Faculty Bibliography

Purpose/UNASSIGNED:To develop a machine-learning image processing model for three-dimensional (3D) reconstruction of vitreous anatomy visualized with swept-source optical coherence tomography (SS-OCT). Methods/UNASSIGNED:Healthy subjects were imaged with SS-OCT. Scans of sufficient quality were transferred into the Fiji is just ImageJ image processing toolkit, and proportions of the resulting stacks were adjusted to form cubic voxels. Image-averaging and Trainable Weka Segmentation using Sobel and variance edge detection and directional membrane projections filters were used to enhance and interpret the signals from vitreous gel, liquid spaces within the vitreous, and interfaces between the former. Two classes were defined: "Septa" and "Other." Pixels were selected and added to each class to train the classifier. Results were generated as a probability map. Thresholding was performed to remove pixels that were classified with low confidence. Volume rendering was performed with TomViz. Results/UNASSIGNED:Forty-seven eyes of 34 healthy subjects were imaged with SS-OCT. Thirty-four cube scans from 25 subjects were of sufficient quality for volume rendering. Clinically relevant vitreous features including the premacular bursa, area of Martegiani, and prevascular vitreous fissures and cisterns, as well as varying degrees of vitreous degeneration were visualized in 3D. Conclusions/UNASSIGNED:A machine-learning model for 3D vitreous reconstruction of SS-OCT cube scans was developed. The resultant high-resolution 3D movies illustrated vitreous anatomy in a manner like triamcinolone-assisted vitrectomy or postmortem dye injection. Translational Relevance/UNASSIGNED:This machine learning model now allows for comprehensive examination of the vitreous structure beyond the vitreoretinal interface in 3D with potential applications for common disease states such as the vitreomacular traction and Macular Hole spectrum of diseases or proliferative diabetic retinopathy.

PURPOSE/OBJECTIVE:Soft drusen and subretinal drusenoid deposits (SDDs) characterize two pathways to advanced age-related macular degeneration (AMD), with distinct genetic risks, serum risks and associated systemic diseases. METHODS:126 Subjects with AMD were classified as SDD (with or without soft drusen), or non-SDD (drusen only) by retinal imaging, with serum risks, genetic testing, and histories of cardiovascular disease (CVD) and stroke. RESULTS:There were 62 SDD subjects and 64 non-SDD subjects, 51 total had CVD or stroke.SDD correlated significantly with: lower mean serum HDL (61±18 vs. 69±22 mg/dl, p= 0.038, t test); CVD and stroke (34/51 SDD, p= 0.001, chi square); ARMS2 risk allele (p= 0.019, chi square), but not with CFH risk allele (p = 0.66). Non-SDD (drusen only) correlated/trended with: APOE2 (p= 0.032) and CETP (p= 0.072) risk alleles (chi square). Multivariate independent risks for SDD were: CVD and stroke (p= 0.008), and ARMS2 homozygous risk (p= 0.038). CONCLUSION/CONCLUSIONS:SDD and non-SDD subjects have distinct systemic associations, serum and genetic risks. SDD are associated with CVD and stroke, ARMS2 risk, and lower HDL; non-SDD with higher HDL, CFH risk and two lipid risk genes. These and other distinct associations suggest these lesions are markers for distinct diseases.

PURPOSE/OBJECTIVE:To report a case of branch retinal artery occlusion associated with paracentral acute middle maculopathy on spectral-domain optical coherence tomography presumably related to heavy cannabis consumption. METHODS:Retrospective case report. Spectral-domain optical coherence tomography, fluorescein angiography, and optical coherence tomography angiography were performed. RESULTS:A 21-year-old healthy man described the acute onset of superior visual field loss in his right eye. He admitted smoking approximately 15 g daily of cannabis for several weeks during COVID-19 confinement. Ophthalmoscopic examination of the right eye showed inferotemporal retinal whitening. Spectral-domain optical coherence tomography illustrated evidence of the ischemic cascade with diffuse hyperreflectivity of the inner and middle retinal layers within the central region of the retinal infarct and paracentral acute middle maculopathy at the border of the infarct. Optical coherence tomography angiography demonstrated predominant flow signal loss at the level of the deep retinal capillary plexus. Fluorescein angiography and complete systemic workup were unremarkable. CONCLUSION/CONCLUSIONS:Branch retinal artery occlusion and paracentral acute middle maculopathy may be related to heavy cannabis use as the result of transient arterial vasospasm.

Importance/UNASSIGNED:By validating optical coherence tomography angiography (OCTA) in the analysis of type 3 macular neovascularization secondary to age-related macular degeneration, the overall value of clinical OCTA for disease observation, diagnosis, and staging is increased. Objective/UNASSIGNED:To assess the association of in vivo OCTA of type 3 macular neovascularization secondary to age-related macular degeneration with corresponding ex vivo histology. Design, Setting, and Participants/UNASSIGNED:This study included clinical imaging, laboratory microscopy, and eye-tracked clinicopathologic correlation of a single case from a community-based practice evaluated at a university-based research laboratory from 2014 to 2019. Exposures/UNASSIGNED:Infrared reflectance and eye-tracked spectral-domain OCTA clinical imaging was correlated with ex vivo high-resolution histologic images of the preserved donor eye. Eye tracking, applied to the donor eye, enabled identification of histologic features corresponding with clinical OCTA signatures. Projection artifact removal based on 2-dimensional vessel-shape estimation and a Gaussian blur filter demonstrated a robust preservation of neovascular flow signal. Main Outcomes and Measures/UNASSIGNED:Histology findings associated with clinical OCTA signatures. Three-dimensional view of neovascularization via video. Results/UNASSIGNED:A White woman in her 90s with type 3 neovascularization secondary to age-related macular degeneration was treated with 37 intravitreal injections of ranibizumab and aflibercept in the right eye. The index lesion displayed a drusenoid pigment epithelium detachment, characteristic of type 3 neovascularization. OCTA decorrelation signal in the index lesion corresponded in histology to a collagen-ensheathed vascular complex contacting basal laminar deposit that outlasted the retinal pigment epithelium. The subretinal pigment epithelium-basal laminar space contained calcified material and glial processes. No connection between the choriocapillaris and this space was observed. Video showed a columnar tangle of flow signal in the outer nuclear layer, with inflow and outflow vessels connecting to the superficial artery and vein. Conclusions and Relevance/UNASSIGNED:While this study presents only 1 case in which a vascular connection between subretinal pigment epithelium-basal laminar space and choriocapillaris was undetected, these results support the potential value of OCTA for diagnosis. OCTA decorrelation signal of type 3 neovascularization corresponded with intraretinal neovessels on histology. Projection artifact removal based on 2-dimensional vessel-shape estimation and Gaussian blur filter demonstrated their potential value for further use in OCTA decorrelation signal processing.

Purpose:To characterize macular blood flow connectivity in vivo using high-resolution optical coherence tomography (HighRes OCT). Methods:Cross-sectional, observational study. Dense (6-µm interscan distance) perifoveal HighRes OCT raster scans were performed on healthy participants. To mitigate the limitations of projection-resolved OCT-angiography, flow and structural data were used to observe the vascular structures of the superficial vascular complex (SVC) and the deep vascular complex. Vascular segmentation and rendering were performed using Imaris 9.5 software. Inflow and outflow patterns were classified according to vascular diameter and branching order from superficial arteries and veins, respectively. Results:Eight eyes from eight participants were included in this analysis, from which 422 inflow and 459 outflow connections were characterized. Arteries had direct arteriolar connections to the SVC (78%) and to the intermediate capillary plexus (ICP, 22%). Deep capillary plexus (DCP) inflow derived from small-diameter vessels succeeding ICP arterioles. The most prevalent outflow pathways coursed through superficial draining venules (74%). DCP draining venules ordinarily merged with ICP draining venules and drained independently of superficial venules in 21% of cases. The morphology of DCP draining venules in structural HighRes OCT is distinct from other vessels crossing the inner nuclear layer and can be used to identify superficial veins. Conclusions:Vascular connectivity analysis supports a hybrid circuitry of blood flow within the human parafoveal macula. Translational Relevance:Characterization of parafoveal macular blood flow connectivity in vivo using a precise segmentation of HighRes OCT is consistent with ground-truth microscopy studies and shows a hybrid circuitry.

PURPOSE/OBJECTIVE:To describe the recovery timeline of spots and dots in multiple evanescent white dot syndrome. METHODS:Sequential multimodal retinal imaging including fundus autofluorescence and cross-sectional and en face optical coherence tomography was performed to track the development and resolution of spots and dots in a case of multiple evanescent white dot syndrome. RESULTS:En face optical coherence tomography showed that the spots are the result of ellipsoid zone loss and are hyperautofluorescent due to unmasking of the underlying retinal pigment epithelium autofluorescence. Conversely, the dots are hyperreflective with cross-sectional and en face optical coherence tomography and hyperautofluorescent, which we propose may be due to accumulation of degenerated photoreceptor material including fluorophores with autofluorescent capability such as precursors of A2E. The earlier resolution of the hyperautofluorescent spots allowed for later detection of the hyperautofluorescent dots. CONCLUSION/CONCLUSIONS:This case report illustrates the different recovery timelines of spots and dots in multiple evanescent white dot syndrome. Although both lesion types are hyperautofluorescent, the mechanism of autofluorescence is distinctive and may be explained by their contrasting pathoanatomy.

INTRODUCTION/UNASSIGNED:White dot syndromes are a heterogeneous group of diseases that affect different layers in the retina and choroid. Multimodal imaging is fundamental in the diagnosis, but also can be crucial in unveiling the pathogenesis of these entities. MATERIAL AND METHODS/UNASSIGNED:Literature review. RESULTS/UNASSIGNED:Optical coherence tomography (OCT) provides depth-resolved, histological grade images of the vitreous, retina, and choroid. This technology is very useful to localize the primary nature and level of pathology of the various white dot syndromes. En face OCT can provide additional information regarding the interrelationship of lesion types. Vascular involvement at the level of the retina, choriocapillaris or choroid can be assessed by en face OCT angiography (OCT-A) and is not limited by masking, leakage or staining as can occur with conventional angiography (fluorescein or indocyanine green angiography) which requires dye injection. CONCLUSION/UNASSIGNED:OCT and OCTA are fundamental in the diagnosis and follow-up of white dots syndromes.

PURPOSE/OBJECTIVE:To determine the prevalence and characteristics of multifocal choroiditis/punctate inner choroidopathy (MFC/PIC) in eyes with patchy atrophy due to pathologic myopia (PM). METHOD/METHODS:Five hundred eyes of 253 patients with patchy atrophy were examined between 2014 and 2020 at the Advanced Clinical Center for Myopia. The main outcome measures included the prevalence and characteristics of active MFC/PIC lesions diagnosed by optical coherence tomography (OCT). RESULTS:Fifty-five of the 500 eyes (11%) diagnosed with patchy atrophy had OCT features of active MFC/PIC lesions such as focal elevations of the RPE filled with medium hyperreflectivity material, curvilinear scars (Schlaegel lines), and/or areas of outer retinal atrophy. At the time when the MFC/PIC was diagnosed, the mean age was 57.3±12.0 years, and the mean axial length was 29.2±1.8 mm. Macular neovascularization (MNV) was found in 45 of eyes (81.8%) with MFC/PIC vs 151 eyes without such findings (33.9%; P <0.001). In 25 of the 55 eyes (45.5%), active MFC/PIC lesions were found before the development of the patchy atrophy. The Bruch's membrane defects were co-located with these lesions. CONCLUSIONS:Active MFC/PIC lesions were identified in a minority of eyes with PM, and a subset of these lesions were observed to progress to findings indistinguishable from myopic patchy atrophy. Evidence of MFC/PIC in eyes with PM appeared to be a risk factor for the development of MNV.