Optical Coherence Tomography Angiography Features Research Articles

Optical coherence tomography angiography features of retinal artery occlusion before and after intra‐arterial thrombolysis

AbstractBackgroundTo evaluate the ability of optical coherence tomography angiography (OCTA) to quantitatively assess the effectiveness of intra‐arterial thrombolysis (IAT) surgery for the treatment of retinal artery occlusion (RAO).MethodsThis was a prospective observational study. Patients diagnosed with RAO who received IAT were enrolled. All participants underwent comprehensive ophthalmologic examinations and OCTA scans. The best‐corrected visual acuity (BCVA), vascular densities (VDs) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), radial peripapillary capillaries, and central retinal thickness (CRT) were recorded. The above parameters were compared between RAO eyes and the fellow healthy eyes before and after IAT. Correlations between the BCVA and OCTA parameters in RAO eyes were calculated.ResultsThirty‐four eyes from 34 consecutive RAO patients with a mean age of 51.0 ± 12.9 years were enrolled. There was a considerable decrease of VDs in the SCP, DCP, and radial peripapillary capillaries in all RAO eyes (all p < 0.001). Compared with contralateral normal eyes, CRT was significantly increased in RAO eyes (p < 0.001). The SCP and DCP VDs were significantly improved after IAT surgery (p = 0.010 and 0.014, respectively). BCVA in logMAR unit was negatively correlated with the DCP VD (r = −0.664, p = 0.010) and positively correlated with CRT (r = 0.597, p = 0.024) after surgery, but not significantly correlated with VDs or CRT before surgery.ConclusionMacular and peripapillary VDs of the retina detected by OCTA were greatly decreased in RAO eyes and improved after IAT treatment. OCTA is capable of quantifying VDs in separate retinal layers non‐invasively, conveniently, efficiently, and precisely.

Optical coherence tomography angiography features in a case of hydroxychloroquine retinopathy.

Optical coherence tomography angiography features in a case of hydroxychloroquine retinopathy.

Biomarkers of macular neovascularisation activity using optical coherence tomography angiography in treated stable neovascular age related macular degeneration

BackgroundThe aim of this study was to describe features of disease activity in patients with treated stable macular neovascularisation (MNV) in neovascular age related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA).MethodsThirty-two eyes of 32 patients with nAMD were included in this prospective, observational study. These patients were undergoing treatment with aflibercept on a treat-and-extend regimen attending an extension to a 12-week treatment interval.ResultsAll subjects had no macular haemorrhage and no structural OCT markers of active MNV activity at the index 12-week treatment extension visit. 31/32 OCTA images were gradeable without significant imaging artefact. The mean MNV size was 3.6mm2 ± 4.6mm2 and 27 (87.1%) had detectable MNV blood flow. 29/31 (93.5%) subjects had MNV with mature phenotypes including 10 non-specific, 10 tangle and 3 deadtree phenotypes. MNV halo and MNV central feeder vessel were noted in 18 (58.1%) and 19 (61.3%) of subjects respectively; only 1 (3.2%) subject was noted to have a MNV capillary fringe.ConclusionsMNV blood flow is still detectable using OCTA in the majority of subjects in this study with treated stable MNV. OCTA features associated included MNV mature phenotype, MNV feeder vessel, MNV halo and absence of capillary fringe.

Visual acuity changes associated with foveal ischemia detected by optical coherence tomography angiography in type II diabetic patients without diabetic retinopathy

Purpose Diabetic macular ischemia is a vision-threatening complication of diabetes mellitus. Early detection of ischemic changes can preserve the vision. The aim of the study was to detect the early macular ischemic changes in patients with no diabetic retinopathy (NDR), using optical coherence tomography angiography, and to correlate these changes with the best-corrected distance visual acuity (BCDVA). Patients and methods A case–control study was conducted to compare 30 diabetic eyes with NDR with 30 healthy control eyes. The glycemic control was determined by glycosylated hemoglobin level less than 6.5%. The diabetic group was further subdivided into those with normal BCDVA and those with decreased BCDVA. The outcome measures included BCDVA and optical coherence tomography angiography features. Results Compared with controls, the diabetics with decreased BCDVA were found to have significantly thinner central macular thickness (P<0.001), larger foveal avascular zone (FAZ) area (P<0.001) in the superficial and deep capillary plexuses (sFAZ and dFAZ), and lower vascular density (VD) (P<0.05) regarding the central density and the superior, inferior, and temporal quadrants. In addition, they showed significantly larger associated capillary dropout areas in the superficial and deep capillary plexuses and significantly lower foveal and parafoveal VD compared with diabetics with normal BCDVA (P<0.001 and 0.05, respectively). Diabetics with normal BCDVA showed no significant difference from the controls regarding the dFAZ and VD but showed significantly lower sFAZ area (P<0.05). Conclusion Diabetic ischemic microvascular changes including decreased VD and enlarged FAZ areas precede clinically visible retinopathy and might be correlated with decreased visual acuity in patients with NDR.

Optical Coherence Tomography Angiography Characteristics of Polypoidal Lesions in Caucasians.

The aim of the study is to analyze the swept source-optical coherence tomography angiography (SS-OCTA) characteristics of polypoidal lesions in Caucasian patients. In this retrospective observational case series, 43 polypoidal lesions in 32 eyes of 32 patients were diagnosed using indocyanine green angiography (ICGA) and compared to SS-OCTA at a tertiary medical retina center (Clinic Landstraße, Vienna Healthcare Group, Austria) between June 2017 and March 2020. Vascularity was identified by color-coded B-scan SS-OCTA while morphology was described as revealed by en face SS-OCTA after alignment with ICGA-confirmed findings. In total, SS-OCTA detected all polypoidal lesions, as identified by ICGA. On B-scan SS-OCTA, circumscribed flow was detected in 33 (76.7%) polypoidal lesions and diffuse flow in 10 (23.3%) lesions. On en face SS-OCTA, polypoidal lesions appeared morphologically as 19 tangled vessel balls (44.2%), 6 tangled vessel balls next to dilated vessels (13.9%), 8 vascular dilatations (18.6%), and 8 ill-defined vascular networks (18.6%), leaving 2 lesions (4.6%) undetected. Circumscribed flow was significantly associated with tangled vessel balls (p = 0.005). This study highlights the importance of a multimodal imaging approach, including SS-OCTA, for the evaluation of polypoidal lesions. Our findings suggest a morphological heterogeneity of vascular patterns in Caucasian patients with polypoidal lesions, as pictured by SS-OCTA.

Prognosis criteria of optical coherence tomography angiography for the long-term efficacy of anti-VEGF therapy of neovascular age-related macular degeneration

The study aimed to determine the most significant optical coherence tomography angiography (OCTA) parameters in terms of predicting anti-VEGF therapy effectiveness during long-term (3-year) follow-up of patients with neovascular age-related macular degeneration (nAMD). The study included 122 patients (122 eyes) with mean age of 73.4±6.6 years who were diagnosed with nAMD. Subgroup analysis included 50 patients (50 eyes) with detailed OCT angiography examination of macular neovascularization (MNV) characteristics and their changes in the course of the follow-up, which lasted 144 weeks. All patients were treated by angiogenesis inhibitor (aflibercept 2 mg), most of them - according to Treat-and-Extend protocol. Treatment response (either 'good' or 'partial') was achieved in all patients, and the proportion of the response types was similar in both types 1 and 2 MNV. Key OCTA parameters associated with the number of injections, as well as morphological and functional response (best-corrected visual acuity, retinal neuroepithelium and pigment epithelium detachment), were vascular network area and MNV area assessed at baseline and three months after treatment initiation. Both of these parameters were closely related in both MNV types during the follow-up. Key parameter with maximum number of clinically significant correlations ('very high' strength, p<0.05) in eyes with 'good' response was MNV area, in eyes with 'partial' response - vascular density and greatest vascular caliber. Vascular network area and MNV area assessed at baseline and after three loading doses were determined as the most significant OCTA characteristics for predicting the number of injections and treatment response based on functional and morphological parameters. MNV area was found to be the most clinically significant marker in 'good' response, vascular density and greatest vascular caliber - in 'partial' response.

Choroidal neovascularization related to melanocytic naevus – a single centre study

Purpose: To assess the angiographic and optical coherence tomography angiography (OCTA) features as well as the natural course of the choroidal neovascularization (CNV) associated with choroidal naevi.&#x0D; Setting/venue: Ocular Oncology Service, Department of Ophthalmology, Poznan University of Medical Sciences.&#x0D; Material and methods: Retrospective chart analysis of the patients who presented to the Ocular Oncology Service in Poznan, Poland between 2011–2021 with the diagnosis of suspicious choroidal naevus. In all patients full ophthalmic examination and multimodal imaging, including fundus photography, autofluorescence, B-ultrasound, optical coherence tomography (OCT), OCT angiography (OCTA) and fluorescein angiography (FAF), were performed.&#x0D; Results: There were 9 lesions in 9 patients, 9 women aged 14–79 years (mean age: 58.2 years). All the lesions were located in the posterior pole and most of them were pigmented (88.9%). CNVs associated with choroidal naevi were type I in 66.7% and type II in 33.3% of cases. 5 patients required treatment: anti-VEGF injection (alone or with transpupillary thermotherapy) was administered. The median follow-up was 24 months (range: 2–145). In two of all treated patients (40%), we observed BCVA gain (2–4 lines), in one patient (20%) it remained stable and in two (40%) it deteriorated. The final visual acuity was below 0.1 only in 1 patient. During the period of observation none of the lesions progressed to uveal melanoma.&#x0D; Conclusions: CNV associated with choroidal naevus could be the reason for subretinal fluid (SRF) leakage and visual loss. The response to anti-VEGF treatment is satisfactory in the majority of patients. Choroidal naevi with accompanying CNV have none or very low malignant transformation potential.

Liver fibrosis and retinal features in an older Mediterranean population: Results from the Salus in Apulia study.

Age is a leading contributor to the liver fibrosis rate and a gradual deterioration of optical function, but this association in older populations is still under-explored. The present study aimed to explore the link between vascular and neural retinal characteristics and the risk of liver fibrosis in 731 older adults from the population-based Salus in Apulia study. Retinal features were obtained using optical coherence tomography (OCT) and OCT-angiography (OCT-A). Liver fibrosis risk was taken as the fibrosis-4 (FIB-4) score. Generalized linear models (logistic regression) were used to estimate the association effect between each unit increase of OCT and OCT-A parameters as independent variables and a FIB-4 ≥ 2.67 score as an outcome. Generalized additive models were used to assess the non-linear association between OCT-A features and the linear FIB-4 score. Increased gangliar cell complex (GCC) thickness was inversely associated with a FIB-4 score above the cut-off in both the raw model (OR: 0.98; 95% CI: 0.96-0.99; SE: 0.01) and after adjustment for age, sex, education, hypertension, diabetes, total cholesterol, and triglycerides (OR: 0.98; 95% CI: 0.97-0.99; SE: 0.01). Our findings add to the growing volume of scientific literature demonstrating that liver fibrosis is associated with retinal neurodegeneration. This study raises a number of new questions, including whether OCT-A may be used to track the progression of metabolic abnormalities and define exact thresholds for predicting and classifying liver disease.

Insights into Sickle Cell Disease through the Retinal Microvasculature: Adaptive Optics Scanning Light Ophthalmoscopy Correlates of Clinical OCT Angiography.

Clinical OCT angiography (OCTA) of the retinal microvasculature offers a quantitative correlate to systemic disease burden and treatment efficacy in sickle cell disease (SCD). The purpose of this study was to use the higher resolution of adaptive optics scanning light ophthalmoscopy (AOSLO) to elucidate OCTA features of parafoveal microvascular compromise identified in SCD patients. Case series of 11 SCD patients and 1 unaffected control. A total of 11 eyes of 11 SCD patients (mean age, 33 years; range, 23-44; 8 female, 3 male) and 1 eye of a 34-year-old unaffected control. Ten sequential 3 × 3 mm parafoveal OCTA full vascular slab scans were obtained per eye using a commercial spectral domain OCT system (Avanti RTVue-XR; Optovue). These were used to identify areas of compromised perfusion near the foveal avascular zone (FAZ), designated as regions of interest (ROIs). Immediately thereafter, AOSLO imaging was performed on these ROIs to examine the cellular details of abnormal perfusion. Each participant was imaged at a single cross-sectional time point. Additionally, 2 of the SCD patients were imaged prospectively 2 months after initial imaging to study compromised capillary segments across time and with treatment. Detection and characterization of parafoveal perfusion abnormalities identified using OCTA and resolved using AOSLO imaging. We found evidence of abnormal blood flow on OCTA and AOSLO imaging among all 11 SCD patients with diverse systemic and ocular histories. Adaptive optics scanning light ophthalmoscopy imaging revealed a spectrum of phenomena, including capillaries with intermittent blood flow, blood cell stasis, and sites of thrombus formation. Adaptive optics scanning light ophthalmoscopy imaging was able to resolve single sickled red blood cells, rouleaux formations, and blood cell-vessel wall interactions. OCT angiography and AOSLO imaging were sensitive enough to document improved retinal perfusion in an SCD patient 2 months after initiation of oral hydroxyurea therapy. Adaptive optics scanning light ophthalmoscopy imaging was able to reveal the cellular details of perfusion abnormalities detected using clinical OCTA. The synergy between these clinical and laboratory imaging modalities presents a promising avenue in the management of SCD through the development of noninvasive ocular biomarkers to prognosticate progression and measure the response to systemic treatment.

OCT Angiography Features in Diabetes Mellitus Type 1 and 2.

Purpose: To study the foveal avascular zone (FAZ) and the vessel densities (VD) in diabetic patients using optical coherence tomography angiography (OCT-A) and inner retinal layer changes to compare patients affected by type 1 diabetes (DM1) and type 2 diabetes (DM2). Methods: Cross-sectional observational study involving 150 eyes of 150 patients with DM1, and 155 eyes of 155 patients with DM2 with diabetic retinopathy (DR). Retinal nerve fiber layer (RNFL) and Ganglion cell layer (GCL) were evaluated. OCT-A studied both FAZ and VD at the level of the superficial capillary plexus (SCP) and the deep capillary plexus (DCP). Results: A statistically significant difference in FAZ area and foveal VD measured at the SCP (p &lt; 0.001) was noted between DM1 and DM2 groups when comparing patients with mild and moderate non-proliferative diabetic retinopathy (NPDR), while no differences were found in the severe NPDR and proliferative diabetic retinopathy (PDR) subgroups. Duration of diabetes and stage of DR were directly correlated with enlargement of FAZ area and inversely correlated with foveal VD measured at SCP. RNFL and GCL were not different between DM1 and DM2 groups. Conclusion: Changes in OCT-A parameters detected in FAZ area and VD of diabetic patients with different stages of DR may help to predict the risk for progression of the disease.

Functional features in patients with idiopathic macular hole treatment via OCT angiography.

To evaluate the optical coherence tomography (OCT) angiography features in patients with idiopathic macular hole (IMH) before and after vitrectomy. This prospective study included 25 patients diagnosed with IMH in Shanxi eye hospital from August 2019 to December 2021. The study was divided into 3 groups: IMH eyes, fellow eyes and normal eyes. All unilateral IMH eyes underwent vitrectomy. There were significant differences in superficial retinal blood flow density (SRBFD, P < .001) and choroidal blood flow density (CBFD) between IMH and healthy control eyes before operation (P < .05). There was significant difference in SRBFD between fellow eyes and normal eyes (P = .038). The changes of SRBFD and CBFD in IMH eyes before and after operation were statistically significant (P < .05). The CBFD at 6 months after operation is negatively correlated with LogMAR visual acuity, and the CBFD of the fellow eye is also negatively correlated with LogMAR visual acuity. The SRBFD and CBFD had no correlation with the diameter of macular hole before and after operation. SRBFD and CBFD increased after vitrectomy, indicating that the blood supply of retina and choroid were partially restored after vitrectomy. There was no correlation between SRBFD, CBFD and hole diameter, but there was correlation between choroidal blood flow and LogMAR visual acuity.

Combining Optical Coherence Tomography and Optical Coherence Tomography Angiography Longitudinal Data for the Detection of Visual Field Progression in Glaucoma

To use longitudinal optical coherence tomography (OCT) and OCT angiography (OCTA) data to detect glaucomatous visual field (VF) progression with a supervised machine learning approach. Prospective cohort study. One hundred ten eyes of patients with suspected glaucoma (33.6%) and patients with glaucoma (66.4%) with a minimum of 5 24-2 VF tests and 3 optic nerve head and macula images over an average follow-up duration of 4.1 years were included. VF progression was defined using a composite measure including either a "likely progression event" on Guided Progression Analysis, a statistically significant negative slope of VF mean deviation or VF index, or a positive pointwise linear regression event. Feature-based gradient boosting classifiers were developed using different subsets of baseline and longitudinal OCT and OCTA summary parameters. The area under the receiver operating characteristic curve (AUROC) was used to compare the classification performance of different models. VF progression was detected in 28 eyes (25.5%). The model with combined baseline and longitudinal OCT and OCTA parameters at the global and hemifield levels had the best classification accuracy to detect VF progression (AUROC=0.89). Models including combined OCT and OCTA parameters had higher classification accuracy compared with those with individual subsets of OCT or OCTA features alone. Including hemifield measurements significantly improved the models' classification accuracy compared with using global measurements alone. Including longitudinal rates of change of OCT and OCTA parameters (AUROCs=0.80-0.89) considerably increased the classification accuracy of the models with baseline measurements alone (AUROCs=0.60-0.63). Longitudinal OCTA measurements complement OCT-derived structural metrics for the evaluation of functional VF loss in patients with glaucoma.

Optical coherence tomography angiography characteristics of the retinal and optic disc morphology in prolactinoma.

To investigate changes in the retinal and optic disc (OD) morphology in prolactinoma patients without optical chiasmal compression and/or visual field defects using optical coherence tomography angiography (OCTA). In this cross-sectional imaging study, 16 consecutive prolactinoma patients (group 1, 32 eyes) and 15 age- and gender-matched healthy subjects (group 2, 30 eyes) underwent a thorough neuro-ophthalmological examination, which included testing for the presence of any intracranial compressive lesion that could cause optic neuropathy. Retinal morphological parameters, outer retinal and choriocapillaris flow areas, as well as OD vessel density (VD) and retinal nerve fiber layer (RNFL) thickness in for quadrants were then measured using OCTA. Mean age (p=0.537) and gender (p=0.385) of participants in groups 1 and 2 did not differ significantly. The mean BCVA for both groups was 0.00±0.00 logMAR. Microadenomas made up the majority of prolactinomas (87.1%). All retinal morphological parameters in deep capillary plexus (excluding foveal VD) differed significantly between groups 1 and 2 (whole: p<0.001, parafoveal: p=0.021, and perifoveal: p<0.001). Peripapillary RNFL thickness in temporal (p<0.001), nasal (p=0.010), and inferior (p=0.007) quadrants also differed significantly between the two groups. Foveal deep (r=-0.304, p=0.035) and choriocapillaris flow (r=-0.511, p=0.008) were negatively correlated with tumor size at diagnosis. Significant microvascular morphological changes, particularly in the deep retinal layer, as well as in the peripapillary RNFL thickness, were observed in prolactinoma patients. OCTA appears to be capable of detecting non-manifest circumpapillary and even intra-retinal microvascular changes even when there are no obvious signs of prolactinoma-related ocular complications caused by chiasmal compression.

X-linked retinoschisis: OCT-angiography in two brothers from a four-generation family with a p.Arg197Cys pathogenic variant in the RS1 gene.

X-linked juvenile retinoschisis (XLRS) is a rare genetic disease causing retinal splitting. The aim of this work is to describe the optical coherence tomography angiography (OCTA) features in two brothers affected by an hemizygous c.589C>T (p.Arg197Cys) pathogenic variant in exon 6 of the RS1 gene. Each patient underwent a complete ophthalmological examination, including measurement of best corrected visual acuity, slit-lamp biomicroscopy, fundus color photographs, fundus autofluorescence and infrared imaging, fluorescein angiography, spectral-domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA). En Face SD-OCT and OCTA revealed the presence of two different pattern of cystic lesions, fusiform and oval, disposed on a petaloid or irregular manner in the perifoveolar area. A widening of the foveal avascular zone with interruption of the vascular arcades was clearly evident. Furthermore, a capillary drop-out was observed in the superficial plexus of the central retina, other than capillary ectasia in the deep capillary plexus. Straight gray lines were visible among the cysts. OCTA data herein described allow a detailed morphological evaluation of XLRS other than a quantitative assessment of retinal capillary flow in this disease. The retinal alterations that we have reported may be helpful to better understand this rare condition with OCTA being a sensitive technique to monitor the evolution of the disease and the response to potential future therapeutic approaches aimed to restore vision.

Swept-Source OCT Angiography Features in Patients after Macular Hole Surgery.

This study aimed to compare findings of optical coherence tomography (OCT) angiography (OCTA) between eyes with nearly recovered and partially recovered outer retina after full-thickness macular hole (FTMH) surgery and to identify OCTA findings associated with visual acuity. We retrospectively reviewed 30 patients who underwent surgery for idiopathic FTMH. Swept-source OCT (SS-OCT) and OCTA were performed preoperatively and at three and six months postoperatively. Subgroups were divided according to the integrity of the external limiting membranes and ellipsoid zones postoperatively. Correlations of best-corrected visual acuity six months postoperatively with SS-OCT and OCTA measurements were analyzed. There was no difference in preoperative retinal or choroidal vascular index on OCTA between the nearly and partially recovered groups. Six months postoperatively, the choriocapillaris flow-void area was significantly higher in the partially recovered group than in the fellow eye. The nearly recovered group showed better choroidal vascular flow, and vision at six months postoperatively correlated with the ratio of the operated eye’s choriocapillaris flow-void area to the fellow eye. Sufficient choriocapillaris flow on OCTA is associated with better outer retinal recovery and visual outcomes after macular hole surgery.

Retinal Vascular Patterns and Capillary Plexus Reflectivity of Intraocular Tumors; an Optical Coherence Tomography Angiography Study

Purpose To define the vascular characteristics of malignant and benign intraocular tumors by optical coherence tomography angiography (OCTA) and consequently to determine the advantages and disadvantages of the imaging technique in clinical practice. Methods This prospective, descriptive study consisted of choroidal hemangioma, choroidal nevus, choroidal melanoma, ocular melanocytoma, congenital hypertrophy of retinal pigment epithelium (CHRPE), and choroidal osteoma. Retinal angiography images were taken by OCTA in a 6 × 6 mm HD scan protocol. OCTA characteristics were defined by considering different tumor types separately. Results This study included 93 eyes of 90 patients diagnosed with benign or malignant intraocular tumors. The mean age of the patients was 48.9 ± 16.9 years in the hemangioma group, 55.3 ± 12.9 years in the nevus group, 48.2 ± 13.4 years in the melanoma group, 48 ± 18.9 years in the melanocytoma group, 45 ± 22.9 years in the CHRPE group, and 27.8 ± 7.8 years in the osteoma group. We showed four vascular patterns at the level of the choriocapillaris layer in circumscribed choroidal hemangiomas – the appearance of a “bag of worms,” club-like appearance, giant choroidal vessels and normal choriocapillaris. The rates of these vascular patterns were 40%, 30%, 10%, and 20% in treatment-naïve hemangiomas and were 46.1%, 30.8%, 7.7%, and 15.4% in photodynamic therapy-treated hemangiomas, respectively. There was no different vascular structure in the tumor associated with the lesion in the nevus group. There were three different patterns at the choriocapillaris level in the melanomas – a vascular network (10%), avascular areas (30%) and vascular loops (60%). There were some atypical and nonspecific vascular changes demonstrated in the CHRPE and osteoma groups and a fine vascular network was observed in the melanocytoma group. Conclusion The different types of intraocular tumors had specific vascular characteristics which were easily demonstrated by the OCTA machine. This imaging technique can be a useful tool to differentiate these intraocular tumors non-invasively.

Optical coherence tomography angiography as predictor of visual outcomes in retinal vein occlusion treated with antiangiogenic therapy.

Evaluate optical coherence tomography angiography (OCT-A) features in retinal vein occlusions (RVO) associated with visual outcomes after anti-VEGF. Analytical observational study performed in eyes with macular edema secondary to RVO treated with anti-VEGF, with at least 6 months of follow-up. Bradley et al. classification of macular ischemia was used. Logistic regression analysis was used to investigate associations between final best-corrected visual acuity (BCVA) and OCT-A. A total of 62 eyes, 61 subjects, mean age of 70 ± 12,6 years were included. Median follow up time 21,2 months (IQR 24.8), 53,2% had central retinal vein occlusion (CRVO) and 46,8% branch retinal vein occlusion (BRVO). Median BCVA pre-treatment was 0,84 logMAR (IQR 0,83) and post-treatment 0,47 logMAR (IQR 0,52). BCVA improved at the end of follow-up (p = 0,01), as well as central retinal thickness (CRT) (p = 0,02). Regarding capillary densities (CD), there was a decrease for both plexus, Superficial CD (p = 0,01) and Deep CD (p = 0,01), being more involved the superficial plexus. The lower the capillary density in both plexus, the worse BCVA, Superficial CD (r - 0,27, p = 0,03) and Deep CD (r - 0,29, p = 0,02). Media FAZ pre-treatment was 0,30 mm2 (IQR 0,23), with enlargement to 0,37 mm2 (IQR 0,32) (p = 0,01) post-treatment. Preservation of External Limiting Membrane/ Ellipsoid Zone (ELM/EZ) was seen in 60% of subjects (n = 37). The majority had grade 3 macular ischemia. Variables that best explain visual results were, baseline visual acuity (p = 0,01), pre-treatment CRT (p = 0,02) and pretreatment foveal superficial CD (p = 0,02). Variables that best explain final vision after anti-VEGF were baseline visual acuity, CRT and foveal superficial CD.

Correlation of Optical Coherence Tomography Angiography Characteristics with Visual Function to Define Vision-Threatening Diabetic Macular Ischemia.

The thresholds of macular microvasculature parameters associated with mild visual impairment in diabetic macular ischemia (DMI) patients are unclear. Therefore, this prospective observational study is aimed at demonstrating the optical coherence tomography angiography parameters that best correlate with mild visual impairment (<70 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, Snellen equivalent 20/40) in DMI. The study was completed at the Moorfields Eye Hospital from December 2019 to August 2021. A total of 123 eyes of 87 patients with stable-treated proliferative diabetic retinopathy following panretinal photocoagulation were recruited. DMI was defined as an irregular foveal avascular zone (FAZ) area ≥ 0.5 mm2 or a smaller FAZ area with parafoveal capillary dropout in at least one quadrant. The analysis showed that the whole image deep vascular complex vessel density (DVC VD) in the 3 × 3 mm area had the best discriminatory ability to identify participants with mild visual impairment at 41.9% (area under the curve = 0.77, sensitivity 94%, specificity 54%, likelihood ratio [LR] = 2.04), and the FAZ area had the greatest post-test LR = 4.21 at 0.64 mm2. The 3 × 3 mm whole image DVC VD and FAZ area cutoffs are useful for screening vision-threatening DMI, but DVC VD has low specificity.

Morphological and Functional Features in Patients with Idiopathic Macular Hole Treatment.

PurposeTo evaluate the multifocal electroretinogram (mfERG) and optical coherence tomography (OCT) angiography features in patients with idiopathic macular hole (IMH) before and after vitrectomy.Patients and MethodsThis prospective study was conducted at Shanxi Eye Hospital from January 2019 to December 2021. Twenty-five eyes of 25 patients with unilateral IMH, the unaffected fellow eyes, and 30 eyes of healthy patients were investigated. All unilateral IMH eyes underwent vitrectomy.ResultsThe IMH eyes had significantly delayed latency (rings 2–5) of mfERG compared with the healthy control eyes, and the amplitude density of all rings of mfERG was reduced (P < 0.05). When comparing the mfERG components before surgery and at the follow-up, the amplitude density of IMH eyes (ring 1, 3, 4 and 5) was increased significantly (P < 0.05). The delayed implicit times of the second and fifth ring were significantly shortened compared with those of preoperative eyes (P < 0.05). The mean delayed implicit time of mfERG in six months after surgery was negatively correlated with visual acuity (r = −0.890, P = 0.043). Significant differences of superficial retinal blood flow density (SRBFD, P < 0.001) and choroidal blood flow density (CBFD) (P < 0.05) got via OCTA were found between IMH before surgery and healthy control eyes. SRBFD of the fellow eyes were significantly different with the healthy control eyes (P = 0.038). Statistically significance of SRBFD and CBFD changes in IMH eyes were found before and after surgery (P < 0.05).ConclusionIMH eyes had a decreased amplitude density and a delayed implicit time in some regions. Additionally, SRBFD and CBFD were both increased after vitrectomy, which suggests that the blood supply of the retina and choroid is partially restored after vitrectomy.

OCT Angiography Fractal Analysis of Choroidal Neovessels Secondary to Central Serous Chorioretinopathy, in a Caucasian Cohort.

Central serous chorioretinopathy (CSCR) can be complicated by different types of choroidal neovascularization (CNV). The purpose of this study was to investigate the incidence and quantitative optical coherence tomography angiography (OCT-A) features of CSCR-related CNVs. Methods: This was a retrospective multicenter study including 102 eyes of 102 Caucasian patients with acute or complex CSCR. All patients underwent a comprehensive ophthalmological examination. Quantitative OCT-A parameters, including vascular perfusion density (VPD), fractal dimension (FD), and lacunarity (LAC), were measured in CNV eyes. Results: Forty eyes (39.2%) had acute CSCR, whereas the remaining sixty-two (60.8%) had complex CSCR. CNV was observed in 37 (36.27%) eyes, all of which had the complex form. CNVs were classified as type 1 CNV in 11/37 (29.73%) cases and as polypoidal choroidal vasculopathy (PCV) in the remaining 26/37 (70.27%). Overall, the mean VPD, FD, and LAC of CSCR-related CNVs were 0.52 ± 0.20%, 1.44 ± 0.12, and 2.40 ± 1.1, respectively. No significant difference between type 1 CNV and PCV was found. Conclusion: Complex CSCR is often complicated by type 1 CNV and PCV with similar neovascular architecture and branching complexity, a finding supporting the idea that they might be different stages of the same neovascular process. Future OCT-A fractal analysis-based studies that also include other relevant parameters, such as demographics, presentation, morphology on multimodal imaging, and response to treatment, are necessary before drawing any definitive conclusions.