Optical Coherence Tomography Angiography Research Articles

Optical coherence tomography enables longitudinal evaluation of cell graft-directed remodeling in stroke lesions.

Stem cell grafting can promote glial repair of adult stroke injuries during the subacute wound healing phase, but graft survival and glial repair outcomes are perturbed by lesion severity and mode of injury. To better understand how stroke lesion environments alter the functions of cell grafts, we employed optical coherence tomography (OCT) to longitudinally image mouse cortical photothrombotic ischemic strokes treated with allogeneic neural progenitor cell (NPC) grafts. OCT angiography, signal intensity, and signal decay resulting from optical scattering were assessed at multiple timepoints across two weeks in mice receiving an NPC graft or an injection of saline at two days after stroke. OCT scattering information revealed pronounced axial lesion contraction that naturally occurred throughout the subacute wound healing phase that was not modified by either NPC or saline treatment. By analyzing OCT signal intensity along the coronal plane, we observed dramatic contraction of the cortex away from the imaging window in the first week after stroke which impaired conventional OCT angiography but which enabled the detection of NPC graft-induced glial repair. There was moderate, but variable, NPC graft survival at photothrombotic strokes at two weeks which was inversely correlated with acute stroke lesion sizes as measured by OCT prior to treatment, suggesting a prognostic role for OCT imaging and reinforcing the dominant effect of lesion size and severity on graft outcome. Overall, our findings demonstrate the utility of OCT imaging for both tracking and predicting natural and treatment-directed changes in ischemic stroke lesion cores.

Alterations in optical coherence tomography angiography parameters after cataract surgery in patients with diabetes

This prospective study aimed to investigate microvascular changes in diabetic patients undergoing cataract surgery. Foveal avascular zone (FAZ) area, as well as vessel density (VD) in the macula and radial peripapillary capillary plexus (RPC), were compared before and after surgery. Sixty eyes (72.3%) had no diabetic retinopathy (no DR group) and 23 eyes (27.7%) had non-proliferative diabetic retinopathy (DR group). In the no DR group, the FAZ area in the superficial capillary plexus (SCP) decreased from 0.41 ± 0.13 to 0.38 ± 0.11 mm2 (P = 0.036), while no significant change was observed in the DR group (0.33 ± 0.12 to 0.30 ± 0.12 mm2, P = 0.091) at 6 months postoperatively. VD in the RPC increased from 34.4 ± 2.3% to 35.6 ± 2.3% in the no DR group (P = 0.009), but there was no significant change in the DR group (33.0 ± 3.5% vs. 34.0 ± 2.3%, P = 0.051) after 6 months. VD in the macula did not change in either group. Phacoemulsification reduced the FAZ area in the SCP and increased the VD in the RPC in diabetic patients without diabetic retinopathy at six months postoperatively.

Factors Associated with Retinal Microvasculature Dropout Induced by Elevation of Intraocular Pressure in Primary Open-Angle Glaucoma.

To investigate the risk factors related to decrease in vessel density (VD) observed in primary open-angle glaucoma (POAG), due to acute increase in intraocular pressure (IOP) by an ophthalmodynamometer (OPD). This cross-sectional study involved 42 eyes of participants (22 Controls and 20 POAG patients) that underwent optical coherence tomography angiography (OCT-A) to assess VD in the peripapillary region in three examination sets: primary gaze position (1), 25-degree adduction (2) and 25-degree adduction with OPD compression (3). Individual relationships between IOP levels and changes in the superficial complex VD were evaluated after image processing and exclusion of large retinal vessels. Multivariable regression analysis was used to verify factors associated with differences in VD induced by IOP elevation. A significant increase in IOP was induced by OPD compression during adduction (mean ± SD, Control: + 13.8 ± 2.8; POAG: + 13.4 ± 2.1mmHg). Only during IOP elevation (set 3), a significant VD decrease was observed both in POAG eyes (p = 0.008) and controls (p = 0.022). Baseline IOP (p = 0.022), maximum IOP (p = 0.003), and scleral rigidity (p = 0.029) were significantly associated with VD decreases in eyes with POAG. No changes were observed in VD during adduction gaze exclusively. Acute IOP elevation induced with OPD, but not adduction gaze, decreased peripapillary VD measured with OCT-A imaging. IOP levels and scleral rigidity significantly affected VD reduction in POAG patients. Thus, high scleral rigidity may decrease the ability of the globe to dampen the well-known effects of IOP fluctuation on glaucoma onset and progression. What is known Decrease vascular density in the peripapillary retina was associated with POAG, but factors related to the vascular response to elevated IOP are unexplored. What is new OCT-A quantification shows decreases in vascular density of the superficial layers of the peripapillary retina during an acute elevation in IOP. High IOP levels and scleral rigidity significantly affected vascular density reduction in POAG patients.

Artificial intelligence in assessing cardiovascular diseases and risk factors via retinal fundus images: A review of the last decade

AbstractCardiovascular diseases (CVDs) are the leading cause of death globally. The use of artificial intelligence (AI) methods—in particular, deep learning (DL)—has been on the rise lately for the analysis of different CVD‐related topics. The use of fundus images and optical coherence tomography angiography (OCTA) in the diagnosis of retinal diseases has also been extensively studied. To better understand heart function and anticipate changes based on microvascular characteristics and function, researchers are currently exploring the integration of AI with noninvasive retinal scanning. There is great potential to reduce the number of cardiovascular events and the financial strain on healthcare systems by utilizing AI‐assisted early detection and prediction of cardiovascular diseases on a large scale. A comprehensive search was conducted across various databases, including PubMed, Medline, Google Scholar, Scopus, Web of Sciences, IEEE Xplore, and ACM Digital Library, using specific keywords related to cardiovascular diseases and AI. The study included 87 English‐language publications selected for relevance, and additional references were considered. This article provides an overview of the recent developments and difficulties in using AI and retinal imaging to diagnose cardiovascular diseases. It provides insights for further exploration in this field. Researchers are trying to develop precise disease prognosis patterns in response to the aging population and the growing global burden of CVD. AI and DL are revolutionizing healthcare by potentially diagnosing multiple CVDs from a single retinal image. However, swifter adoption of these technologies in healthcare systems is required.This article is categorized under: Application Areas > Health Care Technologies > Artificial Intelligence

Acupuncture as Adjuvant Therapy for Glaucoma: Protocol for a Randomized Controlled Trial.

Glaucoma is a chronic progressive optic neuropathy that necessitates lifelong treatment to reduce the decline of the optic nerve. Due to the extended and continuous treatments required for patients, complementary therapies are often considered alongside conventional treatments to enhance the effectiveness of the treatment. Acupuncture has demonstrated the potential to lower intraocular pressure in previous clinical trials, making it a promising glaucoma intervention. The primary objective of this study is to conduct a single-center randomized control trial involving patients with glaucoma. Acupuncture will be evaluated as an adjunctive therapy. The trial aims to explore its effectiveness for glaucoma. In this single-center randomized controlled trial, participants (N=50) with primary open-angle glaucoma will be randomly assigned to the treatment group, receiving ophthalmic acupuncture with "De Qi" sensation, or the control group, receiving minimum acupuncture stimulation on nonophthalmic acupoints. The intervention will consist of weekly acupuncture treatments for a total of 6 sessions. Participants will be assessed at 8 time points, which are baseline, during the intervention (6 times), and at a 3-month follow-up. The primary outcome measure is a change in the intraocular pressure before and after each acupuncture treatment. Secondary outcomes will include measurements of heart rate and blood pressure before and after acupuncture, best-corrected visual acuity, visual field, optical coherence tomography, optical coherence tomography angiography, the Glaucoma Symptom Scale, and the Glaucoma Quality of Life-15 questionnaire. Recruitment of participants for the trial commenced on June 28, 2023. A total of 10 participants have been enrolled to test the feasibility of the experiment. We anticipate that the preliminary data from this trial will be completed by December 2025. This trial uses rigorous methodology and comprehensive outcome measurements to assess the clinical efficacy of acupuncture as an adjunctive therapy for glaucoma, providing valuable insights for future clinical treatment guidelines. ClinicalTrials.gov NCT05753137; https://clinicaltrials.gov/study/NCT05753137. DERR1-10.2196/57888.

Evaluation of the early effects of the first-dose administration of the Sinovac vaccine on the retina, choroid, and optic disc using optical coherence tomography (OCT) and OCT-angiography

Aim To determine the effects of the first-dose administration of the Sinovac vaccine on the retina, choroid, and optic disc in healthy participants. Methods This prospective design study was conducted with 27 healthy healthcare workers who received the first dose of Sinovac vaccine and 25 healthy controls who were not vaccinated. In the vaccinated group, ophthalmological examinations and measurements were performed before vaccination and one week and one month after vaccination. Subfoveal, nasal, and temporal choroidal thicknesses (CTs), retinal nerve fiber layer (RNFL) thickness, and macular thickness (MT) were determined using spectral domain-optical coherence tomography at all visits. Superficial, deep, and peripapillary radial capillary plexus (superficial capillary plexus, deep capillary plexus (DCP), and radial peripapillary capillary, respectively), choriocapillaris vascular density, and foveal avascular zone parameters were measured on optical coherence tomography-angiography (OCT-A). Results No significant difference was detected between the two groups in terms of the parameters measured by OCT and OCT-A (p > 0.05 for all). The CT values measured in all quadrants were significantly higher at the first week after vaccination (p < 0.05 for all), and they returned to their pre-vaccination values at the first month post-vaccination measurement (p > 0.05 for all). Concerning the RNFL and MT values, there was no significant difference between the pre-vaccination and post-vaccination first-week measurements (p > 0.05 for all), but a statistically significant increase was detected in the post-vaccination first-month MT and RNFL measurements (p < 0.05 for all). Only the decreases in the foveal DCP and choriocapillaris vascular density values were significant at the first week after vaccination (p < 0.05 for all). Conclusion The early changes detected after vaccination in this study suggest the possibility that autoimmune, vascular, and inflammatory diseases may simultaneously emerge in the early post-vaccination period or may be triggered after vaccination, or that the vaccine may unmask these diseases.

Optical Coherence Tomography Image Analysis for Detection of Alzheimer’s Disease: A Comprehensive Structured Review

Optical Coherence Tomography (OCT) has emerged as a promising non-invasive imaging modality for the early detection of Alzheimer’s Disease (AD). This systematic literature review aims to consolidate current research on OCT image analysis for AD detection, addressing the growing need for early and accurate diagnostic tools. Despite the advances in neuroimaging, early diagnosis of AD remains challenging due to its asymptomatic nature in initial stages and the invasiveness of traditional methods. To achieve this, we conducted an extensive search of related articles from reputable databases (Scopus and Web of Science), focusing on studies published between 2022-2024. The flow of study was based on PRISMA framework. The database found (n = 29) final primary data. This review was divided into three themes, (1) retinal and ocular biomarkers for AD, (2) optical coherence tomography angiography (OCTA) and imaging techniques, and (3) machine learning and computational approaches for Alzheimer’s disease diagnosis. Key findings include the enlargement of the periarteriole capillary-free zone and changes in retinal nerve fibre layer thickness as potential AD biomarkers. Based on the review, the implementation of image analysis for OCT images have shown substantial potential for AD detection. By evaluating the past studies, gaps for the current research were discovered including the need for larger, more diverse cohorts and longitudinal studies to validate these biomarkers. In summary, detection of AD is possible through thorough OCT image analysis, but further research could be suggested to enhance its clinical applicability and reliability.

Paediatric staphyloma classification: new perspectives via ultrawide field three-dimensional swept-source optical coherence tomographic angiography

AimTo employ ultrawide field three-dimensional swept-source optical coherence tomographic angiography (UWF 3D SS-OCTA) modality, integrating novel strategies, posterior eye curvature maps and posterior eye height maps, in characterising the features...

Role of Plasma Angiopoietin-1 and VEGF Levels as Potential Biomarkers in Chronic Central Serous Chorioretinopathy with Macular Neovascularization.

To evaluate the plasma levels of angiopoietin-1 and vascular endothelial growth factor (VEGF) and their association with macular neovascularization (MNV) in patients with chronic central serous chorioretinopathy (cCSC). Correlations between plasma cytokine levels, CSC duration, and mean choroidal thickness (CT) were also investigated. Of the 59 patients with cCSC, 10 patients with MNV secondary to cCSC and 10 patients with cCSC without MNV were enrolled in the study. The control group included 15 healthy volunteers matched for age, sex, smoking status, and comorbidities. Chronic CSC was diagnosed based on typical findings on swept-source optical coherence tomography (OCT), fundus fluorescein angiography, and indocyanine green angiography. Additionally, all patients underwent OCT angiography to help detect MNV. Plasma angiopoietin-1 and VEGF levels were assessed using multiplex immunoassay. The plasma angiopoietin-1 levels differed between the 3 groups (p = 0.005). The angiopoietin-1 levels were lower in patients with cCSC with MNV than in controls (p = 0.006). There were no differences in the plasma VEGF levels between all the 3 groups (p = 0.329). The VEGF levels were negatively correlated with mean CT in cCSC patients with MNV (rho = -0.683, p = 0.042) but correlated positively with disease duration in patients with cCSC without MNV (rho = 0.886, p = 0.003). Our study confirms that MNV is a common complication of cCSC and provides new insights into the role of angiopoietin-1 in cCSC and MNV. Reduced angiopoietin-1 levels in cCSC patients, regardless of MNV status, highlight the importance of the Ang-Tie2 pathway in disease pathogenesis and may point to new therapeutic targets and future novel treatments to improve the management of these patients.

CORRIGENDUM: Optical coherence tomography angiography features in Waldenström macroglobulinemia patients without Hyperviscosity syndrome: A pilot prospective study

PurposeTo evaluate the retinal vessel density (VD) with optical coherence tomography angiography (OCTA) in asymptomatic patients affected by Waldenström macroglobulinemia (WM) without hyperviscosity syndrome (HVS) and to highlight the presence of microvascular damage in theese clinically asymptomatic WD patients. DesignProspective study. MethodsA total of 43 eyes from 43 WM patients (24 females, 19 males, mean age 55.1 ± 13.6 years) were enrolled from January 2023 to December 2023 in the Eye Clinic of the University of Naples Federico II. .Along with WM patients, 40 healthy subjects (HS) (20 females, 20 males, mean age 52.3 ± 15.6 years) with a normal ophthalmic examination and no history of intraocular surgery or retinal pathologic features were included as control group All patients and controls underwent OCTA. ResultsThe two groups were not significantly different for age and sex Visual acuity examination showed no statistically significant difference in BCVA between controls and patients Compared to HS, WD patients showed lower VD values in the SCP in the whole image (47.95 ± 5.17 % vs. 52.99 ± 2.52%; p < 0.001), as well as in the parafovea (53.01 ± 6.69 % vs. 55.30 ± 2.61%; p = 0.002), and fovea (21.38 ± 9.01 % vs. 30.31 ± 5.84 %; p < 0.001). On the other hand, in the DCP VD values were significantly higher in patients compared to controls in the whole image (55.82 ± 8.07 % vs. 50.83 ± 5.46%; p = 0.005), as well as in the parafovea (56.76 ± 6.26 % vs. 52.59 ± 5.46%; p = 0.001), and fovea (38.75 ± 8.59 % vs. 33.43 ± 8.68 %; p < 0.001). ConclusionThe finding that OCTA confirmed the presence of widespread microvascular damage in WD patients clinically silent. Thus, OCTA is a safe rapid imaging technique that could represent a valid biomarker of systemic vascular dysfunction.

Optical Coherence Tomography and Optical Coherence Tomography Angiography in Optic Nerve Disorders

Optic nerve disorders encompass a wide range of diseases. While it may be an isolated disease, such as optic disc drusen, it may also occur as a symptom of pathology in the central nervous system, such as multiple sclerosis. Optical coherence tomography (OCT) is an important auxiliary test used in optic nerve disorders as it allows cross-sectional imaging of the retina and optic nerve head at high resolution. OCT is used in the diagnosis of optic nerve disorders, evaluation of response to treatment, and prediction of visual prognosis by measuring retinal layers such as the ganglion cell layer (GCL) and retinal nerve fiber layer (RNFL).

Changes in choroidal thickness and blood flow in response to form deprivation-induced myopia and repeated low-level red-light therapy in Guinea pigs.

To evaluate ocular refractive development, choroidal thickness (ChT) and changes in choroidal blood flow in form-deprived myopia (FDM) Guinea pigs treated with repeated low-level red-light (RLRL) therapy. Twenty-eight 3-week-old male tricolour Guinea pigs were randomised into three groups: normal controls (NC, n = 10), form-deprived (FD, n = 10) and red light treated with form-deprivation (RLFD, n = 8). Interocular refraction and axial length (AL) changes were monitored. Optical coherence tomography angiography (OCTA) measured choroidal thickness, vessel area density, vessel skeleton density and blood flow signal intensity (flux) in the choriocapillaris and medium-large vessel layers. The experimental intervention lasted 3 weeks. At week 3, the FD group had higher myopia and longer axial length than the NC group (all p < 0.001). The RLFD group had higher hyperopia and shorter axial length than the FD group (all p < 0.001). At week 1, the NC group had a thicker choroidal thickness than the FD group (p < 0.05). At weeks 2 and 3, the RLFD group had a thicker choroidal thickness than the FD group (p = 0.002, p < 0.001, respectively). Additionally, the NC group had higher vessel area density, vessel skeleton density and flux in the choriocapillaris layer than the FD group at the three follow-up time points (all p < 0.05). At week 3, the vessel skeleton density and flux were higher in the RLFD group than in the FD group (all p < 0.05). Correlation analysis results showed that weekly changes in refraction and choroidal thickness were negatively correlated with changes in axial length (all p < 0.05). Choroidal thickness changes were positively correlated with alterations in the vessel area density, vessel skeleton density and flux in the choriocapillaris layer, as well as vessel skeleton density and flux changes in the medium-large vessel layers (all p < 0.05). Repeated low-level red-light (RLRL) therapy retards FDM progression in Guinea pigs, potentially through increased choroidal blood flow in the choriocapillaris layer.

IMPACTS OF POSTERIOR STAPHYLOMA ON PARAPAPILLARY MICROVASCULATURE AND ATROPHY IN HIGH MYOPIC EYES: A MATCHED COHORT STUDY WITH OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

We aimed to evaluate the impacts of the different types of posterior staphyloma (PS) in high myopia on parapapillary microvasculature and parapapillary atrophy (PPA, i.e., γ-zone and δ-zone) with optical coherence tomography angiography. This cross-sectional study included 152 high myopic eyes (152 participants) with γ-zone. After matching, high myopic eyes were stratified into PS (n = 33) and non-PS (n = 33) groups. PS types, parapapillary microvasculature characteristics, the prevalence of non-juxtapapillary microvasculature dropout (NJ-MvD), the longest radial width from the optic disc edge to retinal pigment epithelium atrophy edge (PPA-w), γ-zone, and δ-zone with changes in visual field and best-corrected visual acuity (BCVA) were evaluated and analyzed. According to Curtin's classification, we identified five types of PS included: primary types I, II, III, and compound types VII, and IX. Eyes with type II showed a higher optic disc tilted ratio and larger PPA-w compared to other primary PS. Subjects with type IX were the oldest. Eyes with types VII and IX had wider γ-zone and δ-zone, worse visual field outcomes, poorer BCVA, and a higher incidence of NJ-MvD compared to primary PS. Choroidal and intrascleral vessels were associated with NJ-MvD and were located near or connected to the circle of Zinn-Haller. Eyes with high myopia and PS show wider PPA, affecting the γ-zone and δ-zone, and are at a higher risk of developing NJ-MvD. Specifically, eyes with PS types VII and IX are more susceptible to visual field damage and decreased BCVA. These results highlight the importance of impact of PS on PPM and PPA in high myopia.

Baseline Features in Polypoidal Choroidal Vasculopathy in Caucasian Patients

Introduction: The aim of this study was to investigate demographic, anatomical, angiographic, and functional parameters in patients suffering from polypoidal choroidal vasculopathy (PCV). Methods: Sixty eyes of 60 patients with a definite diagnosis of treatment-naïve exudative unilateral PCV were evaluated in this retrospective study. Fellow eyes and age-matched healthy subjects were enrolled as comparison. All subjects underwent complete ophthalmic evaluation with multimodal imaging assessment, including spectral-domain optical coherence tomography (OCT) and OCT angiography. Main outcome measures in the comparison analysis were central macular thickness (CMT), subfoveal choroidal thickness (SFCT), and choroidal vascularity index (CVI), whereas outcome measures for correlation analyses were best corrected visual acuity (BCVA), intraretinal fluid and subretinal fluid (SRF) presence, SRF thickness, vascularized pigmented epithelial detachment height, and PCV outer retina to choriocapillaris flow area. Results: CVI was significantly higher in affected and fellow eyes if compared with the healthy ones (p = 0.049; p = 0.003). Subfoveal choroid resulted to be thicker in the diseased eyes when compared with healthy ones (p = 0.002). A negative correlation was assessed between age and SFCT, CMT, and BCVA. In addition, a significant association between male gender and anatomical and functional parameters has been found with male prevalence at baseline in cases. No association between systemic conditions and PCV features was found. Conclusions: Patients with unilateral PCV show choroidal changes in terms of higher values of CVI, also in fellow eyes, that were negatively related with age. In our cohort of patients, males showed the poorest diagnosis with a baseline lower BCVA and higher CMT when compared with females. PCV was not associated with any systemic condition.

Optical coherence tomography (OCT) and OCT Angiography in Stages 3 and 4 proliferative sickle cell retinopathy

PurposeTo investigate macular findings in Goldberg stages 3 and 4 proliferative sickle cell retinopathy (PSCR) using optical coherence tomography (OCT) and OCT Angiography MethodsA case-control study using retrospective OCT and OCTA data from PSCR eyes (cases) and prospective data from age and sex-matched normal (controls). OCTA data included vessel density (VD) in the superficial capillary vascular plexus (SCP) and deep capillary vascular plexus (DCP), foveal avascular zone (FAZ) characterization, including the shape (in the SCP & DCP), size (area covered), and perimeter. OCT data were whole, superior, and inferior hemi-retina thickness for the superficial and deep retina. ResultsThere were 38 OCT / OCTA scans of PSCR eyes of 21 SCD patients; ten eyes were excluded for not meeting inclusion criteria. We analyzed nineteen (19) patients (ten unilateral and 9 bilateral), 28 eyes, nine SS eyes (32%), and nineteen SC eyes (68%). The controls consisted of 29 eyes of 16 normal subjects (three unilateral and 13 bilateral). The commonest FAZ shape in PSCR was “irregular” in 14 eyes (50%), followed by “round” in 11 eyes (39.3%) versus controls, the commonest shape “round” in 18 eyes (62%), followed by “irregular” 9 eyes (31%) (p = 0.165). FAZ area and perimeter were larger in PSCR (p > 0.05). The deep and superficial VD was reduced in PSCR. The mean whole deep VD for cases was 48.9 ± 6.1 versus 52.9 ± 6.4 for controls (p = 0.019). Mean whole superficial VD for cases was 47.4 ± 5.5 versus 49.8 ± 3.4 for controls (p = 0.058).Retina thickness in the whole, superior and inferior hemi-retina, for superficial and deep retina, was higher in PSCR compared to controls (p < 0.05). Superficial whole thickness for cases and controls were 287.0 µm [IQR 35.3 µm] versus 273.0 µm [IQR 18 µm] respectively (p = 0.008). Deep whole thickness for cases and controls was 287.0 µm [IQR 35.25 µm] versus 273.0 µm [IQR 18 µm] (p = 0.008).VD was reduced in SS compared to SC eyes (deep whole VD: 50.28 ± 6.01 vs 46.78 ± 5.80) (p = 0.139). Retina thickness in SS was reduced relative to SC. Peripheral retinal laser photocoagulation did not affect VD, though it was associated with a thinner macula. ConclusionOCT/OCTA of stage 3 and 4 PSCR revealed reduced VD in the DCP and SCP. Despite the thin temporal retina in SCD, there is a thicker whole, superior, and inferior hemiretina in both the superficial and deep retina. An irregularly shaped FAZ is common, a reflection of abnormal microcapillary loss in the perifoveal area.

Retinal morphology and microvasculature density alterations in generalized anxiety disorders

Purpose This study evaluates morphological alterations in the macula and peripapillary regions of patients with Generalized Anxiety Disorder (GAD) using optical coherence tomography (OCT) and OCT angiography (OCT-A). We compared these changes with healthy controls to determine GAD’s impact on the retina. Methods An observational case-control study was conducted from January to May 2024 at the Benghazi Teaching Eye Hospital, including 40 GAD patients and 40 healthy controls aged 30–65 years. Participants underwent comprehensive ophthalmic assessments, including OCT and OCT-A. We analyzed retinal parameters such as central macular thickness (CMT), Macular volume, Ganglion cell layer thickness, and retinal nerve fiber layer (RNFL) thickness, along with vessel density in the macular and peripapillary regions. Results GAD patients exhibited significantly lower CMT (243.30±21.15 μm vs. 268.79±17.34 μm, P=0.001), Macular volume (9.48±0.62 mm3 vs. 10.17±0.39 mm3, P=0.001), Ganglion cell layer thickness (83.60±78.24 μm vs. 92.30±74.73 μm, P=0.001), and total RNFL thickness (93.90±11.05 μm vs. 97.76±8.67 μm, P=0.001) compared with controls. RNFL thinning was noted in the nasal, inferior, and temporal regions. However, OCT-A revealed no significant differences in vessel density in the peripapillary and central macular areas between GAD patients and controls. Conclusion Patients with GAD exhibit significant retinal structural changes, particularly in the macular and RNFL regions. However, no significant differences in retinal vessel density were observed. These findings suggest that GAD may impact retinal morphology but not vascular density, indicating potential biomarkers for early detection and monitoring of GAD-related neurodegeneration.

Detection of macular neovascularization in eyes presenting with macular edema using optical coherence tomography angiography and a deep-learning model

PurposeTo test the diagnostic performance of an artificial intelligence algorithm for detecting and segmenting macular neovascularization (MNV) with optical coherence tomography (OCT) and OCT angiography(OCTA) in eyes with macular edema from various diagnoses. DesignProspective cross-sectional study. ParticipantsStudy participants with macular edema due to either treatment-naïve exudative age-related macular degeneration (AMD), diabetic macular edema (DME), or retinal vein occlusion (RVO). MethodsStudy participants were imaged with macular 3x3-mm and 6x6-mm spectral-domain OCTA. Eyes with exudative AMD were required to have MNV in the central 3x3-mm area. A previously developed hybrid multi-task convolutional neural network for MNV detection (aiMNV) and segmentation was applied to all images, regardless of image quality. Main Outcome MeasuresSensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of detecting MNV; and intersection over union(IoU) score and F1 score for segmentation. ResultsOf 114 eyes from 112 study participants, 56 eyes had MNV due to exudative AMD and 58 eyes with macular edema due to either DME or RVO. 3x3-mm OCTA scans with aiMNV detected MNV with 96.4% sensitivity, 98.3% specificity, 98.2% PPV, and 96.6% NPV. For segmentation, the average IoU score was 0.947 and the F1 score was 0.973. 6x6-mm scans performed well; however, sensitivity for MNV detection was lower than 3x3-mm scans due to lower scan sampling density. ConclusionThis novel aiMNV algorithm can accurately detect and segment MNV in eyes with exudative AMD from a control group of eyes that present with macular edema from either DME or RVO. Higher scan sampling density improved the aiMNV sensitivity for MNV detection.

Evaluation of macular and optic nerve head changes by optical coherence tomography angiography in glaucomatous eyes

Background Optical coherence tomography angiography (OCTA) is introduced as a safe, noninvasive, and dye-free technology that provides an assessment of both large vessels and microvasculature of the retina and some parts of the choriocapillaris. Measuring vessel densities using OCTA at both the macula and optic nerve head (ONH) in glaucomatous eyes and comparing them with those of normal eyes will give us an idea about the effect of glaucoma on vessel densities and the role of OCTA in controlling and monitoring glaucoma progression, which remains despite the various medical and surgical treatment options, the second most common reason of blindness worldwide. Aims The current study aimed to assess vessel densities in glaucomatous patients at both the macula and ONH and compare them with vessel densities of normal participants and to assess if OCTA can be useful in the diagnosis and monitoring of the disease. Settings and design Case–control study. Patients and methods The study enrolled 60 patients who were divided into two groups. Group 1 included 30 patients with any type of glaucoma and group 2 included 30 normal participants. OCTA was performed on all of them to assess the macular and ONH vessel densities. Results Glaucomatous patients showed decreased vessel density at the macula and the ONH. The vessel densities at the foveal and all quadrants of parafoveal regions of the macula were decreased when compared with vessel densities of normal participants. Vessel densities at all quadrants of the peripapillary region also decreased when compared with those of normal participants with a strong positive correlation between average peripapillary vessel density and average peripapillary retinal nerve fiber layer thickness. Conclusions Both macular vessel density and ONH vessel density are affected in glaucoma and that may play a role in the diagnosis and follow-up of the disease.

Evaluation of foveal avascular zone changes in patients with type 1 diabetes using optical coherence topography angiography

Aim To evaluate vascular changes in the foveal avascular zone in pediatric patients with type 1 diabetes by using optical coherence tomography angiography (OCTA). Patients and methods This cross-sectional study was performed in Benha University Hospital at Department of Ophthalmology. The patients were obtained from the Pediatric Endocrinology Clinic in Benha University Hospital. The study was conducted on 48 patients (96 eyes) divided into two groups: group A, 24 diabetic children with type 1 diabetes, group B, 24 healthy children of the same age and sex who met the inclusion criteria. The patients were collected from April 2022 to April 2023. The patients were photographed using the Optovue AngioVue OCTA System. Results Our results show that according to the foveal avascular zone it was slightly wider in type 1 diabetic cases with no clinically evident diabetes retinopathy (DR) than control. There were insignificant differences between the two groups as regards foveal density, but as regards foveal thickness, it was significantly lower in diabetic cases than in the control group. Conclusion We discovered that OCTA could consistently identify microvascular changes in the Deep and Superficial Capillary Plexus prior to the clinical indications’ onset of DR. In order to assess the OCTA potential for the screening of DR in children with T1DM, it is necessary to conduct numerous prospective studies.

ACUTE POSTERIOR MULTIFOCAL PLACOID PIGMENT EPITHELIOPATHY AND PLACOID VARIANT DISEASES MASQUERADING AS AGE-RELATED MACULAR DEGENERATION IN THE ELDERLY: A Case Series.

To report eight cases of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) or persistent placoid maculopathy (PPM) initially masquerading as age-related macular degeneration in elderly individuals. APMPPE or PPM eyes in patients above age 55 years with macular retinal pigment epithelium disruption including drusenoid lesions on macular examination and/or with multimodal imaging were included. At least one method of multimodal imaging including fluorescein angiography (FA), indocyanine green angiography, optical coherence tomography (OCT), and OCT angiography (OCTA) was performed in all eyes for diagnosis and to monitor for macular neovascularization. Eight elderly male patients presented with vision loss and were all initially diagnosed with non-neovascular or neovascular age-related macular degeneration. With the aid of multimodal retinal imaging, a final diagnosis of either APMPPE or PPM was rendered. With FA and indocyanine green angiography, choroidal hypoperfusion was detected in all but one eye. With OCT, the angular sign of Henle fiber layer hyperreflectivity was identified in >50% of eyes. With OCTA, inner choroidal flow deficits were detected in all eyes. Macular neovascularization requiring anti-vascular endothelial growth factor injection therapy complicated three of eight cases. Both APMPPE and PPM may develop in elderly individuals and may masquerade as age-related macular degeneration on presentation. Multimodal imaging including FA, indocyanine green angiography, and OCTA are important diagnostic modalities to assess for inner choroidal hypoperfusion to arrive at an accurate diagnosis and to detect macular neovascularization, which frequently complicates APMPPE and PPM. In these patients, serial anti-vascular endothelial growth factor intravitreal injections are essential in treating macular neovascularization and in preventing significant vision loss.