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Age-related macular degeneration (AMD) is a multifactorial retinal disease with a large genetic risk contribution. Reticular pseudodrusen (RPD) is a sub-phenotype of AMD with a high risk of progression to late vision threatening AMD. In a genome-wide association study of 2,165 AMD+/RPD+ and 4,181 AMD+/RPD-compared to 7,660 control participants, both chromosomes 1 ( CFH ) and 10 ( ARMS2/HTRA1 ) major AMD risk loci were reidentified. However association was only detected for the chromosome 10 locus when comparing AMD+/RPD+ to AMD+/RPD-cases. The chromosome 1 locus was notably absent. The chromosome 10 RPD risk region contains a long non-coding RNA (ENSG00000285955/BX842242.1) which colocalizes with genetic markers of retinal thickness. BX842242.1 has a strong retinal eQTL signal, pinpointing the parafoveal photoreceptor outer segment layer. Whole genome sequencing of phenotypically extreme RPD cases identified even stronger enrichment for the chromosome 10 risk genotype.

Geographic atrophy (GA), the non-neovascular advanced form of age-related macular degeneration, remains an important disease area in which treatment needs are currently unmet. Recent clinical trials using drugs that target the complement pathway have shown modest yet consistent reductions in GA expansion but without commensurate changes in measures of visual function. In this review, we summarize information from the wide range of studies describing the characteristics of GA morphology and enumerate the factors influencing the growth rates of lesions and the directionality of expansion. In addition, we review the relationship between GA growth and the various measures of vision that reflect changes in function. We consider the reasons for the discordance between the anatomical and functional endpoints in current use and discuss methods to align these key outcomes.

Purpose: To explore the contributions of fundus autofluorescence (FAF) topographic imaging features to the performance of convolutional neural network-based deep learning (DL) algorithms in predicting geographic atrophy (GA) growth rate., Methods: Retrospective study with data from study eyes from three clinical trials (NCT02247479, NCT02247531, NCT02479386) in GA. The algorithm was initially trained with full FAF images, and its performance was considered benchmark. Ablation experiments investigated the contribution of imaging features to the performance of the algorithms. Three FAF image regions were defined relative to GA: Lesion, Rim, and Background. For No Lesion, No Rim, and No Background datasets, a single region of interest was removed at a time. For Lesion, Rim, and Background Shuffled datasets, individual region pixels were randomly shuffled. For Lesion, Rim, and Background Mask datasets, masks of the regions were used. A Convex Hull dataset was generated to evaluate the importance of lesion size. Squared Pearson correlation (r2) was used to compare the predictive performance of ablated datasets relative to the benchmark., Results: The Rim region influenced r2 more than the other two regions in all experiments, indicating the most relevant contribution of this region to the performance of the algorithms. In addition, similar performance was observed for all regions when pixels were shuffled or only a mask was used, indicating intensity information was not independently informative without textural context., Conclusions: These ablation experiments enabled topographic clinical insights on FAF images from a DL-based GA progression prediction algorithm., Translational Relevance: Results from this study may lead to new insights on GA progression prediction.

Degenerative diseases of the outer retina, including age-related macular degeneration (AMD), are characterized by atrophy of photoreceptors and retinal pigment epithelium (RPE). In these blinding diseases, macrophages are known to accumulate ectopically at sites of atrophy, but their ontogeny and functional specialization within this atrophic niche remain poorly understood, especially in the human context. Here, we uncovered a transcriptionally unique profile of microglia, marked by galectin-3 upregulation, at atrophic sites in mouse models of retinal degeneration and in human AMD. Using disease models, we found that conditional deletion of galectin-3 in microglia led to defects in phagocytosis and consequent augmented photoreceptor death, RPE damage and vision loss, suggestive of a protective role. Mechanistically, Trem2 signaling orchestrated the migration of microglial cells to sites of atrophy, and there, induced galectin-3 expression. Moreover, pharmacologic Trem2 agonization led to heightened protection, but only in a galectin-3-dependent manner, further signifying the functional interdependence of these two molecules. Likewise in elderly human subjects, we identified a highly conserved population of microglia at the transcriptomic, protein and spatial levels, and this population was enriched in the macular region of postmortem AMD subjects. Collectively, our findings reveal an atrophy-associated specialization of microglia that restricts the progression of retinal degeneration in mice and further suggest that these protective microglia are conserved in AMD.

Purpose: To correlate ellipsoid zone (EZ) defects on spectral-domain optical coherence tomography (SD-OCT) with retinal sensitivity loss on macular integrity assessment (MAIA) microperimetry in macular telangiectasia type 2 (MacTel)., Methods: Macular SD-OCT volumes and microperimetry maps were obtained during the international, multicenter, randomized phase 2 trial of ciliary neurotrophic factor for type 2 MacTel on two visits within 5 days of one another. Software was developed to register SD-OCT to MAIA scanning laser ophthalmoscopy images and to overlay EZ defect areas on the microperimetry maps generated from microperimetry sensitivity values at specific points and from interpolated sensitivity values. A total of 134 eyes of 67 patients were investigated., Results: The semiautomated registration algorithm was found to be accurate, both qualitatively by visual inspection of the nearly perfect overlap of the retinal vessels and quantitatively as assessed by interobserver reliability metrics performed in 98 eyes of 49 patients (intraclass correlation of aggregate retinal sensitivity loss >0.99). Aggregate retinal sensitivity loss within the EZ defect area was highly correlated with EZ defect area (Pearson correlation coefficient 0.93 and 0.92 at screening and baseline for noninterpolated maps; both were 0.94 for interpolated maps; P values <0.001)., Conclusions: With our software and image processing algorithms, there is nearly perfect correlation between retinal sensitivity on microperimetry and EZ defect area on SD-OCT. Our software allows determination of functional and structural changes with increasing disease severity and demonstrates that functional loss on microperimetry may be used as a surrogate marker of EZ loss on SD-OCT in type 2 MacTel.

Purpose: The present study aimed to examine cost, demographics, and short-term complications associated with orbital fractures and their surgical repair in the inpatient population in the United States over a 7-year period., Methods: A retrospective cohort study was performed by using the Nationwide Inpatient Sample from 2002 to 2008 and searching the database for discharges classified with International Classification of Disease-9 diagnosis codes of orbital fractures, orbital fracture repair, and associated diagnoses., Results: There was nearly a 50% increase in the annual number of orbital fracture admissions from 2002 to 2008. Demographics for patients with orbital fractures showed that 68% of them were male, most commonly between 18 and 44 years of age, with 69% of cases at large teaching hospitals. Associated ocular diagnoses included eyelid laceration, commotio retinae, and globe rupture. Approximately 25% of patients underwent surgical repair. Surgical patients were younger than nonsurgical patients by approximately 10 years. An overall complication rate of 15.8% was noted, including: pulmonary complications, diplopia, renal impairment, venous thromboembolism, and wound complications. Orbital fracture repair was associated with approximately 1 extra day of hospitalization and $22,000 in-hospital charges. The rates of pulmonary, wound, and ocular motility complications were significantly higher in the patients undergoing orbital fracture repair (p<0.05)., Conclusions: The number of orbital fractures and associated cost has dramatically increased over the past decade. Acute repair of orbital fractures is common and is associated with a longer hospital course, increased cost, and higher rate of complications.