Optical Coherence Tomography Angiography Research Articles

Differential Artery–Vein Analysis Improves OCTA Classification of Diabetic Retinopathy

This study investigates the impact of differential artery-vein (AV) analysis in optical coherence tomography angiography (OCTA) on machine learning classification of diabetic retinopathy (DR). Leveraging deep learning for arterial-venous area (AVA) segmentation, six quantitative features, including perfusion intensity density (PID), blood vessel density (BVD), vessel area flux (VAF), blood vessel caliber (BVC), blood vessel tortuosity (BVT), and vessel perimeter index (VPI) features, were derived from OCTA images before and after AV differentiation. A support vector machine (SVM) classifier was utilized to assess both binary and multiclass classifications of control, diabetic patients without DR (NoDR), mild DR, moderate DR, and severe DR groups. Initially, one-region features, i.e., quantitative features extracted from the entire OCTA, were evaluated for DR classification. Differential AV analysis improved classification accuracies from 78.86% to 87.63% and from 79.62% to 85.66% for binary and multiclass classifications, respectively. Additionally, three-region features derived from the entire image, parafovea, and perifovea, were incorporated for DR classification. Differential AV analysis further enhanced classification accuracies from 84.43% to 93.33% and from 83.40% to 89.25% for binary and multiclass classifications, respectively. These findings highlight the potential of differential AV analysis in augmenting disease diagnosis and treatment assessment using OCTA.

Repeatability, interocular correlation and agreement of optic nerve head vessel density in healthy eyes: a swept-source optical coherence tomographic angiography study.

To assess the repeatability, interocular correlation, and agreement of quantitative swept-source optical coherence tomography angiography (OCTA) optic nerve head (ONH) parameters in healthy subjects. Thirty-three healthy subjects were enrolled. The ONH of both eyes were imaged four times by a swept-source-OCTA using a 3 mm ×3 mm scanning protocol. Images of the radial peripapillary capillary were analyzed by a customized Matlab program, and the vessel density, fractal dimension, and vessel diameter index were measured. The repeatability of the four scans was determined by the intraclass correlation coefficient (ICC). The most well-centered optic disc from the four repeated scans was then selected for the interocular correlation and agreement analysis using the Pearson correlation coefficient, ICC and Bland-Altman plots. All swept-source-OCTA ONH parameters exhibited certain repeatability, with ICC>0.760 and coefficient of variation (CoV)≤7.301%. The obvious interocular correlation was observed for papillary vessel density (ICC=0.857), vessel diameter index (ICC=0.857) and fractal dimension (ICC=0.906), while circumpapillary vessel density exhibited moderate interocular correlation (ICC=0.687). Bland-Altman plots revealed an agreement range of -5.26% to 6.21% for circumpapillary vessel density. OCTA ONH parameters demonstrate good repeatability in healthy subjects. The interocular correlations of papillary vessel density, fractal dimension and vessel diameter index are high, but the correlation for circumpapillary vessel density is moderate.

Choriocapillaris reduction accurately discriminates against early-onset Alzheimer's disease.

This study addresses the urgent need for non-invasive early-onset Alzheimer's disease (EOAD) prediction. Using optical coherence tomography angiography (OCTA), we present a choriocapillaris model sensitive to EOAD, correlating with serum biomarkers. Eighty-four EOAD patients and 73 controls were assigned to swept-source OCTA (SS-OCTA) or the spectral domain OCTA (SD-OCTA) cohorts. Our hypothesis on choriocapillaris predictive potential in EOAD was tested and validated in these two cohorts. Both cohorts revealed diminished choriocapillaris signals, demonstrating the highest discriminatory capability (area under the receiver operating characteristic curve: SS-OCTA 0.913, SD-OCTA 0.991; P<0.001). A sparser SS-OCTA choriocapillaris correlated with increased serum amyloid beta (Aβ)42, Aβ42/40, and phosphorylated tau (p-tau)181 levels (all P<0.05). Apolipoprotein E status did not affect choriocapillaris measurement. The choriocapillaris, observed in both cohorts, proves sensitive to EOAD diagnosis, and correlates with serum Aβ and p-tau181 levels, suggesting its potential as a diagnostic tool for identifying and tracking microvascular changes in EOAD. Optical coherence tomography angiography may be applied for non-invasive screening of Alzheimer's disease (AD). Choriocapillaris demonstrates high sensitivity and specificity for early-onset AD diagnosis. Microvascular dynamics abnormalities are associated with AD.

Circulatory Failure in the Central Retinal Artery during Medial Orbital Wall Blow-out Fracture Repair

Purpose: We report a case of visual impairment due to circulatory failure in the central retinal artery during blow-out fracture repair.Case summary: A 16-year-old male with no underlying disease was diagnosed with a trapdoor type medial orbital wall blow-out fracture after a motorcycle accident and underwent blow-out fracture repair. During the surgery, his left eye was nearly completely dilated. Postoperatively, the visual acuity in the left eye was hand motion and there was ptosis of the left upper eyelid. Concerned with the possibility of orbital implant compression, computed tomography was performed immediately and a second operation was performed. However, there was no direct compression originating from the intraocular implant or any signs of active bleeding. The following day, optical coherence tomography and fluorescein angiography revealed a cherry-red spot on the central fovea with edema of the inner retinal layer and delayed arterial circulation. Under a diagnosis of incomplete central retinal artery occlusion, the patient was treated with intraocular pressure-lowering eye drops and intravenous mannitol. Despite prompt intervention, the visual acuity of the left eye did not improve beyond 0.04 at the 2-year follow-up.Conclusions: When there is visual impairment and pupillary dilation after blow-out fracture repair, we should consider not only compressive factors but also the possibility of central retinal artery occlusion or circulatory failure. In such cases, retinal examinations should be done to assess the retinal blood flow and enable early detection of any complications allowing prompt appropriate intervention.

Optical coherence tomography angiography suggests different retinal pathologies in multiple sclerosis and Sjögren's syndrome.

While retinal vessel changes are evident in the eyes of patients with relapsing-remitting multiple sclerosis (RRMS), changes in the vasculature of possible MS mimics such as primary Sjögren's syndrome (pSS) remain to be determined. We investigated the potential of retinal optical coherence tomography (OCT) angiography (OCTA) as diagnostic tool to differentiate between patients with RRMS and pSS. This cross-sectional study included patients with RRMS (n = 36), pSS (n = 36) and healthy controls (n = 30). Participants underwent clinical examination, assessment of visual acuity, retinal OCT, OCTA, and serum markers of glial and neuronal damage. We investigated the associations between OCTA parameters, visual functions, and serum markers. Eyes with a history of optic neuritis (ON) were excluded from analysis. We observed a significant thinning of the combined ganglion cell and inner plexiform layer in the eyes of patients with RRMS but not with pSS, when compared to healthy controls. Retinal vessel densities of the superficial vascular complex (SVC) were reduced in both patients with RRMS and pSS. However, retinal vessel rarefication of the deep vascular complex (DVC) was only evident in patients with pSS but not RRMS. Using multivariate regression analysis, we found that DVC vessel loss in pSS patients was associated with worse visual acuity. Compared to patients with RRMS, rarefication of deep retinal vessels is a unique characteristic of pSS and associated with worse visual function. Assuming a disease-specific retinal vessel pathology, these data are indicative of a differential affliction of the gliovascular complex in the retina of RRMS and pSS patients.

Correlation between vessel density and thickness in the retina and choroid of severe non-proliferative diabetic retinopathy patients

ObjectivesTo explore the correlation between the vessel density (VD) of the retina and choroid vascular plexuses and the thicknesses of their respective retinal layers and choroid membranes in participants with severe non-proliferative diabetic retinopathy (NPDR).MethodsWe retrospectively analyzed the data of 42 eyes of 42 participants with diabetes mellitus (DM) and severe NPDR. In addition, 41 eyes of 41 healthy controls were evaluated. Measurements were taken for both groups using optical coherence tomography angiography (OCTA), including the area and perimeter of the foveal vascular zone (FAZ) and the vascular density (VD) in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choroid capillary (CC). These measurements were compared with the retinal thickness (RT) of the inner/intermediate retinal layers and choroidal thickness (CT). The study evaluated the correlation between RT or CT and VD in the respective vascular networks, namely superficial capillary plexus (SCP), deep capillary plexus (DCP), or CC.ResultsThe inner RT and VD in all plexuses were significantly lower in the severe NPDR group than in the healthy controls. Furthermore, the FAZ area and perimeter were larger in the severe NPDR group. Inner RT was correlated with VD in the SCP group (r=0.67 and r=0.71 in the healthy control and severe NPDR groups, respectively; p&amp;lt;0.05). CT negatively correlated with VD in the CC (r=-0.697 and r=-0.759 in the healthy control and severe NPDR groups, respectively; p&amp;lt;0.05). Intermediate RT significantly correlated with VD in the DCP of the severe NPDR group (r=-0.55, p&amp;lt;0.05), but not in the healthy control group.ConclusionsRetinal or choroidal thickness strongly correlated with VD. Therefore, patients with severe NPDR must consider the distinct anatomical and functional entities of the various retinal layers and the choroid.

Unveiling the retinal secrets of neuromyelitis optica spectrum disorder

BackgroundVascular alterations are now recognized as important contributors to the pathophysiology of neuromyelitis optica spectrum disorder (NMOSD). This study aimed to use optical coherence tomography (OCT) and OCT-angiography (OCTA) to assess alterations in the retinal structure and microvasculature in patients with NMOSD, so we can understand pathophysiology of NMOSD, implicating this on disease activity, visual outcome and management on the future.MethodsA case–control study was conducted on 40 NMOSD patients with (NMOSD + ON) and without (NMOSD – ON) history of optic neuritis and 36 healthy subjects. The following data were assessed in NMOSD patients: clinical history, EDSS, and visual function testing. Both groups underwent spectral domain (SD)-OCT and OCTA.ResultsIn this study, NMOSD + ON patients had a statistically significant reduction in all SD-OCT parameters compared to healthy control. Regarding OCTA, there was a significant reduction in radial peripapillary capillary density (RPCD) in NMOSD + ON (P-value < 0.001) and some sectors of NMOSD–ON compared to healthy control. NMOSD + ON patients had significant differences in RPCD compared to those without (P-value < 0.001).ConclusionsHere we show that the advance of this study is that retinal microvascular alterations have been noticed in NMOSD–ON eyes, indicating that subclinical primary retinal vasculopathy and disease activity may occur in NMOSD before onset of ON and retinal atrophy. This may have implications on early detection of disease activity, early interference in management and prognostic tool to visual outcome in following the patients.

Choroidal thickness and retinal vascular changes in patients with lichen planus: an inflammatory disease beyond the skin.

Lichen planus (LP) is a common inflammatory condition of unknown etiology that commonly affects the skin and mucous membranes. Optical coherence tomography angiography (OCTA) is a noninvasive technique for identifying early retinal vascular impairment in systemic disease without clinical damage by imaging deep and superficial capillary networks. To assess the impacts of LP on the choroid and assess vascular changes in retinal capillary density using OCTA. This single-center prospective case-control study included 30 therapeutic-naïve LP patients and 30 age and sex-matched healthy individuals. All study subjects underwent a complete ophthalmological examination, including best-corrected visual acuity (BCVA) measurement using a Snellen chart, slit-lamp biomicroscopy, intraocular pressure (IOP) measurement, and fundus examination. They were then examined using spectral domain OCT and choroidal thickness was measured. The vessel density of the superficial and deep capillary networks was measured and assessed using OCTA. Patients had significantly thicker choroidal and retinal thickness than controls, with subfoveal, nasal, and temporal areas showing a significant difference. A significantly higher vascular density in the superficial capillary plexus, particularly in the nasal perifoveal area, was found compared to the control group. Significantly, higher vascular density in the deep capillary plexus in the parafoveal area compared to controls was reported. Significant correlations were found between visual acuity and IOP, and age, duration of disease, and severity of disease. This study is the first to reveal that LP patients exhibit choroidal changes and retinal vascular alterations compared to healthy controls.

Improved accuracy of spectral-domain optical coherence tomography and optical coherence tomography angiography for monitoring myopic macular neovascularisation activity

Background/aimsTo evaluate the diagnostic accuracy of spectral-domain optical coherence tomography (SD OCT) combined with OCT angiography (OCTA) for myopic myopic macular neovascularisation (MNV) activity.MethodsBoth eyes of patients with myopic MNV...

Race/Ethnicity Analysis of Vascular Alterations in Optical Coherence Tomography Angiography in Diabetic Patients

ABSTRACT Purpose Racial and ethnic minorities have a higher prevalence of diabetic retinopathy (DR) and present at advanced stages of disease. In an urban hospital population, we investigated microvascular differences in optical coherence tomography angiography (OCTA) between racial/ethnic groups while adjusting for socioeconomic status (SES). Methods 3 × 3 mm2 macular OCTA scans were obtained for analysis of foveal avascular zone (FAZ) area, FAZ perimeter as well as superficial (SCP) and deep capillary plexus (DCP) vessel density (VD), vessel length density (VLD), and adjusted flow index (AFI). SES was measured using the Area Deprivation Index. Multivariable regression models were used to adjust estimates for relevant confounders. Results 217 non-diabetic and 1,809 diabetic patients were included in the study, consisting of 42.2% Hispanic, 24.9% non-Hispanic (NH) Asian, 6.8% NH Black, 9.7% NH White and 16.3% Other patients. NH White was used as the reference group. Hispanic, NH Asian, and NH Black patients had significantly greater FAZ areas and FAZ perimeters, and lower DCP VD and VLD, among both non-diabetic and diabetic patients (Benjamini-Hochberg adjusted P-values <0.05). The addition of SES scores in the models did not modify any regressions significantly. Conclusions In patients with and without diabetes, racial and ethnic minorities have significant retinal microvasculature differences when compared to NH White patients, regardless of SES. These differences are pronounced in DCP and may predispose racial/ethnic minorities to worse outcomes in DR, thus widening disparities in ophthalmic care.

Impact of Solar Eclipses on Vision: Insights from Optical Coherence Tomography and Optical Coherence Tomography Angiography Analysis*

Purpose Solar retinopathy, resulting from solar eclipse exposure, poses risks to visual health. This study explores acute and chronic phase findings using clinical examinations and optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A) with a focus on longitudinal assessment. Methods Seven eyes with a history of unprotected solar eclipse exposure were included. Clinical examination, fundus photography, OCT, and OCT-A imaging were performed at initial assessment, as well as at one-month and six-month follow-up intervals. Data analysis included descriptive statistics. Results The cases, exposed without protection, underwent assessments, revealing variable visual acuity, outer retinal layer, and Henle fiber layer changes during follow-up. Regression of hyperreflectivity within the outer retinal and Henle fiber layers was observed over time in all eyes, although persistent microdefects within the outer retinal layer were noted in specific cases. OCT-A imaging revealed a larger foveal avascular zone, which persisted over a six-month period in select cases. Additionally, affected eyes exhibited a decrease in superficial vascular density, with subsequent improvement noted during the six-month period. Conclusion Solar retinopathy can result in visual impairment, accompanied by alterations observed in the Henle fiber layer using OCT. Additionally, OCT-A findings indicate possible vascular involvement. This study underscores the significance of adopting protective measures during solar eclipses and emphasizes the value of employing longitudinal multimodal imaging techniques to comprehend the pathophysiology of the condition.

Deep learning-driven automated quality assessment of ultra-widefield optical coherence tomography angiography images for diabetic retinopathy

AbstractImage quality assessment (IQA) of fundus images constitutes a foundational step in automated disease analysis. This process is pivotal in supporting the automation of screening, diagnosis, follow-up, and related academic research for diabetic retinopathy (DR). This study introduced a deep learning-based approach for IQA of ultra-widefield optical coherence tomography angiography (UW-OCTA) images of patients with DR. Given the novelty of ultra-widefield technology, its limited prevalence, the high costs associated with equipment and operational training, and concerns regarding ethics and patient privacy, UW-OCTA datasets are notably scarce. To address this, we initially pre-train a vision transformer (ViT) model on a dataset comprising 6 mm × 6 mm OCTA images, enabling the model to acquire a fundamental understanding of OCTA image characteristics and quality indicators. Subsequent fine-tuning on 12 mm × 12 mm UW-OCTA images aims to enhance accuracy in quality assessment. This transfer learning strategy leverages the generic features learned during pre-training and adjusts the model to evaluate UW-OCTA image quality effectively. Experimental results demonstrate that our proposed method achieves superior performance compared to ResNet18, ResNet34, and ResNet50, with an AUC of 0.9026 and a Kappa value of 0.7310. Additionally, ablation studies, including the omission of pre-training on 6 mm × 6 mm OCTA images and the substitution of the backbone network with the ViT base version, resulted in varying degrees of decline in AUC and Kappa values, confirming the efficacy of each module within our methodology.

Relationship between macular perfusion and lesion distribution in diabetic retinopathy.

To assess the relationship between macular vessel density metrics and foveal avascular zone (FAZ) characteristics on optical coherence tomography angiography (OCTA) and lesion distribution in eyes with diabetic retinopathy (DR). Patients with DR who underwent both Optos ultrawidefield (UWF) pseudocolor imaging and macular OCTA (Cirrus Angioplex, 6 × 6 mm) were included in this cross-sectional observational study. The distribution of DR lesions was assessed by comparing each of the peripheral ETDRS extended fields (3-7) against their corresponding ETDRS field, hence eyes were defined as either having predominantly peripheral lesions (PPL) or predominantly central lesions (PCL). En face OCTA images from the superficial and deep capillary plexuses (SCP and DCP) were then analysed using Image J software. Perfusion density (PD), vessel length density (VLD), and fractal dimensions (FD) were calculated following binarization and skeletonization of the images. Out of 344 eyes, 116 (33.72%) eyes had PPL and 228 (66.28%) eyes had PCL. For all DRSS levels, VLD, PD, and FD were not significantly different between eyes with PPL and PCL. The FAZ in eyes with PPL, however, was found to be more circular in shape compared to eyes with PCL (p = 0.037). Although the presence of PPL has been associated with a higher risk for diabetic retinopathy progression, the macular perfusion is similar in eyes with PPL and PCL. The FAZ is more circular in eyes with PPL, but the clinical relevance of this difference remains to be defined.

Discriminating Glioblastoma from Normal Brain Tissue In Vivo Using Optical Coherence Tomography and Angiography: A Texture and Microvascular Analysis Approach

Brain tumors arise from abnormal cell growth in the brain. Glioblastoma, the most common and aggressive type, poses significant challenges for identification during surgery. The primary goal of this study is to identify and differentiate normal brain tissue from glioblastoma tissue using optical coherence tomography (OCT) and OCT angiography (OCTA). These techniques offer a non-invasive way to analyze the morphological and microvascular alternations associated with glioblastoma in an animal model. To monitor the changes in morphology and vascular distribution of brain tissue as glioblastoma tumors grow, time-series OCT and OCTA results were collected for comparison. Texture analysis of OCT images was proposed using the gray-level co-occurrence matrix (GLCM), from which homogeneity and variance were calculated as discriminative parameters. Additionally, OCTA was used to assess microvascular characteristics, including vessel diameter, density, and fractal dimension. The findings demonstrate that the proposed methods can effectively distinguish between normal and cancerous brain tissue in vivo.

Investigating the İmpact of Bariatric Surgery on Macular and Peripapillary Vessel Density in Obese İndividuals Without Metabolic Disease.

It is well-established that microvascular structures are affected in obese people with metabolic disease. We aimed to evaluate the effect on microvascular structures by examining macular and peripapillary vessel density with optical coherence tomography angiography (OCTA) after bariatric surgery in obese individuals without metabolic disease. This prospective study included 96 eyes of 48 obese patients. Body mass index (BMI), macular vessel density in the superficial, intermediate, and deep capillary plexus, and peripapillary vessel density were measured before and 6 months after bariatric surgery. BMI decreased significantly to 43.75±4.4 kg/m2 postoperatively compared to 55.31±5.1 kg/m2 preoperatively (p&lt;0.05). A significant increase was observed in macular vessel density in the deep capillary plexus postoperatively (p&lt;0.01). However, no significant postoperative increase occurred in macular vascular density in the superficial and intermediate capillary plexus (p &gt;0.05). Moreover, there was no change in peripapillary vascular density (p&gt;0.05). Postoperative thickening of the foveal, parafoveal, and perifoveal retinal layers was significant (p &lt; 0.001). No significant correlation was detected between BMI change and macular and peripapillary vessel density changes (p&gt;0.05). An increase in macular vascular density, particularly in the deep capillary plexus, and retinal layer thickness has been observed following bariatric surgery performed on obese individuals without metabolic disease. This increase may indicate that microvascular structures are affected even in the absence of metabolic disease and that microperfusion improves with surgery.

Benign Lobular Inner Nuclear Layer Proliferation associated with Congenital Hypertrophy of the Retinal Pigment Epithelium

Purpose: To report two cases of benign intraretinal tumors of the inner nuclear layer (INL) associated with congenital hypertrophy of the retinal pigment epithelium (CHRPE). Methods: Multimodal imaging of two cases, including fundus color and autofluorescence photography, structural and en face spectral-domain optical coherence tomography (SD-OCT), OCT-angiography, fluorescein and indocyanine green angiography. Results: During a routine examination, intraretinal tumors of the INL associated with several CHRPE lesions were observed in one eye of two male patients, aged 27 and 32 years, respectively. Multimodal imaging showed white multifocal lobulated lesions with arching extensions, located in the INL, which allowed diagnosing benign lobular inner nuclear layer proliferation (BLIP). Conclusion: BLIP is a rare benign tumor located in the INL with a unique pattern and only 4 cases have been reported to date. The present two cases allowed confirming that BLIP is associated with CHRPE, suggesting a concomitant developmental anomaly of the RPE and the inner retina.

Analysis of retinal and choroidal microvascular changes using optical coherence tomography and optical coherence tomography angiography in patients with acute leukemia.

Although leukemic retinopathy accounts for 80% of ocular complications in acute leukemia, its pathogenesis remains unclear. To evaluate changes in retinal and choroicapillaris and structural parameters in patients with acute leukemia, we analyzed the correlation between vascular perfusion metrics and laboratory parameters and assessed the changes after hematopoietic stem cell transplantation (HSCT). Herein, 104 eyes of 52 patients aged 18 and above with acute leukemia were enrolled. 80 eyes of 40 healthy patients were recruited as control participants. All participants underwent optical coherence tomography (OCT) and OCT angiography (OCTA) at baseline. Patients with acute leukemia had a significantly thicker ganglion cell-inner plexiform layer (GCIPL) and lower circularity index than the control participants. Post-HSCT perfusion metrics did not differ significantly, but parafoveal thickness decreased significantly. During the active phase of acute leukemia, lower platelet levels were associated with significant GCIPL thickening and increased foveal avascular zone and perimeter. D-dimer levels positively correlated with GCIPL thickness. Patients with acute leukemia had subclinical retinal microvascular deficits on OCTA and GCIPL thickening on OCT, possibly associated with bone marrow function. GCIPL thickness may indicate acute ischemia in such patients. Further studies must elucidate their clinical and prognostic significance.

Retinal Ischemic Perivascular Lesion Reflects Cerebral Small Vessel Disease Burden in Single Subcortical Infarction.

Retinal ischemic perivascular lesions (RIPLs) are an indicator of ischemia in the middle retina. We aimed to determine the relationship between RIPLs and single subcortical infarction (SSI). We also investigated the differences in cerebral small vessel disease imaging burden between groups with and without RIPLs in SSI. In this case-control study, we enrolled 82 patients with SSI and 72 nonstroke controls. All participants underwent magnetic resonance imaging and swept-source optical coherence tomography/optical coherence tomography angiography. Small vessel disease markers such as lacunes, cerebral microbleeds, white matter hyperintensity, and perivascular spaces were rated on brain imaging. RIPLs were assessed via swept-source optical coherence tomography. Optical coherence tomography angiography was used to measure the superficial vascular complex and deep vascular complex of the retina. After adjusting for risk factors, the presence of RIPLs was significantly associated with SSI (odds ratio [OR], 1.506 [95% CI, 1.365-1.662], P<0.001). Eyes with RIPLs showed lower deep vascular complex density (P=0.035) compared with eyes without RIPLs in patients with SSI. After adjusting for vascular risk factors, the presence of RIPLs in patients with SSI was associated with an increased periventricular white matter hyperintensity burden (β=0.414 [95% CI, 0.181-0.647], P<0.001) and perivascular spaces-basal ganglia (β=0.296 [95% CI, 0.079-0.512], P=0.008). RIPLs are associated with SSI independent of underlying risk factors. The relationship between the presence of RIPLs and small vessel disease markers provides evidence that RIPLs might be an additional indicator of cerebral ischemic changes.

Observation of structural and vascular features of retina and choroid in myopia using ultra-widefield SS-OCTA

BackgroundTo find the relationship between the changes of retinal and choriodal structure/ vascular densities (VD) and the myopia progress.Methods126 eyes of 126 age-matched young participants were divided into three groups: Emmetropia and Low Myopia (EaLM) (33 eyes), Moderate Myopia (MM) (39 eyes), and High Myopia (HM) (54 eyes). Fundus images measuring 12 × 12 mm were captured using ultra-widefield swept-source optical coherence tomography angiography (SS-OCTA). Each image was uniformly divided into nine regions: supra-temporal (ST), temporal (T), infra-temporal (IT), superior (S), central macular area (C), inferior (I), supra-nasal (SN), nasal (N), and infra-nasal (IN). Various structural parameters, including inner retina thickness (IRT), outer retina thickness (ORT), and choroid thickness (CT), were assessed, and the VD of the superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaries (CC), and choroid vessels (ChdV) were quantified.ResultsCT in upper fundus exhibited a significant reduction from EaLM to MM. Additionally, ORT (ST, S. SN, C, N, IT, I, IN), CT (ST, S, SN, T, C, N, IT, I, IN) and VDs of SCP (ST, S, C, I, IN), DCP (ST, S, T, C, I) and ChdV (T, N, I, IN) were statistically diminished in EaLM compared to HM. Furthermore, IRT (N), ORT (N, IN), CT (S, SN, T, C, IT, I) and VDs of SCP (I, IN) and DCP (I) exhibited significant decreases as MM progressed towards HM. Intriguingly, there was a notable increase in the VD of CC (ST, S, T, C, N) as myopia progressed from MM to HM.ConclusionSignificant changes in retinal and choroid structure and vascular density occur as moderate myopia advances to high myopia. Efforts to curb myopia progression to this stage are essential, as the failure to do so may lead to the development of corresponding retinopathy.

Microvascular changes using OCT Angiography in diabetic eyes without clinical evidence of retinopathy

Microvascular changes using OCT Angiography in diabetic eyes without clinical evidence of retinopathy