Spectral-domain Optical Coherence Tomography Images Research Articles

Enhancing the structure–function relationship in glaucoma using anatomical compensation of retinal nerve fibre layer

Background/aimsTo investigate whether compensating retinal nerve fibre layer (RNFL) thickness measurements for demographic and anatomical ocular factors can strengthen the structure–function relationship in patients with glaucoma.Methods600 eyes from 412 patients...

Intraoperative quantitative crystalline lens nuclear opacities analysis based on crystalline lenSx platform

PurposeThe main objective is to quantify the lens nuclear opacity using spectral-domain optical coherence tomography (SD-OCT) and to evaluate its association with Lens Opacities Classification System III (LOCS-III) system, lens thickness (LT), and surgical parameters. The secondary objective is to assess the diagnostic model performance for hard nuclear cataract.MethodsThis study included 70 eyes of 57 adults with cataract, with 49 (70%) and 21 (30%) in training and validation cohort, respectively. Correlations of the average nuclear density (AND) /maximum nuclear density (MND) with LOCS-III scores, LT, and surgical parameters were analyzed. Univariate and multivariate logistic regression analysis, receiver operating characteristic curves and calibration curves were performed for the diagnostic of hard nuclear cataract.ResultsThe pre-operative uncorrected distance visual acuity (UDVA), intraocular pressure (IOP), mean axial length (AL), and LT were 1.20 ± 0.47 log MAR, 15.50 ± 2.87 mmHg, 27.34 ± 3.77 mm and 4.32 ± 0.45 mm, respectively. The average nuclear opalescence (NO) and nuclear colour (NC) scores were 3.61 ± 0.94 and 3.50 ± 0.91 (ranging from 1.00 to 6.90), respectively. The average AND and MND were 137.94 ± 17.01 and 230.01 ± 8.91, respectively. NC and NO scores both significantly correlated with the AND (rNC = 0.733, p = 0.000; rNO = 0.755, p = 0.000) and MND (rNC = 0.643, p = 0.000; rNO = 0.634, p = 0.000). In the training cohort, the area under the curve (AUC) of the model was 0.769 (P < 0.001, 95%CI 0.620–0.919), which had a good degree of differentiation (Fig. 2a). The calibration curve showed good agreement between predicted and actual probability.ConclusionThe nuclear density measurement on SD-OCT images can serve as an objective and reliable indicator for quantifying nuclear density.

Optical coherence tomography choroidal enhancement using generative deep learning

Spectral-domain optical coherence tomography (SDOCT) is the gold standard of imaging the eye in clinics. Penetration depth with such devices is, however, limited and visualization of the choroid, which is essential for diagnosing chorioretinal disease, remains limited. Whereas swept-source OCT (SSOCT) devices allow for visualization of the choroid these instruments are expensive and availability in praxis is limited. We present an artificial intelligence (AI)-based solution to enhance the visualization of the choroid in OCT scans and allow for quantitative measurements of choroidal metrics using generative deep learning (DL). Synthetically enhanced SDOCT B-scans with improved choroidal visibility were generated, leveraging matching images to learn deep anatomical features during the training. Using a single-center tertiary eye care institution cohort comprising a total of 362 SDOCT-SSOCT paired subjects, we trained our model with 150,784 images from 410 healthy, 192 glaucoma, and 133 diabetic retinopathy eyes. An independent external test dataset of 37,376 images from 146 eyes was deployed to assess the authenticity and quality of the synthetically enhanced SDOCT images. Experts’ ability to differentiate real versus synthetic images was poor (47.5% accuracy). Measurements of choroidal thickness, area, volume, and vascularity index, from the reference SSOCT and synthetically enhanced SDOCT, showed high Pearson’s correlations of 0.97 [95% CI: 0.96–0.98], 0.97 [0.95–0.98], 0.95 [0.92–0.98], and 0.87 [0.83–0.91], with intra-class correlation values of 0.99 [0.98–0.99], 0.98 [0.98–0.99], and 0.95 [0.96–0.98], 0.93 [0.91–0.95], respectively. Thus, our DL generative model successfully generated realistic enhanced SDOCT data that is indistinguishable from SSOCT images providing improved visualization of the choroid. This technology enabled accurate measurements of choroidal metrics previously limited by the imaging depth constraints of SDOCT. The findings open new possibilities for utilizing affordable SDOCT devices in studying the choroid in both healthy and pathological conditions.

Longitudinal study of microphthalmia in connexin 50 knockout mice using spectral-domain optical coherence tomography

Connexin 50 (Cx50) mediated signaling is essential for controlling the lens growth and size. Cx50 mutations cause microphthalmia, smaller lenses, and cataracts in humans and animals. These ocular defects have never been investigated in live Cx50 mutant mice by using non-invasive imaging techniques. Here, we report a longitudinal study of the ocular defects in Cx50 knockout (Cx50KO) mice from the ages of 3 weeks to 12 months by using spectral-domain optical coherence tomography (SD-OCT). The anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL) were measured along the visual axis and adjusted with corresponding refractive indices. The SD-OCT image data confirm age-related reductions of LT and AL in live Cx50KO mice compared to age-matched wild-type (WT) controls, and the reduction values are comparable to the in vitro measurements of Cx50KO eyeballs and lenses reported previously. Moreover, reductions of ACD were observed in Cx50KO mice at all ages studied while VCD changes are statistically insignificant in comparison to the WT controls. Therefore, Cx50KO’s microphthalmia with small lens is selectively associated with delayed ACD development but not the vitreous formation. This work supports the notion that lens size and/or growth is important for anterior chamber development.

Quantifying Putative Retinal Gliosis in Preclinical Alzheimer's Disease.

Neuroinflammation plays a significant role in the pathology of Alzheimer's disease (AD). Mouse models of AD and postmortem biopsy of patients with AD reveal retinal glial activation comparable to central nervous system immunoreactivity. We hypothesized that the surface area of putative retinal gliosis observed in vivo using en face optical coherence tomography (OCT) imaging will be larger in patients with preclinical AD versus controls. The Spectralis II instrument was used to acquire macular centered 20 × 20 and 30 × 25-degrees spectral domain OCT images of 76 participants (132 eyes). A cohort of 22 patients with preclinical AD (40 eyes, mean age = 69 years, range = 60-80 years) and 20 control participants (32 eyes, mean age = 66 years, range = 58-82 years, P = 0.11) were included for the assessment of difference in surface area of putative retinal gliosis and retinal nerve fiber layer (RNFL) thickness. The surface area of putative retinal gliosis and RNFL thickness for the nine sectors of the Early Treatment Diabetic Retinopathy Study (ETDRS) map were compared between groups using generalized linear mixed models. The surface area of putative retinal gliosis was significantly greater in the preclinical AD group (0.97 ± 0.55 mm2) compared to controls (0.68 ± 0.40 mm2); F(1,70) = 4.41, P = 0.039; Cohen's d = 0.61. There was no significant difference between groups for RNFL thickness in the 9 ETDRS sectors, P > 0.05. Our analysis shows greater putative retinal gliosis in preclinical AD compared to controls. This demonstrates putative retinal gliosis as a potential biomarker for AD-related neuroinflammation.

Evaluating the Effect of Childhood Obesity on Choroidal Structures

Aim: To evaluate the effect of childhood obesity on choroidal structures with spectral-domain optical coherence tomography (SD-OCT). Material and Methods: A total of 80 children (20 children per each group; healthy, overweight, obese, and morbid-obese) were included in the study. Accompanying comorbidities such as insulin resistance, dyslipidemia, and metabolic syndrome were recorded. The subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) measurements were obtained from SD-OCT images and compared between groups. Results: No notable differences were found between groups regarding the means of age and axial length (p=0.504, and p=0.805, respectively). The SFCT medians (min-max) of healthy, overweight, obese, and morbid-obese children were 398.5 (319.0-453.5) μm, 299.0 (274.7-387.0) μm, 295.5 (257.0-385.0) μm, and 304.5 (272.2-386.0) μm respectively. Overweight and obese children had thinner choroid than non-obese healthy children (p=0.032). Besides, no significant correlation was observed between the severity of obesity and SFCT (p=0.722). In terms of CVI, total choroidal area, luminal area, and stromal area; no significant differences were found between groups (p=0.710, p=0.452, p=0.221, and p=0.863, respectively). Obese children with dyslipidemia had thinner SFCT than those not have dyslipidemia (292.0 (166-431)μm vs 348.0(173-491)μm, p=0.003), while insulin resistance and metabolic syndrome had no effect on SFCT (p=0.336, and p=0.211, respectively). Conclusion: Childhood obesity and accompanying dyslipidemia led to a decrease in SFCT without any significant change in the CVI. However, the severity of obesity and having insulin resistance or metabolic syndrome had no effect on either SFCT or CVI. The thinning in the SFCT may be related to microvascular disorders due to childhood obesity and dyslipidemia

Mirrored X-Net: Joint classification and contrastive learning for weakly supervised GA segmentation in SD-OCT

Deep learning achieves impressive performance in medical image segmentation, but the training phase requires a large amount of annotated data with precise clinical definitions. Weakly supervised lesion segmentation aims to produce pixel-level masks by learning discriminatory information from weak annotations. In this paper, Mirrored X-Net, a novel segmentation model only supervised by image-level category labels, is proposed to segment the Geographic Atrophy (GA) regions in en-face projection of Spectral-Domain Optical Coherence Tomography (SD-OCT) data. Characterized by the dimension-asymmetric information in SD-OCT images, a novel Anisotropic Downsampling (ADS) is proposed to augment feature shapes. To extract the regions of normal retina for both images with and without lesions, we propose a contrastive learning module to assimilate the deep representation of normal tissue in the SD-OCT images and improve the class-wise difference of deep representation. Based on the contrastive learning module, Anomalous Probability Map (APM) can be obtained to draw the distribution of difference with normal tissue in images. We jointly train the image classification and contrastive learning module, and the final GA segmentation is refined based on the en-face projection of APM. The experimental results on two independent GA datasets demonstrate that the proposed weakly supervised model can produce satisfactory results, and obtain even higher accuracy than fully supervised approaches. The source code is available at https://github.com/maxiao0234/Mirrored-X-Net-pytorch.

Deep-Learning-Based Group Pointwise Spatial Mapping of Structure to Function in Glaucoma

PurposeTo establish generalizable point-wise spatial relationship between structure and function through occlusion analysis of a deep-learning (DL) model for predicting the visual field (VF) sensitivities from three-dimensional (3D) optical coherence tomography (OCT) scan. DesignRetrospective cross-sectional study. Participants2151 eyes from 1129 patients. MethodsA DL model was trained to predict 52 VF sensitivities of 24-2 standard automated perimetry from 3D spectral-domain OCT images of the optic nerve head (ONH) with 12915 OCT-VF pairs. Using occlusion analysis, the contribution of each individual cube covering a 240 x 240 x 31.25 μm region of the ONH to the model's prediction was systematically evaluated for each OCT-VF pair in a separate test set that consisted of 996 OCT-VF pairs. After simple translation (shifting in x and y-axes to match the ONH center), group t-statistic maps were derived to visualize statistically significant ONH regions for each VF test point within a group. This analysis allowed for understanding the importance of each super voxel (240 x 240 x 31.25 μm covering the entire 4.32 x 4.32 x 1.125 mm ONH cube) in predicting VF test points for specific patient groups. Main Outcome MeasuresThe region at the ONH corresponding to each VF test point and the effect of the former on the latter. ResultsThe test set was divided to two groups, the healthy-to-early-glaucoma group (792 OCT-VF pairs, VF mean deviation (MD): -1.32 ± 1.90 dB) and the moderate-to-advanced-glaucoma group (204 OCT-VF pairs, VF MD: -17.93 ± 7.68 dB). Two-dimensional group t-statistic maps (x, y projection) were generated for both groups, assigning related ONH regions to visual field test points. The identified influential structural locations for VF sensitivity prediction at each test point aligned well with existing knowledge and understanding of structure-function spatial relationships. ConclusionsThis study successfully visualized the global trend of point-by-point spatial relationships between OCT-based structure and VF-based function without the need for prior knowledge or segmentation of OCTs. The revealed spatial correlations were consistent with previously published mappings. This presents possibilities of learning from trained machine learning models without applying any prior knowledge, potentially robust and free from bias.

Adaptive Optics Retinal Imaging in RDH12-Associated Early Onset Severe Retinal Dystrophy.

RDH12 is among the most common genes found in individuals with early-onset severe retinal (EOSRD). Adaptive optics scanning light ophthalmoscopy (AOSLO) enables resolution of individual rod and cone photoreceptors in the retina. This study presents the first AOSLO imaging of individuals with RDH12-associated EOSRD. Case series of patients who attended Moorfields Eye Hospital (London, UK). Spectral-domain optical coherence tomography, near-infrared reflectance (NIR), and blue autofluorescence imaging were analyzed. En face image sequences of photoreceptors were recorded using either of two AOSLO modalities. Cross-sectional analysis was undertaken for seven patients and longitudinal analysis for one patient. Nine eyes from eight patients are presented in this case series. The mean age at the time of the assessment was 11.2 ± 6.5years of age (range 7-29). A subfoveal continuous ellipsoid zone (EZ) line was present in eight eyes. Posterior pole AOSLO revealed patches of cone mosaics. Average cone densities at regions of interest 0.5° to the fovea ranged from 12,620 to 23,660 cells/mm2, whereas intercell spacing ranged from 7.0 to 9.7µm. This study demonstrates that AOSLO can provide useful high-quality images in patients with EOSRD, even during childhood, with nystagmus, and early macular atrophy. Cones at the posterior pole can appear as scattered islands or, possibly later in life, as a single subfoveal conglomerate. Detailed image analysis suggests that retinal pigment epithelial stress and dysfunction may be the initial step toward degeneration, with NIR being a useful tool to assess retinal well-being in RDH12-associated EOSRD.

A comparative study of cystoid macula edema following glaucoma drainage device surgery versus trabeculectomy

PurposeTo assess and compare the risk for development of cystoid macula edema (CME) after glaucoma drainage device (GDD) implantation versus conventional trabeculectomy with mitomycin (trab) for glaucoma.MethodsRetrospective review of consecutive patients receiving trab or GDD implantation between 2016 and 2018. Inclusion criteria were availability of pre- and postoperative spectral domain optical coherence tomography (SD-OCT) of the macula. SD-OCT images were evaluated for presence of CME qualitatively, central subfield thickness (CST) and macular volume (MV).Results73 eyes could be included, 42 received trab and 31 GDD surgery. Eyes receiving trab on average had 0.8 ± 0.8 previous intraocular operations, while eyes with GDD implantation had 3.1 ± 1.9 (p < 0.001). Occurrence of postoperative CME was significantly more frequent after GDD implantation (6 out of 31 (19.4%)) than after trab (2 out of 42 eyes = 4.8%), (p = 0.049). Mean preoperative CST as well as MV was comparable in both groups (CST before trab: 282.7 ± 23.0 µm, CST before GDD 284.2 ± 27.3 µm, p = 0.287; MV before trab: 7.8 ± 1.1 mm3, MV before GDD: 8.0 ± 0.8mm3, p = 0.305). Mean postoperative CST and MV were significantly higher after GDD (CST 338.5 ± 129.3 µm, MV 8.8 ± 2.6 mm3) than after trabeculectomy (CST 290.6 ± 60.2 µm, p = 0.038; MV 7.8 ± 1.2mm3, p = 0.039).ConclusionsIn real-life conditions, GDD surgery seems to be associated with a higher risk to develop CME when compared to conventional trabeculectomy. This information may be helpful for glaucoma surgeons to advise the patients on postoperative risks of surgery.

Evaluation of Optic Nerve Head Microcirculation in Open-Angle Glaucoma Patients with Unilateral Visual Field Defect.

Microcirculation of optic nerve head (ONH) in open-angle glaucoma (OAG) patients with unilateral visual field (VF) loss has yet to be fully investigated, especially the perimetrically unaffected fellow eyes. Thirty-eight OAG patients with VF defect in one eye and normal VF in the other eye, and thirty-one healthy participants were analyzed. All participants underwent laser speckle flowgraphy (LSFG), spectral-domain optical coherence tomography (SD-OCT) imaging, and VF test for further analyses. LSFG measurements included mean blur rate in all area of ONH (MA), big vessel area of ONH (MV), and tissue area of ONH (MT). SD-OCT parameters included circumpapillary retinal nerve fiber layer (cpRNFL) thickness and macula thicknesses. The difference of LSFG and SD-OCT indices between glaucoma patients and healthy controls were compared. The diagnostic accuracy was analyzed with the areas under the receiver operating characteristic curves (AROCs). Global cpRNFL thickness and macular thickness in unaffected eyes of OAG patients were higher than their fellow eyes and lower than healthy eyes. MA and MV in healthy eyes and unaffected eyes were significantly higher than in affected eyes. MT in unaffected eyes of OAG patients was higher than in their fellow affected eyes but lower than in healthy eyes. The AROCs were highest for cpRNFL (0.925), followed by macular thickness (0.838), and MT (0.834). ONH microcirculation in perimetrically unaffected fellow eyes was decreased in OAG patients with unilateral VF loss. LSFG can detect changes of ONH in high-risk eyes before detectable VF damage, which may reflect the vascular pathophysiology for glaucoma.

Artificial intelligence for the detection of glaucoma with SD-OCT images: a systematic review and Meta-analysis.

To quantify the performance of artificial intelligence (AI) in detecting glaucoma with spectral-domain optical coherence tomography (SD-OCT) images. Electronic databases including PubMed, Embase, Scopus, ScienceDirect, ProQuest and Cochrane Library were searched before May 31, 2023 which adopted AI for glaucoma detection with SD-OCT images. All pieces of the literature were screened and extracted by two investigators. Meta-analysis, Meta-regression, subgroup, and publication of bias were conducted by Stata16.0. The risk of bias assessment was performed in Revman5.4 using the QUADAS-2 tool. Twenty studies and 51 models were selected for systematic review and Meta-analysis. The pooled sensitivity and specificity were 0.91 (95%CI: 0.86-0.94, I2=94.67%), 0.90 (95%CI: 0.87-0.92, I2=89.24%). The pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 8.79 (95%CI: 6.93-11.15, I2=89.31%) and 0.11 (95%CI: 0.07-0.16, I2=95.25%). The pooled diagnostic odds ratio (DOR) and area under curve (AUC) were 83.58 (95%CI: 47.15-148.15, I2=100%) and 0.95 (95%CI: 0.93-0.97). There was no threshold effect (Spearman correlation coefficient=0.22, P>0.05). There is a high accuracy for the detection of glaucoma with AI with SD-OCT images. The application of AI-based algorithms allows together with "doctor+artificial intelligence" to improve the diagnosis of glaucoma.

Optical coherence tomography biomarkers DROL, PROS, SND, hyperreflective walls of foveal cystoid spaces as predictors of central macular thickness and visual acuity in diabetic macular edema treated with intravitreal ranibizumab.

This study aims to establish DROL (disruption of retinal outer layers), PROS (photoreceptor outer segment length), SND (subfoveal neuroretinal detachment), and hyperreflective walls of foveal cystoid spaces (HRW) as optical coherence tomography (OCT) biomarkers and predictors of central macular thickness (CMT) and visual acuity in diabetic macular edema (DME) treated with intravitreal ranibizumab (IVR). In this prospective, interventional study performed at a tertiary care center over a span of 1 year from December 2021 to December 2022, 50 eyes of 46 patients of DME were included. Visual acuity and spectral domain OCT imaging were performed at baseline. Using inbuilt calipers on SD-OCT, the horizontal extent of DROL and the vertical extent of PROS were measured manually. SND and HRW were assessed qualitatively. IVR was administered and patients were followed up at 4, 8, and 12 weeks. The eyes without DROL had statistically significant (P < 0.05) lesser CMT and better BCVA (best-corrected visual acuity) (P < 0.05) after pro re nata injection of IVR. There was a positive correlation between the extent of baseline DROL with final CMT (P < 0.05) and final logMAR BCVA (P > 0.05), whereas negative correlation with the extent of baseline PROS with final CMT (P < 0.05) and final logMAR BCVA (P > 0.05). The presence of HRW and SND predicted non-resolution of CMT and worse visual acuity after treatment with IVR in DME. DROL, PROS, SND, and hyperreflective walls of foveal cystoid spaces may be utilized as qualitative as well as quantitative biomarkers to predict the post-treatment CMT and visual acuity in DME.

GCN-assisted attention-guided UNet for automated retinal OCT segmentation

With the increase in the aging population of many countries, the prevalence of neovascular age-related macular degeneration (nAMD) is expected to increase. Morphological parameters such as intraretinal fluid (IRF), subretinal fluid (SRF), subretinal hyperreflective material (SHRM), and pigment epithelium detachment (PED) of spectral-domain optical coherence tomography (SD-OCT) images are vital markers for proper treatment of nAMD, especially to get the information of treatment response to determine the proper treatment interval and switching of anti-vascular endothelial growth factor (VEGF) agents. For the precise evaluation of the change in nAMD lesions and patient-specific treatment, quantitative evaluation of the lesions in the OCT volume scans is necessary. However, manual segmentation requires many resources, and the number of studies of automatic segmentation is increasing rapidly. Improving automated segmentation performance in SD-OCT visual results requires long-range contextual inference of spatial information between retinal lesions and layers. This paper proposes a GAGUNet (graph convolution network (GCN)-assisted attention-guided UNet) model with a novel global reasoning module considering these points. The dataset used in the main experiment of this study underwent rigorous review by a retinal specialist from Konkuk University Hospital in Korea, contributing to both data preprocessing and validation to ensure a qualitative assessment. We conducted experiments on the RETOUCH dataset as well to demonstrate the scalability of the proposed model. Overall, our model demonstrates superior performance over the baseline models in both quantitative and qualitative evaluations.

Distinct Clinical Effects of Two RP1L1 Hotspots in East Asian Patients With Occult Macular Dystrophy (Miyake Disease): EAOMD Report 4.

To characterize the clinical effects of two RP1L1 hotspots in patients with East Asian occult macular dystrophy (OMD). Fifty-one patients diagnosed with OMD harboring monoallelic pathogenic RP1L1 variants (Miyake disease) from Japan, South Korea, and China were enrolled. Patients were classified into two genotype groups: group A, p.R45W, and group B, missense variants located between amino acids (aa) 1196 and 1201. The clinical parameters of the two genotypes were compared, and deep learning based on spectral-domain optical coherence tomographic (SD-OCT) images was used to distinguish the morphologic differences. Groups A and B included 29 and 22 patients, respectively. The median age of onset in groups A and B was 14.0 and 40.0 years, respectively. The median logMAR visual acuity of groups A and B was 0.70 and 0.51, respectively, and the survival curve analysis revealed a 15-year difference in vision loss (logMAR 0.22). A statistically significant difference was observed in the visual field classification, but no significant difference was found in the multifocal electroretinographic classification. High accuracy (75.4%) was achieved in classifying genotype groups based on SD-OCT images using machine learning. Distinct clinical severities and morphologic phenotypes supported by artificial intelligence-based classification were derived from the two investigated RP1L1 hotspots: a more severe phenotype (p.R45W) and a milder phenotype (1196-1201 aa). This newly identified genotype-phenotype association will be valuable for medical care and the design of therapeutic trials.

Closure Grading and Visual Outcome in Patients with Large Idiopathic Macular Holes: A Spectral-Domain Optical Coherence Tomography Observation.

So far, there has been no closure grade system synthesizing morphological and microstructural features for large idiopathic macular holes (IMHs) treated by vitrectomy and internal limiting membrane (ILM) peeling. This study aims to propose a concise one and explore its relevance with visual acuity and the related preoperative factors. Consecutive patients with large IMHs (minimum diameter > 400μm), undergoing vitrectomy and ILM peeling, obtaining primary closure and regularly followed-up were enrolled. Preoperative clinical charts and spectral-domain optical coherence tomography (SD-OCT) parameters were reviewed. SD-OCT images and best-corrected visual acuity (BCVA) were assessed at 1, 4, and 10 months postoperatively. SD-OCT features at last visit were categorized by BCVA significance, and preoperative risk factors were analysed. Sixty-eight eyes from 64 patients were enrolled. The 10-month postoperative SD-OCT images were categorized into closure Grade 1, 2, and 3 with successively decreased BCVA (P<0.001). During early follow-up, part of Grades 2 and 3 could evolve into the upper grade respectively, but Grade 3 could never evolve into Grade 1 and exhibited the least satisfactory long-term BCVA. Binary logistic regression showed that large minimum linear diameter (MLD) was a risk factor for Grade 3 occurrence (P<0.001), with a cut-off value of 625.5μm from the receiver operating characteristic curve for MLD predicting Grade 3 occurrence (P=0.001). Long-term closure status of large IMHs could be categorized into three grades with BCVA significance. Large horizontal MLD is a risk factor for occurrence of Grade 3 closure with unsatisfactory visual recovery.

SD-OCT Imaging of Macular Changes in Fabry Disease: A Case Report

ABSTRACT Fabry disease (FD) is a rare, X-linked lysosomal storage disorder that can result in fatal end-stage renal disease, heart failure, and cerebro-occlusive events. Vague clinical symptoms and rarity often mean diagnosis and potential treatment is delayed. Ophthalmic findings in FD patients can be helpful in establishing an early diagnosis and timely treatment. Spectral domain optical coherence tomography (SD-OCT) imaging in FD patients shows hyper-reflective foci (HRF) in characteristic patterns within the inner retinal layers. We found that the HRF was localised in linear distributions at the deep and superficial borders of the retinal inner nuclear layer, likely reflecting anatomic vascular plexuses and FD-related sphingolipid deposition within the vessel walls. These results highlight the potential use of SD-OCT in FD and how it may aid diagnosis in undifferentiated patients, prognostication, and disease monitoring.

Mutational Profile and Retinal Phenotypes of PCARE-Related Cone-Rod Dystrophies in a Mexican Cohort.

The aim of the study is to describe the genotype and phenotype of a Mexican cohort with PCARE-related retinal disease. The study included 14 patients from 11 unrelated pedigrees with retinal dystrophies who were demonstrated to carry biallelic pathogenic variants in PCARE. Visual assessment methods included best corrected visual acuity, color fundus photography, Goldmann visual field test, kinetic perimetry, dark/light adapted chromatic perimetry, full-field electroretinography, autofluorescence imaging, and spectral domain-optical coherence tomography imaging. Genetic screening was performed either by gene panel sequencing or by exome sequencing. According to the results of multimodal imaging and functional tests, all 14 patients were diagnosed with cone-rod dystrophy. Six different PCARE pathogenic alleles were identified in our cohort, including three novel mutations: c.3048_3049del (p.Tyr1016∗), c.3314_3315del (p.Ser1105∗), and c.551A > G (p.His184Arg). Notably, alleles p.His184Arg, p.Arg613∗, and p.Arg984∗ were present in 18 of the 22 (82%) PCARE alleles from probands in our cohort. Our work expands the PCARE mutational profile by identifying three novel pathogenic variants causing retinal dystrophy. While phenotypic variations occurred among patients, a cone-rod dystrophy pattern was observed in all affected individuals.

Morphometric Risk Factors for Drusenoid Pigment Epithelium Detachment Collapse and Retinal Pigment Epithelium Atrophy Expansion.

The purpose of this study was to investigate factors associated with drusenoid pigment epithelium detachment (dPED) growth rate, incidence of dPED collapse, and retinal pigment epithelium (RPE) atrophy enlargement rate following dPED collapse and their impact on visual acuity (VA). This was a retrospective longitudinal study on 44 eyes. Serial spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (AF) imaging were performed. Qualitative features and quantitative dPED-related metrics were assessed. The surface-to-volume ratio (S/V) was computed to evaluate dPED shape irregularity. AF imaging was utilized to measure RPE atrophy area in eyes experiencing dPED collapse. Regression models were used to analyze associations among VA, dPED growth rate, and RPE atrophy enlargement rate. Cox regression was used to identify risk factors for dPED collapse. Significant correlations were observed between dPED area, surface, and volume (P < 0.05 for all pairs). The dPED metrics were inversely correlated with the S/V. Incidence of dPED collapse was 22 per 100 eye-years over a mean follow-up of 59 ± 41 months. Eyes experiencing collapsed dPED had worse baseline VA (P < 0.001). RPE hypertransmission (hazard ratio [HR] = 3.68, P = 0.004) and hyper-reflective foci (HR = 3.45, P = 0.02) were risk factors for dPED collapse; a higher S/V ratio was protective (HR = 0.78, P = 0.03). A faster rate of RPE atrophy enlargement was associated with a faster rate of dPED volume increase (r = 0.47, P = 0.02) and worse VA over time (P = 0.02). Risk stratification in patients with dPED can be aided by identifying risk factors for dPED collapse. Identifying factors associated with RPE atrophy enlargement may have implications for treatment decision making.

Macular choroidal thickness, volume, and vascularity index in patients with systemic sclerosis.

The aim of this study was to investigate choroidal parameters in patients with systemic sclerosis (SSc) using enhanced depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT) and to determine their relationships with clinical variables and ocular features. Thirty-three patients with SSc and 40 controls were enrolled. The groups did not differ with regard to age, sex, and axial length. The mean choroidal thickness and volume were obtained in each conventional Early Treatment of Diabetic Retinopathy Study grid subfield. The choroidal vascularity index (CVI), which provides a quantitative analysis of vasculature by calculating the proportion of the luminal area (LA) to the total choroidal area (TCA), was determined. Lower choroidal thickness and volume were observed in the SSc group. The CVI was significantly higher in SSc patients, whereas the TCA, LA, and stromal area were significantly lower in the SSc group; however, the significant difference of the stromal component was more pronounced than that of the luminal component. Regression analyses did not identify any clinical factors associated with the CVI (except Ca-blocker use), central macular thickness, or volume. No significant differences in choroidal parameters were found within the SSc subtypes (diffuse cutaneous systemic sclerosis (dcSSc) vs. limited cutaneous systemic sclerosis (lcSSc)), or between eyes stratified according to SSc pattern (early, active, or late) using nailfold capillaroscopy (p > 0.05 for all). Our results, with notably higher CVI values, may shed new light on choroidal impairment in patients with SSc. Stromal involvement appeared to dominate the vascular component.