the cellular regeneration capacity of an immortalized cell line. Tissular cytotoxicity revealed an increased apoptosis rate but without morphological modifications. Discussion: Although Ala®sil cannot be classified as cytotoxic, this substance appears to increase retinal cell death processes. This study supports the notion that the MDDwas not functioning adequately to ensure the safety of medical devices. However, the current MDR 2017/745 imposes stricter standards to prevent the commercialization of medical devices without high-quality preclinical and clinical information, as well as precise clinical verification for their use, information not available for Ala®sil infusion.

Intravitreal allogeneic mesenchymal stem cells: a non-randomized phase II clinical trial for acute non-arteritic optic neuropathy.

BACKGROUND: An effective treatment for acute non-arteritic ischemic optic neuropathy (NA-AION) has not been known or proven yet. Previous studies have suggested a neuroprotective effect of allogeneic bone marrow-derived mesenchymal stem cells. This study aims to report the results of a clinical trial on patients with acute non-arteritic optic neuropathy (NA-AION) treated with an intravitreal injection of allogeneic bone marrow-derived mesenchymal stem cells (BM-MSCs) (MSV®). METHODS: We conducted a prospective, non-randomized, clinical phase-II study (Eudra CT number 2016-003029-40; ClinicalTrials.gov Registry NCT03173638) that included 5 patients with acute unilateral NA-AION diagnosed within 2 weeks after symptom onset and who received an intravitreal injection of allogeneic BM-MSCs (0.05 ml; cell concentration: 1.5 × 106cells/mL). The patients underwent regular ophthalmological examinations and were followed for one year. RESULTS: In this trial, allogeneic BM-MSCs appeared to be safe as no patients developed signs of acute nor chronic intraocular inflammation or a significant change in intraocular pressure, although an epiretinal membrane was developed in one patient. A retrolental aggregate formed shortly after the injection spontaneously disappeared within a few weeks in another phakic patient, leaving a subcapsular cataract. Visual improvement was noted in 4 patients, and amplitudes of P100 on the visually evoked potentials recordings increased in three patients. The retinal nerve fiber layer and macular ganglion cell layer thicknesses significantly decreased during the follow-up. CONCLUSIONS: Besides the development of an epiretinal membrane in one patient, the intravitreal application of allogeneic BM-MSCs appeared to be intraocularly well tolerated. Consequently, not only NA-AION but also BM-MSCs deserve more clinical investigational resources and a larger randomized multicenter trial that would provide stronger evidence both about safety and the potential therapeutic efficacy of intravitreally injected allogeneic BM-MSCs in acute NA-AION. TRIAL REGISTRATION: Safety Assessment of Intravitreal Mesenchymal Stem Cells for Acute Non-Arteritic Anterior Ischemic Optic Neuropathy (NEUROSTEM). NCT03173638. Registered June 02, 2017 https://clinicaltrials.gov/ct2/show/NCT03173638 .

Impact of COVID-19 Confinement on Quality of Life of Patients with Age-Related Macular Degeneration: A Two-Wave Panel Study.

Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries. Intravitreal injections of antiangiogenic agents (anti-VEGF) can stop vision loss in the neovascular form of the disease (nAMD). The aim of this study was to assess the general health-related quality of life (HRQoL) in a cohort of patients with nAMD treated with intravitreal anti-VEGF injections and to detesrmine to what extent their HRQoL was affected by COVID-19. This was an observational, analytical, and longitudinal study performed with a two-wave panel survey. Clinical outcomes, HRQoL, and tangible support were evaluated. In the final survey, changes in living conditions and medical visits due to the COVID-19 pandemic were also examined. Of the 102 patients initially interviewed in the before-COVID survey, 24 were lost after 30 months of follow-up. In the initial assessment, the mean health index was 0.73 ± 0.2. The EQ VAS score worsened at the final survey (p = 0.048). Patients needing treatment in both eyes (p = 0.007) and with lower levels of bilateral visual acuity (p = 0.018) reported an increase in social support at the final survey. In conclusion, patients perceived a worsening in HRQoL after confinement. However, patients enjoyed good social support that improved in the after-COVID survey.

Modifiable Determinants of Satisfaction with Intravitreal Treatment in Patients with Neovascular Age-Related Macular Degeneration.

BACKGROUND: The success of intravitreal treatment for neovascular age-related macular degeneration (nAMD) depends on maximal adherence to treatment, which in turn requires patient satisfaction. OBJECTIVE: The aim of this study was to assess the factors associated with nAMD patient satisfaction to implement actions to improve treatment experiences and increase adherence. DESIGN: This was a prospective, observational, analytical, cross-sectional study. SUBJECTS: Our study included 100 consecutive nAMD patients under intravitreal treatment for at least 1 year. METHODS: Patients completed the Macular Disease Treatment Satisfaction Questionnaire (MacTSQ) and the EuroQol Visual Analog Scale (EQ VAS). A logistic regression was estimated to model the low values of the satisfaction score (MacTSQ < 50). RESULTS: The mean age of patients was 82.1 ± 7.8 years and 62% were female. Males (p = 0.002) and patients who improved their visual acuity (p = 0.004) were more satisfied, while patients who received a higher number of injections (p = 0.036) and treatment in both eyes (p = 0.001) were less satisfied. Higher health-related quality of life was related to higher satisfaction. The sensitivity and specificity of the predictive model were 75.8% and 76.1%, respectively. Factors independently associated with low satisfaction were female sex (odds ratio [OR] 6.84), going to the clinic alone (OR 8.51), longer duration of treatment (OR 0.62), receiving treatment in both eyes (OR 3.54), and suffering a decline in visual acuity (OR 3.30). The questionnaire revealed patients' needs for more information and injection points closer to their homes. CONCLUSIONS: Well-defined areas for improvement were identified, i.e. to improve the information offered to each patient, to incorporate new long-acting drugs, and to establish locations for injection services in peripheral areas.

Cell Replacement Therapy for Retinal and Optic Nerve Diseases: Cell Sources, Clinical Trials and Challenges.

The aim of this review was to provide an update on the potential of cell therapies to restore or replace damaged and/or lost cells in retinal degenerative and optic nerve diseases, describing the available cell sources and the challenges involved in such treatments when these techniques are applied in real clinical practice. Sources include human fetal retinal stem cells, allogenic cadaveric human cells, adult hippocampal neural stem cells, human CNS stem cells, ciliary pigmented epithelial cells, limbal stem cells, retinal progenitor cells (RPCs), human pluripotent stem cells (PSCs) (including both human embryonic stem cells (ESCs) and human induced pluripotent stem cells (iPSCs)) and mesenchymal stem cells (MSCs). Of these, RPCs, PSCs and MSCs have already entered early-stage clinical trials since they can all differentiate into RPE, photoreceptors or ganglion cells, and have demonstrated safety, while showing some indicators of efficacy. Stem/progenitor cell therapies for retinal diseases still have some drawbacks, such as the inhibition of proliferation and/or differentiation in vitro (with the exception of RPE) and the limited long-term survival and functioning of grafts in vivo. Some other issues remain to be solved concerning the clinical translation of cell-based therapy, including (1) the ability to enrich for specific retinal subtypes; (2) cell survival; (3) cell delivery, which may need to incorporate a scaffold to induce correct cell polarization, which increases the size of the retinotomy in surgery and, therefore, the chance of severe complications; (4) the need to induce a localized retinal detachment to perform the subretinal placement of the transplanted cell; (5) the evaluation of the risk of tumor formation caused by the undifferentiated stem cells and prolific progenitor cells. Despite these challenges, stem/progenitor cells represent the most promising strategy for retinal and optic nerve disease treatment in the near future, and therapeutics assisted by gene techniques, neuroprotective compounds and artificial devices can be applied to fulfil clinical needs.

Descriptive Study of a Cohort of 488 Patients with Inherited Retinal Dystrophies.

PURPOSE: To analyze the distribution of inherited retinal diseases (IRDs), describe the clinical characteristics of patients, and determine the percentages of patients with genetic diagnosis in the Castilla y Leon region of Spain. METHODS: All patients with an IRD seen in the two major referral units of Castilla y Leon during a 20-year period were included. The ages at symptom onset, diagnosis, and the last visit; sex; family history; history of consanguinity; type of inheritance; status of the fundus and electroretinogram findings; lens and macular status, visual acuity; and visual field data were recorded. Patients were divided into those with retinitis pigmentosa (RP) and all others. Gene mutations were gathered when available. RESULTS: Four hundred eighty-eight patients with IRDs were studied: 216 (44.26%) with RP of which 34 (15.74%) had syndromic diseases, and 272 had other conditions being 161 (59,19%) macular dystrophies. The mean delay in diagnosis was 6-16.2 years respectively. For the RP group the mean age at the last visit was 47.96±17,26; mean age of cataract surgery was 48.30 ± 12.01 years; and the foveal area was preserved in 74 (35.07%) patients, atrophic in 101 (47.87%), and edematous in 36 (17.06%). A genetic study had been performed in 58 (26.85%) of patients with RP and 71 (26,1%) of the rest, being indeterminate in 17 (29.31%) out of RP group and 20 (28.16%) out of the others. CONCLUSION: Clinical characteristics are comparable to other published series. There is a significant delay in diagnosis. The number of patients with IRDs and available genetic diagnosis, thus being possible candidates for undergoing personalized treatments including gene therapy in our region is low and must be improved.

Phenotypic Differences in a PRPH2 Mutation in Members of the Same Family Assessed with OCT and OCTA.

Choroidal dystrophies comprise a group of chorioretinal degenerations. However, the different findings observed among these patients make it difficult to establish a correct clinical diagnosis. The objective of this study was to characterize new clinical findings by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in these patients. Four family members with a PRPH2 gene mutation (p.Arg195Leu) were included. OCT was performed at the macula, and the thickness of the outer and inner retina, total retina, and choroid was measured. The features of the vascular network were analyzed by OCTA. Patients showed a decreased outer nuclear layer in the avascular area compared with the controls. Two patients presented greater foveal and parafoveal degeneration of the outer retina, whereas the most degenerated area in the rest was the perifovea. Disruption of the third outer band at the foveola is one of the first-altered outer bands. Slow blood flow areas or capillary dropout were main signs in the deep capillary plexus. Microaneurysms were frequently observed in less degenerated retinas. Vascular loops and intraretinal microvascular abnormalities (IRMAs) were present in the superficial plexus. Extensive degeneration of the choriocapillaris was detected. Phenotypic differences were found between patients: two showed central areolar choroidal dystrophy and the rest had extensive chorioretinal atrophy. These signs observed in OCT and OCTA can help to more appropriately define the clinical disease in patients with choroidal dystrophies.

Long-term visual pathway alterations after elemental mercury poisoning: report of a series of 29 cases.

BACKGROUND: There are few clinical data on retinal involvement after acute exposure to high concentrations mercury and the available reports are based on a small number of patients suffering chronic exposure. The purpose of this paper is to report findings in workers acutely exposed to very high concentrations of mercury vapor with the aim of providing data on a possible direct retinal involvement. METHODS: Twenty-nine patients and 16 controls were evaluated in a comparative case series. Mercury levels in blood and urine samples, visual acuity (VA), contrast sensitivity (CS), visual field (VF), color discrimination and optical coherence tomography (OCT) were recorded. The pattern reversal visual-evoked potentials (PRVEP), full-field and multifocal electroretinography (ffERG/mfERG), pattern electroretinography (PERG), systemic symptoms, presence of erethism, and electromyography (EMG) were also gathered. A descriptive analysis was performed. The correlations between variables also were studied. In addition, electrophysiological data from those patients with deeper VF defects (group 1) were compared with a normal control group. RESULTS: Twenty-six workers exhibited symptoms of erethism. The EMG showed sensorimotor polyneuropathy and multiple mononeuropathy. The VA was slightly affected in 48.27% (n = 14) of subjects. Loss of CS in at least one of four spatial frequencies and color vision alterations occurred in 96.5% (n = 28) and 44.8% (n = 13), respectively. VF alterations were identified in 72.4% (n = 21) patients. No morphologic changes were seen in the OCT scans. Latencies over 100 milliseconds and reduced amplitudes of P100 were found in the PRVEP (p < 0.05). The reduced amplitude of the b wave at the ffERG, of the P50 at the PERG and of the P1 wave at the mfERG results (p < 0.05) suggested that the outer retina was involved. Significant negative correlations among blood mercury levels, VA, and ffERG were observed. CONCLUSIONS: In this case series, showed that acute exposure to mercury vapor had a hazardous effect on the visual system. Although neurologic and visual pathway involvement was clearly demonstrated, the differences found compared to control support the existence of a direct functional retinal damage and participation in impaired vision in mercury poisoning.

Intraocular toxicity caused by MEROCTANE perfluorocarbon liquid.

Serious intraocular toxicity cases have been reported worldwide after the use of different perfluorocarbon liquids. The current study reports for the first-time the clinical pictures of cases of acute intraocular toxicity caused by MEROCTANE, a perfluoro-octane commercialized by a Turkish company and distributed in many countries. A series of 18 cases from Chile and Spain was retrospectively analysed. To evaluate the impurity profile, a suspicious MEROCTANE sample (lot OCT.01.2013) was analysed by gas chromatography mass spectrometry and compared with a non-suspicious sample of the same commercial perfluoro-octane (lot OCT 722011). Cytotoxicity was tested following a direct-contact method, taking into consideration the high volatility and hydrophobicity of perfluoro-octane and following the ISO 10993 guideline. Cytotoxicity test showed clear cytotoxic effects of the analysed batch (less than 9% of cell viability). Moreover, chemical analysis demonstrated the presence of many contaminants, some highly toxic (acids and alcohols). Perfluorocarbon liquids are useful tools for intraocular surgery but companies and Agencies of Medical Devices must implement measures that guarantee the safety of these products based on both chemical and cytotoxicity analysis for every batch. Medical staff should be encouraged to report any suspected case to their respective National Agencies.

Early Detection of Incipient Retinal Pigment Epithelium Atrophy Overlying Drusen with Fundus Autofluorescence vs. Spectral Domain Optical Coherence Tomography.

PURPOSE: This study aims to find out which tool, fundus autofluorescence (FAF) or spectral domain optical coherence tomography (SD-OCT), is more sensitive in detecting retinal pigment epithelium (RPE) demise overlying drusen and can, therefore, help predict geographic atrophy (GA) appearance in Age-Related Macular Degeneration (AMD). METHODS: A single-site, retrospective, observational, longitudinal study was conducted. Patients with intermediate AMD (iAMD) (large (>125 µm) or intermediate (63-125 µm) drusen with hyper/hypopigmentation) with a minimum follow-up of 18 months were included. Drusen with overlying incipient RPE atrophy were identified on SD-OCT defined as choroidal hypertransmission or nascent geographic atrophy (nGA). These selected drusen were, then, traced backwards in time to determine if incipient RPE atrophy overlying drusen was observed on FAF (well-demarcated region of absence of autofluorescence) before, simultaneously, or after having detected the first signs of incipient RPE atrophy on SD-OCT. The number of drusen in which signs of incipient RPE atrophy was detected earlier using FAF or SD-OCT was compared. The time elapsed from the identification with the more sensitive method to the other was recorded and analyzed. RESULTS: One hundred and thirty-three drusen in 22 eyes of 22 patients were included. Of these, 112 (84.2%) drusen showed choroidal hypertransmission and 21(15.8%) nGA. Early signs of atrophy overlying drusen were found simultaneously on SD-OCT and FAF in 52 cases (39.1%, 95% CI 30.8-47.9%), earliest on FAF in 51 (38.3%, 95% CI 30.0-47.2%) and first on SD-OCT in 30 (22.6%, 95% CI 15.8-30.6%; p < 0.05). Statistically significant differences were found between both techniques (p=0.005), with FAF detecting it earlier than SD-OCT. When RPE atrophy was found first on FAF, the median time to diagnosis with SD-OCT was 6.6 months (95% CI 5.5 to 8.6), while if detection occurred earlier on SD-OCT, the median time until identification with FAF was 12.6 months (95% CI 6.0 to 23.4; p=0.0003). CONCLUSIONS: In iAMD cases in which early atrophy overlying drusen is not detected simultaneously in FAF and SD-OCT, FAF was significantly more sensitive. Nevertheless, a multimodal approach is recommended and required to evaluate these patients.

Reliability of colour perimetry to assess macular pigment optical density in age-related macular degeneration.

BACKGROUND: The aim of this study was to determine the intra-session repeatability and inter-examiner reproducibility of the colour perimetry technique when assessing in vivo macular pigment optical density in age-related macular degeneration patients. METHODS: Age-related macular degeneration patients were classified into four groups: early age-related macular degeneration, intermediate age-related macular degeneration, atrophic age-related macular degeneration and neovascular age-related macular degeneration after undergoing fundus photography (TRC 50DX type IA) and spectral-domain optical coherence tomography analysis (Topcon 3D-2000). Central fixation was confirmed in all patients using the MP-1 microperimeter (Nidek, Padua, Italy). To analyse repeatability, one examiner obtained three consecutive macular pigment optical density measures with MonCV3 device (Metrovision, Perenchies, France). To study agreement between two observers, a second examiner performed another macular pigment optical density measurement in random order. Within-subject standard deviation, coefficient of variation, and intraclass correlation coefficient data were obtained. RESULTS: Fifty two (32 females and 20 males) consecutive age-related macular degeneration patients having a mean age of 71.5 ± 8.2 years were recruited. Six had early age-related macular degeneration, 25 had intermediate age-related macular degeneration, 10 had atrophic age-related macular degeneration and 11 had neovascular age-related macular degeneration. For repeatability, coefficient of variation values ranged from 22.3% (neovascular age-related macular degeneration) to 41.0% (atrophic age-related macular degeneration) and intraclass correlation coefficient values from 0.52 (intermediate age-related macular degeneration) to 0.79 (neovascular age-related macular degeneration). For agreement between two examiners, coefficient of variation values ranged from 20.1% (intermediate age-related macular degeneration) to 37.8% (neovascular age-related macular degeneration) and intraclass correlation coefficient values from 0.61 (neovascular age-related macular degeneration) to 0.80 (atrophic age-related macular degeneration). CONCLUSION: The reliability (intra-session repeatability and inter-examiner reproducibility) of colour perimetry technique to assess macular pigment optical density in age-related macular degeneration patients is only moderate. Thus, it cannot be recommended to be performed when evaluating and monitoring age-related macular degeneration patients in the daily clinic.