Multimodal Imaging-Guided Stem Cell Ocular Treatment.

Stem cell therapies are gaining traction as promising treatments for a variety of degenerative conditions. Both clinical and preclinical studies of regenerative medicine are hampered by the lack of technologies that can evaluate the migration and behavior of stem cells post-transplantation. This study proposes an innovative method to longitudinally image in vivo human-induced pluripotent stem cells differentiated to retinal pigment epithelium (hiPSC-RPE) cells by multimodal photoacoustic microscopy, optical coherence tomography, and fluorescence imaging powered by ultraminiature chain-like gold nanoparticle cluster (GNC) nanosensors. The GNC exhibits an optical absorption peak in the near-infrared regime, and the 7-8 nm size in diameter after disassembly enables renal excretion and improved safety as well as biocompatibility. In a clinically relevant rabbit model, GNC-labeled hiPSC-RPE cells migrated to RPE degeneration areas and regenerated damaged tissues. The hiPSC-RPE cells' distribution and migration were noninvasively, longitudinally monitored for 6 months with exceptional sensitivity and spatial resolution. This advanced platform for cellular imaging has the potential to enhance regenerative cell-based therapies.

Autoantibodies Against Bestrophin in Non-Paraneoplastic Acute Exudative Polymorphous Vitelliform Maculopathy.

Acute exudative polymorphous vitelliform maculopathy (AEPVM) has recently been identified as a paraneoplastic manifestation of various cancers. Yet, the first reported cases of AEPVM in the literature were reported in seemingly healthy individuals. It is not clear whether those individuals harbored unidentified mutations or occult cancers, or truly represented a separate subset of AEPVM. Here, we report two cases of mutation-negative, autoantibody-positive non-paraneoplastic AEPVM. We present multimodal ocular imaging to demonstrate the presentation of this subset of AEPVM. [Ophthalmic Surg Lasers Imaging Retina 2024;55:51-54.].

Local progression kinetics of macular atrophy in recessive Stargardt disease.

BACKGROUND: To determine the effect of lesion topography on progression in Stargardt disease (STGD1). METHODS: Fundus autofluoresence (excitation 488 nm) images of 193 eyes in patients with proven ABCA4 mutation were semi-automatically segmented for autofluoresence changes: (DDAF) and questionably decreased autofluoresence (QDAF), which are proxies for retinal pigment epithelial (RPE) atrophy. We calculated topographic incidence of DDAF and DDAF + QDAF, as well as velocity of progression of the border of lesions using Euclidean distance mapping. RESULTS: Incidence of atrophy was highest near the fovea, then decreased in incidence with increased foveal eccentricity. However, the rate of atrophy progression followed the opposite pattern; rate of atrophy increased with distance from foveal center. The mean growth rate 500 microns from the foveal center for DDAF + QDAF was 39 microns per year (95% CI = 28-49), whereas the mean growth rate 3000 microns from the foveal center was 342 microns per year (95% CI = 194-522). No difference in growth rate was noted by axis around the fovea. CONCLUSIONS: Incidence and progression of atrophy by fundus autofluorescence follow opposite patterns in STGD1. Further, atrophy progression increases significantly with distance from foveal center, which should be taken into consideration in clinical trials.

Static Perimetry in the Rate of Progression in USH2A-related Retinal Degeneration (RUSH2A) Study: Assessment Through 2 Years.

PURPOSE: To evaluate disease progression using static perimetry (SP) in patients with USH2A-related retinal degeneration, including Usher syndrome type 2 (USH2) and nonsyndromic autosomal recessive retinitis pigmentosa. DESIGN: Prospective, observational cohort study. METHODS: A total of 102 patients with biallelic disease-causing sequence variants in USH2A with baseline best-corrected visual acuity (BCVA) letter score ≥54 were recruited from 16 clinical sites in Europe and North America. SP, BCVA, full-field stimulus thresholds, spectral domain optical coherence tomography macular scans, and fundus-guided mesopic microperimetry were performed at baseline and annually. The main outcome measures were total hill of vision (VTOT), hill of vision in the central 30° (V30), VTOT minus V30 (VPERIPH), and mean sensitivity. RESULTS: The average decline (95% CI) was 2.05 (1.40, 2.70) decibel-steradian (dB-sr)/y for VTOT, 0.48 (0.32, 0.65) dB-sr/y for V30, 1.53 (0.97, 2.08) dB-sr/y for VPERIPH, and 0.55 (0.40, 0.71) dB/y for mean sensitivity. Average percentage decline per year was 8.3 (5.5, 11.1) for VTOT, 5.2 (3.0, 7.4) for V30, 16.0 (9.5, 22.0) for VPERIPH, and 5.1 (3.5, 6.7) for mean sensitivity. Changes from baseline to year 2 in all SP measures were highly correlated (r's ranging from 0.52 [V30 vs VPERIPH] to 0.98 [VTOT vs VPERIPH]). CONCLUSIONS: Quantitative measures of SP declined significantly over 2 years in USH2A-related retinal degeneration. The annual percentage rate of change was greatest for VTOT and VPERIPH, whereas V30 and mean sensitivity changed least, reflecting earlier and more severe peripheral degeneration compared with central loss.

Clinical and imaging findings of choroideremia in a pediatric patient due to a novel frameshift mutation.

Purpose: To describe the clinical characteristics, imaging findings and genetic testing results of a young simplex male with choroideremia. Observations: A 6-year-old Hispanic-Chinese male was referred to the retina clinic for peripheral retinal pigmentary changes observed in both eyes on routine exam. The patient has an unremarkable family history and developmental history. Best corrected visual acuity was 20/25 in both eyes. Optical coherence tomography demonstrated attenuation of the ellipsoid and interdigitation zones. Widefield fundus autofluorescence demonstrated nummular hypo-autofluorescence peripherally in both eyes. Genetic testing revealed a variant originally described as a variant of uncertain significance (VUS) a c. 1775_1814del (p.Glu592Valfs*44) identified in the CHM gene, which was reclassified as pathogenic following segregation analysis. The patient was diagnosed with choroideremia due to a CHM pathogenic variant. Conclusions: The multimodal imaging findings demonstrated here illustrate important clues to the diagnosis of Choroideremia in a simplex male.

Baseline Microperimetry and OCT in the RUSH2A Study: Structure-Function Association and Correlation With Disease Severity.

PURPOSE: To investigate baseline mesopic microperimetry (MP) and spectral domain optical coherence tomography (OCT) in the Rate of Progression in USH2A-related Retinal Degeneration (RUSH2A) study. DESIGN: Natural history study METHODS: Setting: 16 clinical sites in Europe and North AmericaStudy Population: Participants with Usher syndrome type 2 (USH2) (N = 80) or autosomal recessive nonsyndromic RP (ARRP) (N = 47) associated with biallelic disease-causing sequence variants in USH2AObservation Procedures: General linear models were used to assess characteristics including disease duration, MP mean sensitivity and OCT intact ellipsoid zone (EZ) area. The associations between mean sensitivity and EZ area with other measures, including best corrected visual acuity (BCVA) and central subfield thickness (CST) within the central 1 mm, were assessed using Spearman correlation coefficients. MAIN OUTCOME MEASURES: Mean sensitivity on MP; EZ area and CST on OCT. RESULTS: All participants (N = 127) had OCT, while MP was obtained at selected sites (N = 93). Participants with Usher syndrome type 2 (USH2, N = 80) and nonsyndromic autosomal recessive Retinitis Pigmentosa (ARRP, N = 47) had the following similar measurements: EZ area (median (interquartile range [IQR]): 1.4 (0.4, 3.1) mm2 vs 2.3 (0.7, 5.7) mm2) and CST (median (IQR): 247 (223, 280) µm vs 261 (246, 288), and mean sensitivity (median (IQR): 3.5 (2.1, 8.4) dB vs 5.1 (2.9, 9.0) dB). Longer disease duration was associated with smaller EZ area (P < 0.001) and lower mean sensitivity (P = 0.01). Better BCVA, larger EZ area, and larger CST were correlated with greater mean sensitivity (r > 0.3 and P < 0.01). Better BCVA and larger CST were associated with larger EZ area (r > 0.6 and P < 0.001). CONCLUSIONS: Longer disease duration correlated with more severe retinal structure and function abnormalities, and there were associations between MP and OCT metrics. Monitoring changes in retinal structure-function relationships during disease progression will provide important insights into disease mechanism in USH2A-related retinal degeneration.

Oxidative stress differentially impacts apical and basolateral secretion of angiogenic factors from human iPSC-derived retinal pigment epithelium cells.

The retinal pigment epithelium (RPE) is a polarized monolayer that secretes growth factors and cytokines towards the retina apically and the choroid basolaterally. Numerous RPE secreted proteins have been linked to the pathogenesis of age-related macular degeneration (AMD). The purpose of this study was to determine the differential apical and basolateral secretome of RPE cells, and the effects of oxidative stress on directional secretion of proteins linked to AMD and angiogenesis. Tandem mass tag spectrometry was used to profile proteins in human iPSC-RPE apical and basolateral conditioned media. Changes in secretion after oxidative stress induced by H2O2 or tert-butyl hydroperoxide (tBH) were investigated by ELISA and western analysis. Out of 926 differentially secreted proteins, 890 (96%) were more apical. Oxidative stress altered the secretion of multiple factors implicated in AMD and neovascularization and promoted a pro-angiogenic microenvironment by increasing the secretion of pro-angiogenic molecules (VEGF, PTN, and CRYAB) and decreasing the secretion of anti-angiogenic molecules (PEDF and CFH). Apical secretion was impacted more than basolateral for PEDF, CRYAB and CFH, while basolateral secretion was impacted more for VEGF, which may have implications for choroidal neovascularization. This study lays a foundation for investigations of dysfunctional RPE polarized protein secretion in AMD and other chorioretinal degenerative disorders.

Automated Segmentation of Autofluorescence Lesions in Stargardt Disease.

OBJECTIVE: To train a deep learning (DL) algorithm to perform fully automated semantic segmentation of multiple autofluorescence lesion types in Stargardt disease. DESIGN: Cross-sectional study with retrospective imaging data. SUBJECTS: The study included 193 images from 193 eyes of 97 patients with Stargardt disease. METHODS: Fundus autofluorescence images obtained from patient visits between 2013 and 2020 were annotated with ground-truth labels. Model training and evaluation were performed using fivefold cross-validation. MAIN OUTCOMES MEASURES: Dice similarity coefficients, intraclass correlation coefficients, and Bland-Altman analyses comparing algorithm-predicted and grader-labeled segmentations. RESULTS: The overall Dice similarity coefficient across all lesion classes was 0.78 (95% confidence interval [CI], 0.69-0.86). Dice coefficients were 0.90 (95% CI, 0.85-0.94) for areas of definitely decreased autofluorescence (DDAF), 0.55 (95% CI, 0.35-0.76) for areas of questionably decreased autofluorescence (QDAF), and 0.88 (95% CI, 0.73-1.00) for areas of abnormal background autofluorescence (ABAF). Intraclass correlation coefficients comparing the ground-truth and automated methods were 0.997 (95% CI, 0.996-0.998) for DDAF, 0.863 (95% CI, 0.823-0.895) for QDAF, and 0.974 (95% CI, 0.966-0.980) for ABAF. CONCLUSIONS: A DL algorithm performed accurate segmentation of autofluorescence lesions in Stargardt disease, demonstrating the feasibility of fully automated segmentation as an alternative to manual or semiautomated labeling methods.

Real-world outcomes of voretigene neparvovec treatment in pediatric patients with RPE65-associated Leber congenital amaurosis.

PURPOSE: To investigate real-world safety and efficacy of voretigene neparvovec gene therapy administration in pediatric patients with biallelic RPE65 disease-causing variants. METHODS: A retrospective study of 27 eyes of 14 patients with RPE65-associated Leber congenital amaurosis examined postoperative complications and longitudinal changes in photoreceptor function following treatment with subretinal injection of voretigene neparvovec. Full-field stimulus threshold testing (FST), Goldmann visual fields (GVF), best-corrected visual acuity (BCVA), and central subfield thickness (CST) on optical coherence tomography (OCT) scans were collected preoperatively and up to 12 months posttreatment. RESULTS: Baseline through 6-12 month follow-up FST and GVF data were obtained for 13 eyes of 7 patients. FST improved for each eye after treatment with a mean improvement of 2.1 log-units (P < 0.001) and GVF improved for each eye with a mean improvement of 221 sum degrees (P < 0.001). BCVA improved from logMAR 0.98 at baseline to logMAR 0.83 at last follow-up (P < 0.001). Across 19 eyes of 10 patients included in CST analysis, there was a small but statistically significant 9-µ decrease in mean CST from baseline to last follow-up (P < 0.001). The most common postoperative issues included elevation in intraocular pressure (59%), persistent intraocular inflammation (15%), and vitreous opacities (26%) that resolved over a period of months. CONCLUSIONS: This report provides some of the earliest longitudinal real-world evidence of the pediatric safety and efficacy of voretigene neparvovec using multiple functional and structural measures of the retina. Outcomes demonstrate significant improvements in visual function consistent with clinical trial results.

Characterization of the Spectrum of Ophthalmic Changes in Patients With Alagille Syndrome.

Purpose: The purpose of this study was to characterize the phenotypic spectrum of ophthalmic findings in patients with Alagille syndrome. Methods: We conducted a retrospective, observational, multicenter, study on 46 eyes of 23 subjects with Alagille syndrome. We reviewed systemic and ophthalmologic data extracted from medical records, color fundus photography, fundus autofluorescence, optical coherence tomography, visual fields, electrophysiological assessments, and molecular genetic findings. Results: Cardiovascular abnormalities were found in 83% of all cases (of those, 74% had cardiac murmur), whereas 61% had a positive history of hepatobiliary issues, and musculoskeletal anomalies were present in 61% of all patients. Dysmorphic facies were present in 16 patients, with a broad forehead being the most frequent feature. Ocular symptoms were found in 91%, with peripheral vision loss being the most frequent complaint. Median (range) Snellen visual acuity of all eyes was 20/25 (20/20 to hand motion [HM]). Anterior segment abnormalities were present in 74% of the patients; of those, posterior embryotoxon was the most frequent finding. Abnormalities of the optic disc were found in 52%, and peripheral retinal abnormalities were the most frequent ocular finding in this series, found in 96% of all patients. Fifteen JAG1 mutations were identified in 16 individuals; of those, 6 were novel. Conclusions: This study reports a cohort of patients with Alagille syndrome in which peripheral chorioretinal changes were more frequent than posterior embryotoxon, the most frequent ocular finding according to a number of previous studies. We propose that these peripheral chorioretinal changes are a new hallmark to help diagnose this syndrome.

Association of No-Cost Genetic Testing Program Implementation and Patient Characteristics With Access to Genetic Testing for Inherited Retinal Degenerations.

IMPORTANCE: The benefits of no-cost genetic testing initiatives have not been characterized. The no-cost My Retina Tracker Genetic Testing Study (MRT-GTS) research registry for inherited retinal degenerations (IRDs) was launched in 2017 in the US. OBJECTIVE: To investigate the associations of MRT-GTS implementation and patient characteristics with access to genetic testing for IRDs. DESIGN, SETTING, AND PARTICIPANTS: In a cross-sectional design, analysis of new patients evaluated 12 months before (July 1, 2016, to June 13, 2017) and 12 months after (June 14, 2017, to June 30, 2018) MRT-GTS implementation at a single academic referral eye center was conducted. Participants included 369 patients with IRD. Data analysis was conducted from February to June 2020. MAIN OUTCOMES AND MEASURES: Change in rates of successfully obtaining genetic testing, odds ratios (ORs) of association between patient characteristics and obtaining testing, and days elapsed from clinic visit to reporting of results. RESULTS: Among 369 patients (mean [SD] age, 39.5 [20.8] years; 193 [52.3%] women), 144 were evaluated in the pre-MRT-GTS period and 225 in the post-MRT-GTS period. The baseline rate of successfully obtaining testing was 51.4% (95% CI, 42.6%-60.2%). The initiation of MRT-GTS was associated with a 28.9-percentage point increase in testing rate (95% CI, 16.7%-41.1%; P < .001). Patient characteristics that increased the odds of obtaining testing were eligibility for MRT-GTS (OR, 14.15; 95% CI, 7.36-27.24; P < .001) and worse visual acuity (logMAR +1.0; Snellen equivalent decrease from 20/20 to 20/200) in the better-seeing eye (OR, 1.92; 95% CI, 1.27-2.91; P < .01). Patients had decreased odds when identifying as Black or African American (OR, 0.10; 95% CI, 0.04-0.24; P < .001) or other race (OR, 0.37; 95% CI, 0.15-0.91; P = .03) compared with White race, and when the primary language was not English (OR, 0.13; 95% CI, 0.03-0.55; P < .01). The proportion of test results reported within 90 days was 81.5% (95% CI, 74.8%-86.4%) when eligible for MRT-GTS compared with 48.1% (95% CI, 35.6%-58.1%) when not eligible (P < .001). CONCLUSIONS AND RELEVANCE: In this study, the implementation of MRT-GTS was associated with an increase in the proportion of patients who successfully obtained testing, suggesting the potential clinical value of this approach. Patient-level demographic and clinical factors appear to be associated with decisions to pursue testing.

The Michigan Retinal Degeneration Questionnaire: A Patient-Reported Outcome Instrument for Inherited Retinal Degenerations.

PURPOSE: To create a psychometrically validated patient-reported outcome measure for inherited retinal degenerations. DESIGN: Qualitative and quantitative patient-reported outcome (PROs) questionnaire development using item response theory validation. METHODS: One hundred twenty-eight patients with a diagnosis of an inherited retinal degeneration at the Kellogg Eye Center (University of Michigan) were recruited and administered a 166-item questionnaire comprising 7 expert-defined domains. The questionnaire was re-administered 4-16 days later to a subset of 25 participants to assess test-retest variability. Graded response models were fit by Cai's Metropolis-Hastings Robbins-Monro algorithm using the R (version 3.6.3) package mirt. Model data were fit to assess questionnaire dimensionality, to estimate item information, and to score participants. Poorly functioning items were removed, and the model was refit to create the final questionnaire. RESULTS: The psychometrically validated PROs measure was reduced to a 59-item questionnaire measuring 7 unidimesnional domains: central vision, color vision, contrast sensitivity, scotopic function, photopic peripheral vision, mesopic peripheral vision, and photosensitivity. A total of 39 items were removed because of poor factor loading, low item information, poor person-ability differentiation, or high item-level interdependence. This novel questionnaire produces a reliable domain score for person ability that does not show significant test-retest variability across repeated administration. CONCLUSIONS: The final PRO questionnaire, known as the Michigan Retinal Degeneration Questionnaire, is psychometrically validated and available for use in the evaluation of patients with inherited retinal degenerations.

Coats-like Exudative Vitreoretinopathy in Retinitis Pigmentosa: Ocular Manifestations and Treatment Outcomes.

PURPOSE: To provide a comprehensive review of the ocular manifestations, outcomes, and genetic findings in patients with Coats-like retinitis pigmentosa (RP). DESIGN: Multicenter, retrospective, nonconsecutive case series. PARTICIPANTS: Patients with a diagnosis of RP demonstrating Coats-like exudative vitreoretinopathy between January 1, 2008, and October 1, 2019. METHODS: Evaluation of ocular findings at RP diagnosis and at time of presentation of Coats-like exudative vitreoretinopathy, pedigree analysis, genetic testing, retinal imaging, and anatomic outcomes after treatment. MAIN OUTCOME MEASURES: Visual acuity, ophthalmoscopy results, OCT results, fluorescein angiography results, and identification of genetic mutations. RESULTS: Nine patients diagnosed with RP and demonstrating Coats-like exudative vitreoretinopathy were included. Median age at time of RP diagnosis was 8 years (range, 1-22 years), and median age at presentation of Coats-like exudative vitreoretinopathy was 18 years (range, 1-41 years). Seven patients were female, and 2 were male. The genetic cause of disease was identified in 6 patients. Three patients demonstrated Coats-like fundus findings at the time of RP diagnosis. Exudative retinal detachment (ERD) localized to the infratemporal periphery was present in all patients, with bilateral disease observed in 7 patients. In all treated patients, focal laser photocoagulation was used to treat leaking telangiectasias and to limit further ERD expansion. Cystoid macular edema refractory to carbonic anhydrase inhibitor therapy and ultimately amenable to treatment with intravitreal anti-vascular endothelial growth factor injection was observed in 4 patients. CONCLUSIONS: Coats-like vitreoretinopathy is present in up to 5% of all RP patients. The term Coats-like RP is used colloquially to describe this disease state, which can present at the time of RP diagnosis or, more commonly, develops late during the clinical course of patients with longstanding RP. Coats-like RP is distinct from Coats disease in that exudative pathologic features occur exclusively in the setting of a coexisting RP diagnosis, is restricted to the infratemporal retina, can affect both eyes, and does not demonstrate a male gender bias. Given the risk of added vision loss posed by exudative vitreoretinopathy in patients with RP, a heightened awareness of this condition is critical in facilitating timely intervention.

The Michigan Vision-Related Anxiety Questionnaire: A Psychosocial Outcomes Measure for Inherited Retinal Degenerations.

OBJECTIVE: We sought to construct and validate a patient-reported outcome measure for screening and monitoring vision-related anxiety in patients with inherited retinal degenerations. DESIGN: Item-response theory and graded response modeling to quantitatively validate questionnaire items generated from qualitative interviews and patient feedback. METHODS: Patients at the Kellogg Eye Center (University of Michigan, Ann Arbor, Michigan, USA) with a clinical diagnosis of an inherited retinal degeneration (n = 128) participated in an interviewer-administered questionnaire. The questionnaire consisted of 166 items, 26 of which pertained to concepts of "worry" and "anxiety." The subset of vision-related anxiety questions was analyzed by a graded response model using the Cai Metropolis-Hastings Robbins-Monro algorithm in the R software mirt package. Item reduction was performed based on item fit, item information, and item discriminability. To assess test-retest variability, 25 participants completed the questionnaire a second time 4 to 16 days later. RESULTS: The final questionnaire consisted of 14 items divided into 2 unidimensional domains: rod function anxiety and cone function anxiety. The questionnaire exhibited convergent validity with the Patient Health Questionnaire for symptoms of depression and anxiety. This vision-related anxiety questionnaire has high marginal reliability (0.81 for rod-function anxiety, 0.83 for cone-function anxiety) and exhibits minimal test-retest variability (ρ = 0.81 [0.64-0.91] for rod-function anxiety and ρ = 0.83 [0.68-0.92] for cone-function anxiety). CONCLUSIONS: The Michigan Vision-Related Anxiety Questionnaire is a psychometrically validated 14-item patient-reported outcome measure to be used as a psychosocial screening and monitoring tool for patients with inherited retinal degenerations. It can be used in therapeutic clinical trials for measuring the benefit of an investigational therapy on a patient's vision-related anxiety.

The RUSH2A Study: Best-Corrected Visual Acuity, Full-Field Electroretinography Amplitudes, and Full-Field Stimulus Thresholds at Baseline.

Purpose: The purpose of this study was to evaluate baseline best corrected visual acuity (BCVA), full-field electroretinography (ERG), full-field stimulus thresholds (FST), and their relationship with baseline demographic and clinical characteristics in the Rate of Progression in Usher syndrome type 2 (USH2A)-related Retinal Degeneration (RUSH2A) multicenter study. Methods: Participants had Usher syndrome type 2 (USH2, N = 80) or autosomal recessive nonsyndromic retinitis pigmentosa (ARRP, N = 47) associated with biallelic variants in the USH2A gene. Associations of demographic and clinical characteristics with BCVA, ERG, and FST were assessed with regression models. Results: In comparison to ARRP, USH2 had worse BCVA (median 79 vs. 82 letters; P < 0.001 adjusted for age), lower rod-mediated ERG b-wave amplitudes (median 0.0 vs. 6.6 µV; P < 0.001) and 30 Hz flicker cone-mediated ERG amplitudes (median 1.5 vs. 3.1 µV; P = 0.001), and higher (white, blue, and red) FST thresholds (means [-26, -31, -23 dB] vs. [-39, -45, -28 dB]; P < 0.001 for all stimuli). After adjusting for age, gender, and duration of vision loss, the difference in BCVA between diagnosis groups was attenuated (P = 0.09). Only diagnosis was associated with rod- and cone-mediated ERG parameters, whereas both genders (P = 0.04) and duration of visual loss (P < 0.001) also were associated with FST white stimulus. Conclusions: USH2 participants had worse BCVA, ERG, and FST than ARRP participants. FST was strongly associated with duration of disease; it remains to be determined whether it will be a sensitive measure of progression. Translational Relevance: Using standardized research protocols in RUSH2A, measures have been identified to monitor disease progression and treatment response and differentiate features of prognostic relevance between USH2 and ARRP participants with USH2A mutations.

Genetic testing for inherited retinal degenerations: Triumphs and tribulations.

Inherited retinal degenerations (IRDs) are a genotypically and phenotypically diverse group of conditions. Great strides have been made toward identifying the genetic basis for these conditions over the last 30 years-more than 270 different genes involved in syndromic and nonsyndromic forms of retinal dystrophies have now been identified. The identification of these genes and the improvement of clinical laboratory techniques have led to the identification of the genetic basis of disease in 56-76% of patients with IRDs through next generation sequencing and copy number variant analysis. Genetic testing is an essential part of clinical care for patients affected with IRDs and is required to confirm the diagnosis, understand the inheritance of the condition, and determine eligibility for gene-specific treatments or clinical trials. Despite the success achieved in determining the genetic cause of these conditions, several challenges remain, which must be considered when providing genetic testing and genetic counseling to patients. For this reason, an integrated team of ophthalmic and genetic clinicians who are familiar with these challenges is necessary to provide optimal comprehensive care to these patients.

Advancing Clinical Trials for Inherited Retinal Diseases: Recommendations from the Second Monaciano Symposium.

Major advances in the study of inherited retinal diseases (IRDs) have placed efforts to develop treatments for these blinding conditions at the forefront of the emerging field of precision medicine. As a result, the growth of clinical trials for IRDs has increased rapidly over the past decade and is expected to further accelerate as more therapeutic possibilities emerge and qualified participants are identified. Although guided by established principles, these specialized trials, requiring analysis of novel outcome measures and endpoints in small patient populations, present multiple challenges relative to study design and ethical considerations. This position paper reviews recent accomplishments and existing challenges in clinical trials for IRDs and presents a set of recommendations aimed at rapidly advancing future progress. The goal is to stimulate discussions among researchers, funding agencies, industry, and policy makers that will further the design, conduct, and analysis of clinical trials needed to accelerate the approval of effective treatments for IRDs, while promoting advocacy and ensuring patient safety.

Rapid visual field constriction in a patient with retinitis pigmentosa and pituitary adenoma.

PURPOSE: To report a case of pituitary adenoma in a patient with retinitis pigmentosa (RP) and consequent rapid constriction of the visual field in each eye, which is atypical for either of these pathologies. OBSERVATIONS: A 45-year old male, with a long-standing history of RP, presented with rapid vision loss over 3 months. Examination revealed a severe drop in visual acuity and significant progression of concentric visual field constriction in each eye compared to 3 months prior. MRI revealed a pituitary macroadenoma compressing the optic chiasm. The patient underwent endoscopic trans-sphenoidal resection of the tumor and experienced partial recovery of visual acuity but not visual field. CONCLUSIONS AND IMPORTANCE: The visual field deficit in this patient was atypical for pituitary adenoma or optic neuropathy. The pattern was most consistent with RP, but the rate of progression was not. In a patient with chiasmal pathology in the setting of pre-existing retinopathy, visual field progression may not be limited exclusively to the bitemporal regions. Rapid constriction of the visual field in a patient with RP should prompt a work-up for alternative etiologies which includes neuro-imaging.

Autoimmune retinopathy associated with monoclonal gammopathy of undetermined significance: a case report.

BACKGROUND: Monoclonal gammopathy of undetermined significance (MGUS) is a plasma cell dyscrasia and precursor to multiple myeloma. It has known ocular manifestations, but has not previously been shown to have an association with autoimmune retinopathy. CASE PRESENTATION: A 57 year-old female presented with 1 year of progressive, bilateral, peripheral vision loss, photopsias, and nyctalopia. Her fundus examination and extensive ancillary testing were concerning for hereditary versus autoimmune retinopathy. The patient was found to have anti-retinal antibodies against carbonic anhydrase II and enolase proteins with a negative genetic retinal dystrophy panel. Malignancy work-up was negative, but the patient was diagnosed with MGUS, a premalignant condition. The patient was treated with immunosuppressive therapies, with rituximab demonstrating the most robust therapeutic response with respect to patient symptoms and ophthalmic testing. CONCLUSIONS: MGUS should be considered as a potential etiology of autoimmune retinopathy in patients without other autoimmune or malignant disease processes. Immunosuppressive therapy may be helpful in limiting disease progression, with rituximab showing efficacy in retinopathy refractory to other agents.

X-Chromosome Inactivation Is a Biomarker of Clinical Severity in Female Carriers of RPGR-Associated X-Linked Retinitis Pigmentosa.

PURPOSE: X-linked retinitis pigmentosa can manifest in female carriers with widely variable severity, whereas others remain unaffected. The contribution of X-chromosome inactivation (XCI) to phenotypic variation has been postulated but not demonstrated. Furthermore, the impact of genotype and genetic modifiers has been demonstrated in affected males but has not been well established in female carriers. The purpose of this study was to describe the scope of clinical phenotype in female carriers with mutations in RPGR and quantify the contribution of genotype, genetic modifiers, and XCI to phenotypic severity. DESIGN: Cohort study. PARTICIPANTS: Seventy-seven female carriers with RPGR mutations from 41 pedigrees. METHODS: Coding single nucleotide polymorphisms were sequenced in candidate genetic modifier genes encoding known RPGR-interacting proteins. X-chromosome inactivation ratios were determined in genomic DNA isolated from blood (n = 42) and saliva (n = 20) using methylation status of X-linked polymorphic repeats. These genetic data were compared with disease severity based on quantitative clinical parameters. MAIN OUTCOME MEASURES: Visual acuity, Humphrey visual field (HVF) results, full-field electroretinography results, and dark adaptation. RESULTS: Most individuals at all ages were mildly affected or unaffected, whereas those who progressed to moderate or severe vision loss were older than 30 years. RPGR genotype was not associated with clinical severity. The D1264N variant in RPGRIP1L was associated with more severe disease. Skewed XCI toward inactivation of the normal RPGR allele was associated with more severe disease. The XCI ratio in both blood and saliva was a predictor of visual function as measured by HVF diameter, rod amplitude, flicker amplitude, and flicker implicit time. For carriers with extreme XCI skewing of 80:20 or more, 57% were affected severely compared with 8% for those with XCI of less than 80:20 (P = 0.002). CONCLUSIONS: Female carriers with mutations in RPGR demonstrate widely variable clinical severity. X-chromosome inactivation ratios correlate with clinical severity and may serve as a predictor of clinically significant disease. Because RPGR gene therapy trials are underway, a future imperative exists to determine which carriers require intervention and when to intervene. X-chromosome inactivation analysis may be useful for identifying candidates for early intervention.