Choroidal Volume Research Articles

Factors Associated With Ocular Perfusion Measurements as Obtained With Laser Speckle Contrast Imaging.

To study the ocular and systemic factors affecting optic nerve head (ONH) perfusion data as obtained using a commercially available laser speckle flowgraphy (LSFG) device in a cohort of Caucasian subjects without ocular diseases. Also, to assess the intrasession repeatability and intersession reproducibility of ONH, macular, retinal, and choroidal perfusion. Seventy-five healthy eyes of 75 Caucasian participants underwent LSFG and spectral-domain optical coherence tomography (SD-OCT) on the same visit. Perfusion of the ONH was assessed with LSFG, and SD-OCT was used to measure peripapillary retinal nerve fiber layer thickness (RNFLT) and macular ganglion cell plus inner plexiform layer thickness (GCIPLT). The intrasession repeatability and intersession reproducibility of ONH and macular perfusion and retinal and choroidal relative flow volume (RFV) were evaluated in 20 participants measured on three different days over a 6-month period. Intrasession and intersession intraclass correlation coefficients of LSFG parameters ranged from 0.787 to 0.967 and from 0.776 to 0.935, respectively. Intersession 95% prediction intervals for the ratio of two measurements were wider for RFV indices than for ONH and macular perfusion parameters. The multiple regression analysis indicated that higher ONH perfusion was associated with younger age, female sex, smaller optic disc area, and higher RNFLT. RNFLT was an independent predictor of ONH perfusion, whereas GCIPLT was not. Each 1-µm increase in RNFLT was associated with a 0.272 arbitrary unit increase in ONH perfusion. LSFG measurements of optic disc perfusion are influenced by sex, age, and anatomical variations in optic disc area and RNFLT. Better evaluation of ocular blood flow will result in better diagnosis and treatment of various ocular diseases.

Decreased choriocapillaris vessel density in the ipsilateral eye after carotid artery revascularization detected by widefield SS-OCTA.

ObjectiveTo investigate the short-term blood flow changes and image features of the retina and choroid in patients undergo carotid artery revascularization (CAR) for severe carotid artery stenosis (SCAS) using widefield swept-source optical coherence tomography angiography (SS-OCTA). DesignProspective study. ParticipantsThis prospective study included 112 eyes (56 eyes of the ipsilateral side and 56 eyes of the contralateral side) of 56 participants with severe carotid artery stenosis. MethodsParticipants were examined using widefield SS-OCTA covering an area of 16*16mm centered on the fovea before and after carotid artery revascularization. Retinal parameters including central macular thickness (CMT), vessel density of the retinal superficial vascular complex (VDRSVC), vessel density of the retinal deep vascular complex (VDRDVC), and vessel density of the retina (VDR) and choroidal parameters including central choroidal thickness (CCT), vessel density of the choriocapillaris (VDCC), vessel density of the medium and large choroidal vessels (VDMLC), choroidal vessel volume ratio (CVV/a), and three-dimensional choroidal vascularity index (3D-CVI) were measured. Besides, preoperative and postoperative OCTA images were screened and compared. Main Outcome MeasuresRetinal and choroidal parameters obtained from SS-OCTA. ResultsIn the ipsilateral eye (56 eyes), increase of VDRSVC, VDR, CVV/a, CCT, and 3D-CVI and decrease of VDCC was found after CAR. 13 patients were identified with postoperative ipsilateral choriocapillaris flow voids (PICCFVs) with OCTA images, and presence of PICCFVs was associated with greater postoperative VDCC decrease. In the contralateral eye (56 eyes), we found increase of VDRSVC, VDRDVC, VDR, while no difference of choroidal parameters after CAR and no findings of PICCFVs. ConclusionsFindings of this study suggest that ocular microvascular perfusion is improved after CAR in the ipsilateral eye and the contralateral eye within a wide field of the fundus. The VDCC is decreased in the ipsilateral eye, which may indicate infarctions of choriocapillaris or ischemia-reperfusion injury of the choriocapillaris after CAR.

Long-Term Impact of Carotid Endarterectomy on Choroidal and Choriocapillaris Perfusion: The INFLATE Study

PurposeWhen performed for clinically significant carotid artery stenosis (CAS), the long-term impact of carotid endarterectomy (CEA) on choroidal and choriocapillaris (CC) circulation was studied using swept-source optical coherence tomography angiography (SS-OCTA). DesignProspective observational study. ParticipantsPatients with clinically significant CAS undergoing unilateral CEA. MethodsSS-OCTA scans were performed on both eyes at baseline (before CEA), within one week post-CEA (short-term follow-up [FU]), and at least 30 days post-CEA (long-term FU). Using validated algorithms, we measured mean choroidal thickness (MCT), choroidal vascularity index (CVI), choroidal vessel volume (CVV), CC flow deficit percentage (CC FD%), and CC thickness within the 5mm circle centered on the fovea for both the eye ipsilateral to CEA (surgical side) and the contralateral eye (nonsurgical side). Multivariable regression analysis was conducted to evaluate the impact of baseline demographic and clinical factors on the changes in choroidal and CC parameters. Main Outcome MeasuresBoth the short- and long-term changes in MCT, CVI, CVV, CC FD%, and CC thickness. ResultsThe study included 58 eyes from 29 patients. Significant short-term improvements in MCT (P<0.001) and CC thickness (P=0.006) were observed post-CEA on the surgical side. Long-term FU showed sustained increases in MCT compared with baseline (P=0.02), while CC thickness was not significantly different from baseline (P=0.10). The CVI did not change significantly from baseline at either short-term (P=0.45) or long-term (P=0.22) FU on the surgical side. While CVV demonstrated a short-term rise immediately post-CEA (P<0.001), the difference was not statistically significant at the long-term evaluation (P=0.06). No significant improvement in CC FD% from baseline was observed at any visit post-CEA (short-term P=0.81, long-term P=0.91). The nonsurgical side only showed a significant reduction in CVI at the long-term FU visit compared with before CEA (P=0.01). Clinical variables such as age, degree of stenosis, diabetes, hypertension, and smoking status did not greatly impact the outcomes. ConclusionsUnilateral CEA demonstrated a sustained increase in MCT suggesting persistent improvements in choroidal perfusion in the ipsilateral eye.

Quantitative analysis of three-dimensional choroidal changes in coronary artery disease patients with swept-source optical coherence tomography angiography

PurposeTo quantitatively analyze three-dimensional (3D) choroidal changes in coronary artery disease (CAD) patients with swept-source optical coherence tomography angiography (SS-OCTA) based on a scan area of 12×12mm. Methods236 CAD patients and 78 controls were included after coronary angiography (CAG) evaluation in this prospective cross-sectional study. Choroidal and foveal avascular zone (FAZ) parameters were compared between the two groups. Choroidal morphological characteristics were also evaluated based on ETDRS quadrants. Receiver operating characteristics (ROC) curves were generated to determine the discriminative power of choroidal and FAZ parameters. Linear regression analysis was used to determine the relationships between Gensini score and choroidal parameters. ResultsChoroidal thickness (CT), choroidal vascular volume/ area (CVV/a), and choroidal stromal volume/ area (CSV/a) were significantly reduced in CAD patients, while 2D vascular density decreased only in 1-6mm, and no statistical difference in choroidal vascularity index (CVI) values was detected. The AUC values of choroidal parameters were greater in the inner-6mm area than the outer-6mm area, and good performance was found with a combination with FAZ parameters (AUC=0.77, P<0.001). For morphological analysis, both groups showed the greatest values in superior quadrant and the lowest in nasal quadrant. After controlling for confounding factors, Gensini score was negatively associated with CT (β=-0.35, P=0.003), CVV/a (β=-0.17, P=0.004), and CSV/a (β=-0.18, P=0.005). ConclusionThe SS-OCTA provided excellent visualization and quantification of the choroid and showed decreased choroidal thickness and volume in CAD patients, but the morphological features were unchanged. The severity of coronary artery stenosis was independently associated with choroidal changes.

Quantitative assessment of choroidal parameters in type 1 macular neovascularization linked to central serous chorioretinopathy and neovascular age-related macular degeneration

ObjectiveTo use ultra-widefield swept-source optical coherence tomography angiography (UWF SS-OCTA) to evaluate the choroidal features of neovascular age-related macular degeneration (nAMD) and type 1 macular neovascularization (MNV) attributable to central serous chorioretinopathy (CSC). MethodA cross-sectional research was carried out to examine patients with type 1 MNV due to CSC (50 eyes) and nAMD (98 eyes) utilizing UWF SS-OCTA examinations. The scan procedure covered a vertical 20 mm × horizontal 24 mm region with 9 subfields. A typical set of 68 healthy eyes was used for comparison. The effects of different diagnoses on choroidal parameters were assessed using covariance tests, using gender and age as variables. ResultsThe research showed that all choroidal characteristics were age-related (all p < 0.05). The calculated marginal averages of choroidal thickness (ChT) and choroidal volume (CV) in the central area were substantially lower in the nAMD group than in the CSC group and the normal group after age differences were taken into account (all p < 0.05). In both the superotemporal and temporal areas, the CSC group had a greater choroidal vascular index (CVI) compared to the nAMD group (p < 0.05). Additionally, the CSC group had a greater temporal area choriocapillaris density (CCD) than the nAMD group (p < 0.05). ConclusionAt the choroidal level, type 1 MNV due to CSC and nAMD may be distinguished by UWF SS-OCTA. Compared to the nAMD affected eyes, the CSC affected eyes had increased ChT, CV, CVI, and CCD in several areas. The two diseases could be distinguished based on ChT and CV.

Correlation between choroidal parameters and primary angle-closure suspect in different age groups

ObjectiveTo investigate the correlations between choroidal parameters and primary angle-closure suspect (PACS) in different age subgroups.Methods and analysisParticipants aged 50 years or older in a rural area of Daxing District,...

Vascular Changes and Irreversible Complications in 120° Fundus Using Widefield SS-OCTA in Vogt-Koyanagi-Harada Disease.

To characterize the changes of fundus corresponding to 120° field of view in chronic Vogt-Koyanagi-Harada (VKH) disease in the quiescent phase, and explore the associations with irreversible complications in the fundus utilizing widefield swept source optical coherence tomography angiography (SS-OCTA). Prospective cross-sectional study. Sixty-nine chronic VKH patients (115 eyes) and 55 healthy controls (110 eyes) were included and underwent widefield SS-OCTA. Univariate analyses of variations in retinal and choroidal vessel density (VD), choroidal volume, and choroidal vascularity index (CVI) in VKH patients with different disease durations and the controls were conducted. Logistic regression analysis was employed to identify the associations with irreversible complications including choroidal neovascularization, vasoproliferative tumour of the retina, and chorioretinal atrophy. The Welch's analysis of variance showed lower VD of superficial retina, deep retina, choriocapillaris, and large-sized and medium-sized vessels of the choroid (LMVC), and choroidal volume and CVI in the patients with disease duration > 24 months compared to those with disease duration ≤ 24 months (all P≤0.011). The regression analysis revealed the disease duration (P=0.008; OR=1.02, 95%CI=1.005-1.035) and VD of LMVC (P=0.001; OR=0.707, 95%CI=0.575-0.87) were significantly correlated with the irreversible complications. Chronic VKH patients in the quiescent phase with disease duration > 24 months exhibit more severe decreased VD in each layer of the retina and choroid, reduced choroidal volume and sparse choroidal vascularity compared to those with disease duration ≤ 24 months. Prolonged duration and decreased VD of LMVC were associated with irreversible complications in the fundus.

Association of outer retinal and choroidal alterations with neuroimaging and clinical features in posterior cortical atrophy

BackgroundPosterior cortical atrophy (PCA) is a rare condition characterized by early-onset and progressive visual impairment. Individuals with PCA have relatively early-onset and progressive dementia, posing certain needs for early detection. Hence, this study aimed to investigate the association of alterations in outer retinal and choroidal structure and microvasculature with PCA neuroimaging and clinical features and the possible effects of apolipoprotein E(APOE) ε4 allele on outer retinal and choroidal alterations in participants with PCA, to detect potential ocular biomarkers for PCA screening.MethodsThis cross-sectional study included PCA and age- and sex-matched healthy control participants from June 2022 to December 2023. All participants with PCA completed a comprehensive neurological evaluation. All participants were recorded baseline information and underwent an ophthalmic evaluation. Quantitative analyses were performed using swept-source optical coherence tomography (SS-OCT) and angiography (SS-OCTA). Adaptive optics scanning laser ophthalmoscopy (AO-SLO) was performed in some patients. In participants with PCA, the influence of APOE ε4 on outer retinal and choroidal alterations and the correlation of outer retinal and choroidal alterations with PCA neuroimaging and clinical features in participants with PCA were investigated.ResultsA total of 28 participants (53 eyes) with PCA and 56 healthy control participants (112 eyes) were included in the current study. Compared with healthy control participants, participants with PCA had significantly reduced outer retinal thickness (ORT) (p < 0.001), choriocapillaris vessel density (VD) (p = 0.007), choroidal vascular index (CVI) (p = 0.005) and choroidal vascular volume (CVV) (p = 0.003). In participants with PCA, APOE ε4 carriers showed thinner ORT (p = 0.009), and increased choriocapillaris VD (p = 0.004) and CVI (p = 0.004). The PCA neuroimaging features were positively associated with the ORT, CVI and CVV. Furthermore, differential correlations were observed of PCA clinical features with the CRT, CVV and CVI.ConclusionsOur findings highlighted the association of outer retinal and choroidal alterations with PCA neuroimaging and clinical features in participants with PCA. Noninvasive SS-OCT and SS-OCTA can provide potential biomarkers for the diagnosis and management of PCA, improving awareness of PCA syndrome among ophthalmologists, neurologists, and primary care providers.

The effect of long-term hemodialysis on diabetic retinopathy observed by swept-source optical coherence tomography angiography

BackgroundDiabetes can cause chronic microvascular complications such as diabetic retinopathy (DR) and diabetic nephropathy (DN). DR and DN can lead to or exacerbate diabetic macular edema (DME). Hemodialysis (HD) is the main treatment method for patients with end-stage kidney disease (ESKD) secondary to DN.PurposeThe aim of this prospective cohort study was to determine the immediate effect of single HD session on retinal and choroidal thickness in DR patients with ESKD and the features of DR and the prevalence of DME in these patients who have received long-term HD.MethodsEighty-five eyes of 44 DR patients with ESKD who underwent long-term HD were examined by swept-source optical coherence tomography angiography (SS-OCTA). Based on OCTA images, the characteristics of DR and the prevalence of DME in these patients were analyzed. Changes in central retinal thickness (CRT), central retinal volume (CRV), subfoveal choroidal thickness (SFCT) and subfoveal choroidal volume (SFCV) within 30 min before and after single HD session were compared. CRT, CRV, SFCT and SFCV were compared before single HD session and before the next single HD session.ResultsThere was no significant difference in the average CRT (251.69 ± 39.21 μm vs. 251.46 ± 39.38 μm, P = 0.286) or CRV (0.15 ± 0.62 μm vs. 0.15 ± 0.63 μm, P = 0.324) between before and after single HD session. After single HD session, SFCT (243.11 ± 77.15 μm vs. 219.20 ± 72.84 μm, P < 0.001) and SFCV (0.15 ± 0.10 μm vs. 0.13 ± 0.90 μm, P < 0.001) significantly decreased. There was no statistically significant difference in CRT (251.69 ± 39.21 μm vs. 251.11 ± 38.47 μm, P = 0.206), CRV (0.15 ± 0.62 μm vs. 0.15 ± 0.61 μm, P = 0.154), SFCT (243.11 ± 77.15 μm vs. 245.41 ± 76.23 μm, P = 0.108), or SFCV (0.15 ± 0.10 μm vs. 0.16 ± 0.10 μm, P = 0.174) before HD and before the next single HD session. On en face OCTA images, eighty-five eyes (100%) had retinal nonperfusion areas, foveal avascular zone (FAZ) enlargement, and abnormal retinal microvasculature. Based on cross-sectional OCTA images, retinal neovascularization (RNV) was confirmed in 42 eyes (49.41%), and intraretinal microvascular abnormalities (IRMAs) were detected in 85 eyes (100%). Seventeen eyes (20%) still had DME, all of which were cystoid macular edema (CME). Among eyes with DME, the epiretinal membrane (ERM) was present in 7 eyes (8.24%).ConclusionsFor DR patients with ESKD who have undergone long-term HD, the choroidal thickness still changes significantly before and after single HD session, which may be related to short-term effects such as reduced blood volume and plasma osmotic pressure caused by single HD session. Although macular features seem to have stabilized in DR patients undergoing long-term dialysis, the DR of patients with ESKD should still be given attention.

Association of choroidal thickness and blood flow features with asymmetric axial lengths in children with unilateral myopic anisometropia

BackgroundConsidering that changes in the choroidal thickness are closely related to ocular growth, we studied the choroidal thickness (CT) and the blood flow features in children with unilateral myopic anisometropia (UMA) as well as investigating the relationship between choroidal changes and myopia.MethodsSubjective refractive, axial length (AL), and biometric parameters were measured in 98 UMA children (age: 8–15 years). CT and choroidal blood-flow features, including the choroidal vessel volume (CVV), choroidal vascularity index (CVI), and choriocapillaris perfusion area (CCPA), were measured through swept-source optical coherence tomography angiography. The macular region was categorized into four concentric circles of diameters 0–1 mm (central fovea), 1–3 mm (parafovea), 3–6 mm (perifovea), and 6–9 mm (extended), and further categorized into superior (S), inferior (I), temporal (T), and nasal (N) quadrants.ResultsThe aforementioned four regions of myopic eyes displayed significantly lower CT, CVV, and CVI than those of non-myopic eyes. CCPA changes differed across different regions of both the eyes (parts of N and T quadrants). There was an inverse association between CT and the interocular AL difference (central and other regions S, T quadrant). No correlation was noted between CVV and CVI with interocular AL difference. CT and CVV were positively correlated in the 0–6-mm macular region of myopic eyes (Spearman correlation coefficient = 0.763, P < 0.001).ConclusionsIn UMA children, CCT and blood flow may be related to myopia progression. A robust correlation between CT and CVV in the 0–6-mm macular region and reduced CT and diminished blood flow indicated an association with myopia.

Influence of Carotid Artery Stenting on the Retina and Choroid.

The effect of carotid artery stenting in patients with unilateral carotid artery stenosis on the retina and choroid was evaluated using swept-source optical coherence tomography angiography (SS-OCTA). SS-OCTA examination was conducted before stenting and 4days and 3months after stenting. The retinal nerve fiber layer, ganglion cell-inner plexiform layer (GCIPL), inner nuclear layer, superficial vascular complex (SVC), deep vascular complex (DVC), choroidal vascular volume (CVV), and choroidal vascular index were measured. Repeated-measures analysis of variance was performed to assess the impact of carotid artery stenting on optical coherence tomography angiography (OCTA) metrics. At baseline, 303 eyes from 160 patients (61.82 ± 9.98years; 85.29% males) were enrolled. SVC and DVC densities and CVV were lower in ipsilateral eyes (stenosed side) compared to contralateral eyes (all P < 0.05). Four days after stenting, a significant increase was seen in SVC density in ipsilateral eyes (P < 0.05) while a significant increase was seen in CVV in ipsilateral eyes and contralateral eyes (both P < 0.05). Three months after stenting (63 patients with 114 eyes), a significant decrease was seen in the GCIPL thickness of ipsilateral and contralateral eyes (all P < 0.001). Short term after carotid artery stenting, ipsilateral eyes showed a rapid and significant increase in SVC density and CVV. Optical coherence tomography (OCT)/OCTA measurements may have the potential to detect retinal and choroidal changes after stenting. Future research on the long-term effect of stenting on the retina and choroid will be guided by these findings.

Early and Late Treatment Influence on Chorioretinal Microvasculature in Vogt-Koyanagi-Harada Patients Using Optical Coherence Tomography Angiography.

To study the impact of early and late treatment on chorioretinal microvasculature in Vogt-Koyanagi-Harada (VKH) disease using optical coherence tomography angiography (OCTA). A total of 103 patients with VKH disease were divided into early (group 1, starting treatment within 2months after disease onset) and late (group 2, starting treatment 2months after disease onset) treatment groups. Flow area (FA) and vessel density (VD) of the retinal superficial vascular complex (SVC) and deep vascular complex (DVC), FA of the choriocapillaris, three-dimensional choroidal vascular volume (CVV), and choroidal vascularity index (CVI) were analyzed and compared to 103 healthy individuals. The relationship between the final best-corrected visual acuity (BCVA) and the aforementioned parameters was also analyzed. FA of the SVC (all P < 0.05, except 0-1mm P = 0.087), DVC (all P < 0.05), choriocapillaris (1-2.5mm P = 0.033), and CVV (all P < 0.05) were lower in group 2 as compared to group 1. Compared to healthy controls, FA of the SVC (all P < 0.001, except 0-1mm P = 0.104) and DVC (all P < 0.05), VD of the SVC (1-2.5mm P = 0.001) and DVC (1-5mm P = 0.003, 2.5-5mm P < 0.001), FA of the choriocapillaris (all P < 0.05), and CVV (total area P = 0.049, 1-5mm P = 0.045, 2.5-5mm P = 0.041) were lower in group 2, while FA (all P < 0.05, except 0-1mm P = 0.925) and VD (1-5mm P = 0.003, 2.5-5mm P = 0.004) of the DVC and FA of the choriocapillaris (total area P = 0.007, 0-1mm P < 0.001, 1-2.5mm P = 0.007) were lower in group 1. There was no significant difference concerning CVI among groups (all P > 0.05). FA of the SVC, DVC, and choriocapillaris and VD of DVC and CVI were negatively associated with the final logarithm of the minimum angle of resolution BCVA. Patients with VKH disease who are treated within 2 months of disease onset showed a better chorioretinal microvascular outcome as defined by OCTA compared to those treatedlate. Our study employs OCTA to design three-dimensional metrics for the retina and choroid, bridging the gap between traditional two-dimensional OCTA findings and enhanced clinical outcomes for patients with VKH disease.

Factors affecting choroidal circulation parameters in 4–14-year-old Chinese children measured by SS-OCT/OCTA

PurposeTo measure the choroidal circulatory parameters Han Chinese children aged 4–14 years from Southwest China, and to explore the relationships between these parameters and age, axial length (AL), and choroidal thickness (ChT). Methods284 eyes from 142 subjects were included in this cross-sectional study. All participants underwent cycloplegic refraction and IOLMaster500 examination. Swept-source optical coherence tomography (SS-OCT) was used to measure submacular choroidal thickness, choroidal vascular volume (CVV), choroidal stromal volume (CSV), choroidal vascularity index (CVI), and CVV/CSV ratio. ResultsIn this population, the mean CVV was 2.92 ± 0.55 mm3, CSV was 4.69 ± 0.68 mm3, CVI was 38.22 ± 2.46 %, and CVV/CSV ratio was 62.11 ± 6.44 %. Multivariable regression analyses showed that both CVV and CSV were negatively correlated with AL (both P < 0.001) and positively correlated with ChT (both P < 0.001), while age showed no significant correlation with them (both P > 0.05). However, the correlations between CVI and age were not uniform rectilinear. Among participants aged ≤8 years, CVI showed no correlation with age (P > 0.05), while among those aged >8 years, it was positively correlated with age (P < 0.01). CVV/CSV ratio was positively correlated with ChT and age (both P < 0.01). ConclusionAfter the age of 8, age was positively correlated with CVI. ChT was well correlated with CVI. Longer AL and thinner ChT were associated with reduced CVV and CSV, with CVV decreasing more rapidly than CSV.

COMPARISON OF CHOROIDAL VASCULATURE BETWEEN CENTRAL SEROUS CHORIORETINOPATHY WITH AND WITHOUT THICK CHOROID USING SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

To distinguish between central serous chorioretinopathy (CSC) with and without thick choroid and to elucidate their characteristics of choroidal vasculature. This prospective observational study enrolled 76 eyes with treatment-naive CSC and 76 normal eyes. Mean + 2 times SD of subfoveal choroidal thickness of healthy individuals was set as the upper limit of normal choroidal thickness to divide patients with CSC into two groups: the thick-choroid and non-thick-choroid groups. Their choroid blood flow was compared using widefield swept-source optical coherence tomography angiography. According to the discrimination value of subfoveal choroidal thickness as 326.8 µm, 76 eyes with CSC were divided into the thick-choroid (55, 72.4%) and non-thick-choroid (21, 27.6%) groups. Higher proportions of vortex vein anastomosis were found in the thick-choroid group (81.8% vs. 33.3%, P < 0.001). Choroid thickness, three-dimensional choroidal vascularity index, and mean choroidal stroma volume per 1 mm2 were higher in the thick-choroid group. In multivariate analysis, younger age, higher percentages of vortex vein anastomosis, and double layer sign were the independent predictors of choroid thickening in CSC. There are discrepancies in the degree of choroidal congestion and distribution of vortex veins in the CSC with different choroidal thicknesses.

Diurnal Variation in Choroidal Parameters Among Healthy Subjects Using Wide-Field Swept-Source Optical Coherence Tomography Angiography.

The purpose of this study was to evaluate the diurnal variation in choroidal parameters in a wide field area among healthy subjects and to identify correlations between choroidal luminal area and stromal area and various systemic factors. In this cross-sectional study, 42 eyes from 21 healthy participants (mean age = 32.4 ± 8.8 years) were examined using wide-field swept-source optical coherence tomography angiography (WF SS-OCTA, 24 mm × 20 mm). Measurements of choroidal parameters, including choroidal volume (CV), choroidal thickness (CT), choroidal vessel volume (CVV), and choroidal stromal volume (CSV), were taken at 8:00, 12:00, 18:00, and 22:00. Systemic factors, such as blood pressure and heart rate, were concurrently monitored. Our study observed significant diurnal variations in the mean total CV, CT, CVV, and CSV, with minimum measurements around 12:00 (P < 0.001) and peak values at 22:00 (P < 0.001). Furthermore, changes in CV in specific regions were more closely associated with fluctuations in CVV than CSV in the same regions. No significant diurnal variations were found in systolic (P = 0.137) or diastolic blood pressure (P = 0.236), whereas significant variations were observed in the heart rate (P = 0.001). Our study reveals diurnal variations in choroidal parameters and their associations, emphasizing that changes in choroidal volume relate more to the luminal than the stromal area in vessel-rich regions. This enhances our understanding of choroidal-related ocular diseases. Regions with higher choroidal vasculature observed greater choroidal volume changes.

Unveiling Key Pathological Indicators for Disease Progression in Vogt Koyanagi Harada Disease and Sympathetic Ophthalmia Through Advanced Choroidal Volume Analysis

ABSTRACT Purpose To evaluate the association between quantitative parameters derived from volume analysis of optical coherence tomography (OCT) data and disease worsening in Vogt-Koyanagi-Harada disease (VKHD) and sympathetic ophthalmia (SO). Methods This retrospective study, conducted at Osaka University Hospital, employed swept-source OCT scans from patients diagnosed with VKHD or SO between October 2012 and January 2021. The choroidal vessel structure was segmented and visualized in three dimensions, generating quantitative vessel volume maps. Region-specific choroidal vessel volume (CVV), choroidal volume (CV), and vessel index (VI) were scrutinized for their potential correlation with disease severity. Results Thirty-five eyes of 18 VKHD and 2 SO patient (8 females, 10 males) were evaluated. OCT-derived CVV maps revealed regional CV alterations in VKHD and SO patients. Two parameters, i.e. CV at 3- and 6-month follow-ups (p = 0.044, p = 0.040, respectively, with area under the ROC curve of 0.70) and CVV at 6 months (p = 0.046, area under the ROC curve of 0.71), were significantly higher in recurrent VKHD and SO compared to effectively treated cases. Conclusions The volume analysis of OCT images facilitates a three-dimensional visualization of choroidal alterations, which may serve as a reflection of disease severity in VKHD and SO patients. Furthermore, noninvasive initial CVV or CV measurements may serve as potential biomarkers for predicting disease recurrence in VKHD and SO.

Optical coherence tomography choroidal enhancement using generative deep learning

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

Quantitative assessment of choroidal parameters and retinal thickness in central serous chorioretinopathy using ultra-widefield swept-source optical coherence tomography: a cross-sectional study

ObjectiveIn this study, we used ultra-wide field swept-source optical coherence tomography angiography (UWF SS-OCTA) to assess changes in retinal thickness (RT) and choroidal parameters in individuals who had received a diagnosis of central serous chorioretinopathy (CSC).MethodsThe study encompassed the evaluation of 59 eyes from 47 patients with a diagnosis of CSC, alongside 33 fellow eyes and 31 eyes from healthy individuals (controls). The parameters assessed included RT, choroidal thickness (CT), choriocapillaris density, vascular density of the large choroidal vessel layer, three-dimensional choroidal vascularity index (3D-CVI), choroidal vessel volume per unit area (mCVV/a), and choroidal stroma volume per unit area (mCSV/a).ResultsMetrics including mCVV/a, mCSV/a, 3D-CVI, CT, and RT exhibited significantly elevated values in the eyes affected by CSC compared to those of the control group across nine subfields. Moreover, a substantial number of the subfields in both CSC-affected and fellow eyes exhibited increased values for mCVV/a, mCSV/a, 3D-CVI, CT, and RT when compared with the control group. Additionally, acute and chronic CSC subfields demonstrated significantly elevated values for mCVV/a, mCSV/a, 3D-CVI, CT, and RT in comparison to healthy control eyes. Notably, specific subfields associated with complex and atypical forms of CSC revealed higher metrics compared to those of the control group.ConclusionIn conclusion, the UWF SS-OCTA proved to be a valuable tool for exploring the anatomical etiology and clinical classification and diagnosis of CSC.

Choroidal Vascularity Index and Choroidal Structural Changes in Children With Nephrotic Syndrome.

To investigate the choroidal vascularity index (CVI) and choroidal structural changes in children with nephrotic syndrome. This was a cross-sectional study involving 45 children with primary nephrotic syndrome and 40 normal controls. All participants underwent enhanced depth imaging-optical coherence tomography examinations. An automatic segmentation method based on deep learning was used to segment the choroidal vessels and stroma, and the choroidal volume (CV), vascular volume (VV), and CVI within a 4.5mm diameter circular area centered around the macular fovea were obtained. Clinical data, including blood lipids, serum proteins, renal function, and renal injury indicators, were collected from the patients. Compared with normal controls, children with nephrotic syndrome had a significant increase in CV (nephrotic syndrome: 4.132 ± 0.464 vs. normal controls: 3.873 ± 0.574; P = 0.024); no significant change in VV (nephrotic syndrome: 1.276 ± 0.173 vs. normal controls: 1.277 ± 0.165; P = 0.971); and a significant decrease in the CVI (nephrotic syndrome: 0.308 [range, 0.270-0.386] vs. normal controls: 0.330 [range, 0.288-0.387]; P < 0.001). In the correlation analysis, the CVI was positively correlated with serum total protein, serum albumin, serum prealbumin, ratio of serum albumin to globulin, and 24-hour urine volume and was negatively correlated with total cholesterol, low-density lipoprotein cholesterol, urinary protein concentration, and ratio of urinary transferrin to creatinine (all P < 0.05). The CVI is significantly reduced in children with nephrotic syndrome, and the decrease in the CVI parallels the severity of kidney disease, indicating choroidal involvement in the process of nephrotic syndrome. Our findings contribute to a deeper understanding of how nephrotic syndrome affects the choroid.

Quantitative Evaluation of the Topographical Maps of Three-Dimensional Choroidal Vascularity Index in Children With Different Degrees of Myopia.

To investigate topographical maps of the three-dimensional choroidal vascularity index (3D-CVI) in children with different levels of myopia. We enrolled 274 eyes from 143 children with various severity of myopia, including emmetropia (EM), low myopia (LM), and moderate-high myopia (MHM). The choroidal vessel volume (CVV), choroidal stroma volume (CSV), and 3D-CVI in different eccentricities (fovea, parafovea, and perifovea) and quadrants (nasal, temporal, superior, and inferior) were obtained from swept-source optical coherence tomography angiography (SS-OCTA) volume scans. All choroidal parameters were compared among groups, and the associated factors contributing to different 3D-CVIs were analyzed. Compared to the less myopic group, the more myopic group showed a significant decrease in CVV and CSV (MHM < LM < EM) and a significant increase in the 3D-CVI (MHM > LM > EM) in most areas (all P < 0.05). The nasal quadrant had the greatest 3D-CVI and lowest CSV and CVV, and vice versa in the temporal quadrant. The 3D-CVIs of the EM and LM groups gradually increased from the fovea to the perifovea, whereas the 3D-CVI of the MHM group first decreased and then increased. Regression analysis showed that axial length was an independent risk factor affecting foveal and parafoveal 3D-CVIs. Restricted cubic spline analysis revealed that the 3D-CVI increased with spherical equivalent (SE) when the SE was less than threshold and decreased when the SE was greater than threshold (SE thresholds for foveal, parafoveal, and perifoveal 3D-CVIs were -5.25 D, -5.125 D, and -2.00 D, respectively; all P < 0.05). Children with myopia exhibited decreased CSV and CVV, increased 3D-CVIs, and altered 3D-CVI eccentricity characteristics (from the fovea to the perifovea). The quadratic relationship between the 3D-CVI and SE should be explored in longitudinal investigations.