ObjectiveTo observe the choroidal vascularity index (CVI) and the subfoveal choroidal thickness (SFCT) of central serous chorioretinopathy (CSC), and to compare the stability and consistency of the two methods of measurement.MethodsA retrospective study. Thirty-one patients with unilateral acute CSC who visited the Department of Ophthalmology of Beijing Friendship Hospital for the first time during the period from Nov 1st, 2016 to Mar 18th, 2018 were included in the study. Thirty-one healthy age-matched subjects were enrolled as controls. All CSC affected eyes and their fellow eyes and healthy eyes were scanned by single-line enhanced depth imaging of OCT through central fovea of macula to measure their SFCT. The image was binarized and then the CVI of a 1500 μm range below fovea was calculated, i.e. the ratio of vascular (or lumen) area to total choroidal area. CVI and SFCT were compared among CSC eyes, fellow eyes and healthy eyes by variance analysis. Intra-group correlation coefficient (ICC), Bland-Altman curve and coefficient of variation (CV) were used to analyze the repeatability, consistency and stability of CVI and SFCT; and Medcalc18.2.1 software was used to draw the Bland-Altman curve and observe the consistency of the two measurement methods.ResultsThere were statistically significant differences in CVI and SFCT between CSC affected eyes and fellow eyes (t=3.470, 2.844; P=0.001, 0.006), CSC affected eyes and healthy eyes (t=6.977, 6.277; P＜0.001,＜0.001), fellow eyes and healthy eyes (t=3.508, 3.433; P=0.001, 0.001). Relative consistency analysis of CVI and SFCT showed that the ICC of single measurement and average measurement of CVI were 0.967 and 0.983 respectively, and that of single measurement and average measurement of SFCT were 0.937 and 0.967 respectively. The consistency of CVI and of SFCT was very good. The ICC value of CVI was slightly higher than that of SFCT. The results of repeatability analysis of CVI and SFCT showed that the difference between the two CVI measurements was smaller, and the difference between the two SFCT measurements was larger. And CVI and SFCT stability analysis results showed that the CV of CVI and SFCT were 10.5% and 25.3% respectively. CVI has smaller CV than SFCT.ConclusionsCompared with healthy eyes, CVI and SFCT are increased in CSC affected eyes and fellow eyes. And compared with SFCT, CVI has better consistency, repeatability and stability.
ObjectiveTo observe the effect of spectral-domain OCT with different subfoveal choroidal areas on choroid vascular index (CVI) in normal healthy eyes.MethodsRetrospective clinical study. From October 2017 to May 2018, 174 eyes of 87 healthy people who visited in the Ophthalmology Department of Beijing Friendship Hospital and had no eye abnormalities were included in the study. All patients received single line scan of macular fovea by enhanced depth imaging OCT. After binary processing of the collected choroidal images, CVI as the center radius of 750, 1500, 3000 and 4500 μm were calculated. Repeated measurement analysis of variance was performed for comparison of CVI between groups.ResultsThe mean values of CVI in the 750, 1500, 3000 and 4500 μm groups were 0.681±0.003, 0.678±0.002, 0.677±0.002 and 0.676±0.002, respectively. The difference between the 750 μm group and the 4500 μm group was 0.005±0.002 (P=0.009). The other pairwise comparison results showed no statistically significant difference (P＞0.05).ConclusionThe CVI is different in healthy eyes with the different distance from macular fovea.
The choroidal vascular index (CVI) is the ratio of the luminal area to the total choroidal area. It can not only reflect the changes in the vascular composition of the choroid, but also serve as an observation index for follow-up treatment effects. CVI is a new biometric tool, which is gradually applied to the observation of choroidal structure in various eye diseases. It has great application prospects in the study of pathophysiological mechanisms, disease process monitoring and efficacy evaluation such as central serous chorioretinopathy, polypoid choroidal vascular disease, age-related macular degeneration, diabetic retinopathy,etc. Understanding the research progress of CVI in various eye diseases can provide reference for clinical research of CVI.
ObjectiveTo observe the peripapillary atrophy (PPA) and peripapillary choroidal vascularity index (CVI) in patients with different degrees of myopia and to analyze their correlations. MethodsA cross-sectional clinical study. From September 2021 to December 2021, 281 mypoic patients of 281 eyes treated in Eye Hospital of Wenzhou Medical University at Hangzhou were included in this study, and the right eye was used as the treated eye. There were 135 eyes in 135 males and 146 eyes in 146 females. The age was 28.18±5.78 years. The spherical equivalent refraction (SE) was －5.13±2.33 D. The patients were divided into three groups: low myopia group (group A, －3.00 D ＜SE≤－0.50 D), moderate myopia group (group B, －6.00 D≤SE≤－3.00 D);high myopia group (group C, SE＜－6.00 D). The spherical equivalent refraction was statistically different among the three groups (H=241.353, P＜0.05). All of the affected eyes were examined by swept-source optical coherence tomography. Combined with B-scan image,assessment and area measurement of β area, γ area (β-PPA and γ-PPA) were carried out on the en-face image. After binarization of the collected images, the nasal, superior, temporal and inferior CVI of the optic disc were calculated. For comparison between groups, one-way ANOVA was used for continuous variables with normal distribution, Kruskal-Wallis test was used for continuous variables with abnormal distribution, and categorical variables were used χ2 inspection. Linear regression analysis was used for the relationship between β-PPA and γ-PPA area and peripapillary CVI of different regions. Linear regression analysis was used to evaluate the relationships between the area of peripapillary atrophy and peripapillary choroidal vascularity index in different regions. ResultsThere was no statistical difference in the incidence of β-PPA among the three groups (χ2=4.672, P=0.097). The incidence of γ-PPA in group A was lower than that in group B anc C, and the difference was statistically different (χ2=33.053, P＜0.001), in which both group A was lower than group B and C. Among the three groups, the area of β-PPA and γ-PPA was statistically significant (H=36.535, 39.503; P＜0.001, 0.001); the β-PPA area of group A and B was lower than that of group C; the γ-PPA area was group A＜group B＜group C. Peripapillary CVI of different regions in group A, group B and group C was statistically significant (F=11.450, 5.037, 6.018, 4.489; P＜0.05). The temporal CVI in group C was lower than that in group A and B; The inferior CVI of group C was lower than that of group A, and the superior and nasal CVI of group B and C were lower than that of group A. In multivariate analysis, SE (β=0.374, P＜0.001), temporal CVI (β=－0.299, P＜0.001) were correlated with the area of β-PPA (adjusted R2=296, P＜0.001); AL (β=0.452, P＜0.001), temporal CVI (β=－0.220, P＜0.001) were correlated with the area of γ-PPA (adjusted R2=0.309, P＜0.001). ConclusionsThe incidence and area of γ-PPA are increased in the higher degree of myopia group. The area of γ-PPA is positively correlated with the axial length, and both the area of β-PPA and γ-PPA are negatively correlated with temporal CVI.