RAVIR: A Dataset and Methodology for the Semantic Segmentation and Quantitative Analysis of Retinal Arteries and Veins in Infrared Reflectance Imaging.

The retinal vasculature provides important clues in the diagnosis and monitoring of systemic diseases including hypertension and diabetes. The microvascular system is of primary involvement in such conditions, and the retina is the only anatomical site where the microvasculature can be directly observed. The objective assessment of retinal vessels has long been considered a surrogate biomarker for systemic vascular diseases, and with recent advancements in retinal imaging and computer vision technologies, this topic has become the subject of renewed attention. In this paper, we present a novel dataset, dubbed RAVIR, for the semantic segmentation of Retinal Arteries and Veins in Infrared Reflectance (IR) imaging. It enables the creation of deep learning-based models that distinguish extracted vessel type without extensive post-processing. We propose a novel deep learning-based methodology, denoted as SegRAVIR, for the semantic segmentation of retinal arteries and veins and the quantitative measurement of the widths of segmented vessels. Our extensive experiments validate the effectiveness of SegRAVIR and demonstrate its superior performance in comparison to state-of-the-art models. Additionally, we propose a knowledge distillation framework for the domain adaptation of RAVIR pretrained networks on color images. We demonstrate that our pretraining procedure yields new state-of-the-art benchmarks on the DRIVE, STARE, and CHASE_DB1 datasets. Dataset link: https://ravirdataset.github.io/data.

MULTIMODAL IMAGING OF RECURRENT CYSTOID MACULAR EDEMA ASSOCIATED WITH POEMS SYNDROME RESPONSIVE TO INTRAVITREAL DEXAMETHASONE IMPLANT.

PURPOSE: To describe the multimodal imaging findings of cystoid macular edema (CME) in POEMS syndrome and to demonstrate the effectiveness of the dexamethasone intravitreal implant in this condition. METHODS: A case report of a patient with POEMS syndrome. Multimodal imaging, including optical coherence tomography and ultra-wide field fluorescein angiography, was used to evaluate the CME and its response to treatment. RESULTS: A 66-year-old man with a history of POEMS syndrome in clinical remission after chemotherapy presented with blurry vision in the left eye. Vitreomacular traction and CME were noted on optical coherence tomography. After pars plana vitrectomy, the patient had persistent CME in the left eye and developed new CME in the right eye, which worsened over the next year. Visual acuities at this time were 20 of 60 in both eyes. The CME was unresponsive to topical ketorolac and prednisolone acetate and intravitreal bevacizumab but partially response to intravitreal and sub-Tenon's triamcinolone acetate injections. Intravitreal dexamethasone implant was given bilaterally with full resolution and visual acuities improvement to 20 of 40 in the right eye and 20 of 30 in the left eye. However, CME recurred after 3 months. Ultra-wide field fluorescein angiography demonstrated bilateral CME and diffuse peripheral vascular leakage. Serum vascular endothelial growth factor levels were normal. CONCLUSION: Cystoid macular edema may develop in POEMS syndrome in the absence of systemic findings, elevated serum vascular endothelial growth factor, or optic nerve edema. Previously unreported peripheral vascular leakage was demonstrated on ultra-wide field fluorescein angiography. Dexamethasone implant was the most effective of used therapies to treat CME.

Epiretinal proliferation after rhegmatogenous retinal detachment.

PURPOSE: To determine the characteristics and appearance rate of epiretinal proliferation (ERP) on SD-OCT after surgery for rhegmatogenous retinal detachment (RRD) repair. METHODS: One hundred eight eyes of 108 patients who underwent one or more surgeries for RRD were enrolled. The eyes with other maculopathies that were directly related to RRD were excluded. Image acquisition was performed with SD-OCT (Heidelberg Engineering, Germany). Clinical charts were reviewed to assess clinical and surgical findings. Statistical analyses were performed using XLSTAT (Assinsoft, Paris, France). RESULTS: ERP was found in 9.3% eyes (n = 10). The mean initial visual acuity (logMAR) was 1.34 ± 0.82 in the ERP group compared to 0.49 ± 0.70 in the non-ERP group. PVR was present in 70.0% and chronic macular edema was found in 80.0% of eyes which developed ERP. The mean number of vitreoretinal surgeries in eyes with ERP was 3.3 ± 1.19 and only 1.44 ± 1.02 in eyes without. Silicone oil was used in 60.0% of eyes which developed ERP compared to 13.9% in the non-ERP group. CONCLUSION: ERP is a late-onset postoperative finding in eyes with RRD and can occur in absence of macular holes. Overall, ERP is more frequent in eyes with complicated courses of RRD including multiple operations, PVR, usage of silicone oil, and chronic macular edema.

Fundus Autofluorescence and Clinical Applications.

Fundus autofluorescence (FAF) has allowed in vivo mapping of retinal metabolic derangements and structural changes not possible with conventional color imaging. Incident light is absorbed by molecules in the fundus, which are excited and in turn emit photons of specific wavelengths that are captured and processed by a sensor to create a metabolic map of the fundus. Studies on the growing number of FAF platforms has shown each may be suited to certain clinical scenarios. Scanning laser ophthalmoscopes, fundus cameras, and modifications of these each have benefits and drawbacks that must be considered before and after imaging to properly interpret the images. Emerging clinical evidence has demonstrated the usefulness of FAF in diagnosis and management of an increasing number of chorioretinal conditions, such as age-related macular degeneration, central serous chorioretinopathy, retinal drug toxicities, and inherited retinal degenerations such as retinitis pigmentosa and Stargardt disease. This article reviews commercial imaging platforms, imaging techniques, and clinical applications of FAF.

En Face Optical Coherence Tomography Imaging of Foveal Dots in Eyes With Posterior Vitreous Detachment or Internal Limiting Membrane Peeling.

Purpose: To analyze the morphology of foveal hyperreflective dots (HRD) identified with en face optical coherence tomography (OCT) and evaluate the effects of internal limiting membrane (ILM) peeling and posterior vitreous detachment (PVD) on the number of these lesions. Methods: Retrospective cross-sectional study of patients with OCT angiography and en face OCT. Using en face OCT, superficial HRD lying on the foveal floor were measured and quantitated in eyes with ILM peel and in the fellow nonsurgical eyes. Eyes with foveal PVD were also compared to fellow eyes without foveal PVD. High-magnification en face OCT was also performed to better understand the morphology of HRD in the fovea. Results: Eyes that underwent ILM peel (n = 10) displayed fewer HRD (P = 0.012) compared to control fellow nonoperated eyes. In eyes with foveal PVD, the mean number of HRD was numerically greater, but without statistical significance, compared to the contralateral eye without foveal PVD. High-magnification en face OCT illustrated HRD with irregular shapes and fine cilia-like or dendriform extensions. Average length of HRD was between 15 to 21 µm in all four groups. Conclusions: HRD decreased in eyes with ILM peeling by en face OCT compared with fellow nonoperated eyes and exhibited a glial cell-like morphology and size closely resembling the white dot fovea described previously using scanning electron microscopy. HRD may represent processes of activated retinal glia, possibly Muller cells, that traverse defects in the ILM.

Macular edema after rhegmatogenous retinal detachment repair: risk factors, OCT analysis, and treatment responses.

PURPOSE: To investigate risk factors, imaging characteristics, and treatment responses of cystoid macular edema (CME) after rhegmatogenous retinal detachment (RRD) repair. METHODS: Consecutive, retrospective case-control series of patients who underwent pars plana vitrectomy (PPV) and/or scleral buckling (SB) for RRD, with at least six months of follow-up. Clinical and surgical parameters of patients with and without CME (nCME), based on spectral-domain optical coherence tomography (OCT), were compared. RESULTS: Of 99 eyes enrolled, 25 had CME while 74 had nCME. Patients with CME underwent greater numbers of surgeries (P < 0.0001). After adjusting for number of surgeries, macula-off RRD (P = 0.06), proliferative vitreoretinopathy (PVR) (P = 0.09), surgical approach (PPV and/or SB, P = 0.21), and tamponade type (P = 0.10) were not statistically significant, although they all achieved significance on univariate analysis (P = 0.001 or less). Intraoperative retinectomy (P = 0.009) and postoperative pseudophakia or aphakia (P = 0.008) were more frequent in the CME group, even after adjustment. Characteristics of cCME on OCT included diffuse distribution, confluent cysts, and absence of subretinal fluid or intraretinal hyperreflective foci. Macular thickness improved significantly with intravitreal triamcinolone (P = 0.016), but not with anti-vascular endothelial growth factor agents (P = 0.828) or dexamethasone implant (P = 0.125). After adjusting for number of surgeries and macular detachment, final visual acuities remained significantly lower in the CME vs nCME group (P = 0.012). CONCLUSION: Risk factors of CME include complex retinal detachment repairs requiring multiple surgeries, and pseudophakic or aphakic lens status. Although this cCME was associated with poor therapeutic response, corticosteroids were the most effective studied treatments.

Utility of optical coherence tomography angiography in pregnancy-associated central serous chorioretinopathy.

PURPOSE: To describe a case of pregnancy-related central serous chorioretinopathy (pCSCR) and the utility of monitoring with optical coherence tomography (OCT) and OCT angiography (OCTA). OBSERVATIONS: A 34-year-old female in her third trimester of pregnancy presented with symptomatic visual disturbances of the right eye. Medical history was otherwise unremarkable. Optical coherence tomography (OCT) disclosed a serous retinal detachment with trace subretinal fibrin and elevation of the retinal pigment epithelium (RPE). OCT angiography (OCTA) demonstrated absence of choroidal neovascular membrane (CNV). It was decided to monitor with weekly OCTs until delivery, after which the patient had full resolution of symptoms and subretinal fluid. CONCLUSIONS AND IMPORTANCE: Pregnancy-related CSCR may be complicated by fibrin deposition and RPE changes suspicious for CNV. This provides evidence of the utility of OCT for monitoring pCSCR progression and of OCTA to non-invasively assess presence of CNV.

The Role of Deimination in Regenerative Reprogramming of Neurons.

Neurons from the adult central nervous system (CNS) demonstrate limited mRNA transport and localized protein synthesis versus developing neurons, correlating with lower regenerative capacity. We found that deimination (posttranslational conversion of protein-bound arginine into citrulline) undergoes upregulation during early neuronal development while declining to a low basal level in adults. This modification is associated with neuronal arborization from amphibians to mammals. The mRNA-binding proteins (ANP32a, REF), deiminated in neurons, have been implicated in local protein synthesis. Overexpression of the deiminating cytosolic enzyme peptidyl arginine deiminase 2 in nervous systems results in increased neuronal transport and neurite outgrowth. We further demonstrate that enriching deiminated proteins rescues transport deficiencies both in primary neurons and mouse optic nerve even in the presence of pharmacological transport blockers. We conclude that deimination promotes neuronal outgrowth via enhanced transport and local protein synthesis and represents a new avenue for neuronal regeneration in the adult CNS.

Surgical versus medical treatment for ocular surface squamous neoplasia: A quality of life comparison.

PURPOSE: To characterize vision-related and psychosocial quality of life (QoL) parameters in medically and surgically treated patients with OSSN. METHODS: Forty-one patients with OSSN treated with medical therapy consisting of interferon alpha 2b drops 1 MIU/ml (n = 22) or who underwent surgical excision (n = 19) were contacted. All subjects answered a quality of life assessment with an original questionnaire in which they were asked about a range of parameters. Overall satisfaction and motivating factors for treatment were also reviewed. RESULTS: The mean age at the time of the survey was 64.6 and 51% were male with similar demographics between groups. Based on the previous cohort, rates of tumor resolution and recurrences were comparable in the two groups. Reasons for choosing a particular treatment varied between the groups. Forty percent of individuals in the medical group reported a fear of surgery (p = 0.03) and often made the decision after personal research (p = 0.008). Thirty-two percent of patients in the surgical group chose surgery due to fear of decreased vision due to lesion growth, therefore wanting immediate resolution (p = 0.09). Drops precipitated more ocular symptoms such as tearing and itchiness, on the other hand, patients who had surgery reported having more pain. CONCLUSION: Quality of life considerations before, during, and after OSSN treatment is an important yet understudied topic. Our study is the first to look at QoL parameters in OSSN treatment and we found that patients in both medically and surgically treated groups had similar QoL metric but were driven to choose chemotherapy due to fear of surgery and/or prior literature review.

Evaluating Self-Refraction and Ready-Made Spectacles for Treatment of Uncorrected Refractive Error.

PURPOSE: Uncorrected refractive error is the leading cause of visual impairment worldwide and has significant quality of life and economic implications. Treatment with subjective refraction and custom-made spectacles requires expensive equipment and highly trained personnel. We examine several alternatives. METHODS: Patients were taught to self-refract using two devices: AdSpecs and the I-test Vision Screener. Ready-made spectacles were fit to the self-refraction and visual acuity (VA) was measured. Donated-spectacles were fit to subjective refraction and VA was measured. Self-refraction and donated spectacles spherical equivalent (SE) and VA were compared to subjective refraction SE and VA. RESULTS: About 57 patients (102 eyes) were enrolled in the study. Patients accurately determined refractive power with self-refraction by both AdSpecs and the I-test (compared to subjective refraction SE, r2 = 0.97 and r2 = 0.94, respectively). SE of donated spectacles fit well with self-refraction SE (r2 = 0.91). There was no significant difference between best-corrected VA by subjective refraction and VA treated by ready-made spectacles fit to self-refraction by either device (analysis of variance (ANOVA), p non-significant). Patients fit with donated spectacles had significantly worse VA than best-corrected VA by subjective refraction (ANOVA, p < 0.01), although 80% improved to >20/40. CONCLUSION: Patients accurately self-refract using both devices and ready-made spectacles fit to self-refraction have excellent visual outcomes. Donated spectacles have worse visual outcomes but might be useful in a subset of patients. Ready-made spectacles fit to self-refraction may provide a treatment alternative to uncorrected refractive error.

High-Resolution Optical Coherence Tomography Findings of Lisch Epithelial Corneal Dystrophy.

PURPOSE: To describe a case of Lisch epithelial corneal dystrophy (LECD) and present its unique characteristics on high-resolution optical coherence tomography (HR-OCT). METHODS: A 78-year-old man with whorled corneal epithelial opacities in the right eye was referred for the evaluation of ocular surface squamous neoplasia. Clinical evaluation, photographs, and HR-OCT images of the cornea involved were obtained and scrapings of the affected cornea were sent for histopathologic analysis. RESULTS: Clinically, the patient presented with an opalescent whirling epithelium in a linear pattern encroaching on the visual axis. HR-OCT showed normal thickness epithelial hyperreflectivity of involved cornea without stromal involvement, along with sharply demarcated borders of unaffected tissue. Histopathologic findings demonstrated vacuolated periodic acid-Schiff (PAS) positive cells throughout the epithelial layers consistent with LECD. CONCLUSIONS: HR-OCT was able to provide useful information to rule out ocular surface squamous neoplasia and confirm the clinical impression of LECD at the time of clinical examination. HR-OCT shows promise as an adjunctive diagnostic tool for ocular surface lesions and pathologies.