ObjectiveTo observe the correlation between retinal capillary density and retinal thickness in the macula and spherical equivalent (SE) in school-age children. MethodsA cross-sectional study. From May to December 2022, 182 school-age children who visited the ophthalmology department of the First Affiliated Hospital of Zhengzhou University were included . There were 95 males and 87 females. The age ranged from 6 to 12 years, and the spherical equivalent (SE) was +0.50 to －6.00 D. They were divided into three groups based on the SE of the right eyes: 54 eyes in emmetropia group (+0.50≤SE＜－0.50 D), 71 eyes in low myopia group (－0.50≤SE＜－3.00 D), and 57 eyes in moderate myopia group (－3.00≤SE≤－6.00 D). The macular area of 6 mm×6 mm was scanned using swept-source optical coherence tomography angiography and was divided into three concentric rings centered on the fovea, including the macular central fovea (0-1 mm diameter), inner ring (1-3 mm diameter) and outer ring (3-6 mm diameter). The retinal thickness and blood flow density of superficial vascular plexus (SVP) and deep vascular plexus (DVP) in different zones within 6 mm of the macular area were measured. The relationships between SE and SVP, DVP and retinal thickness in each ring region were investigated by univariate and multivariate linear regression analyses, smooth curve fitting, and threshold effects. ResultsThere were significant differences in the SVP (F=6.64, 26.06, 22.69) and DVP (F=7.97, 25.01, 5.09) of macular central fovea, inner ring and outer ring among the emmetropia, low myopia and moderate myopia groups (P＜0.05). Univariate linear regression analysis showed that the SVP (β=－0.56, －1.17, －0.79) and DVP (β=－1.03, －0.93, －0.45) of the three regions were positively correlated with SE (P＜0.05). After smooth curve fitting, threshold effect analysis and multivariate linear regression analysis, the SVP and DVP in the macular central fovea were linearly positively correlated with SE (β=－0.91, －1.40; P＜0.05), and SVP and DVP in the inner ring and outer ring showed an inverted U-shaped curve relationship with SE with the inflection (＜3.00 D). When the SE was less than ＜3.00 D, the SVP and DVP in the inner ring and outer ring were positively correlated with SE (P＜0.05). When the SE was higher than －3.00 D, except for the DVP in the inner ring region, the other parameters were negatively correlated with SE (P＜0.05). There were significant differences in retinal thickness of the inner ring and outer ring (F=5.47, 16.36; P＜0.05), and no significant difference in the macular central fovea among the emmetropia, low and moderate myopia groups (F=2.16, P＞0.05). By using univariate and multivariate linear regression analyses, the retinal thickness in the inner ring and outer ring were negatively correlated with SE (β =1.99, 3.05; P＜0.05). However, no correlation was found between retinal thickness and SE in the macular central fovea (β=－1.65, P＞0.05). ConclusionsIn school-age children with SE between +0.50 D and －6.00 D, the retinal capillaries density of the macular central fovea gradually increase, and increase first and then decrease in the inner ring and outer ring with increasing SE. The retinal thickness of inner ring and outer ring gradually decrease and not change significantly in the macular central fovea.
Objective To observe the hemodynamic changes of posterior polar and peripheral retina and choroid in patients with rheogenic retinal detachment （RRD） after scleral buckling surgery. MethodsA prospective clinical observational study. A total of 25 eyes of 25 patients with RRD who underwent scleral buckle surgery in Tianjin Eye Hospital from February to April 2024 were included in the study. Among them, 10 were male and 15 were female. Age was 17-68 years old. All cases were monocular. The surgical eye and the contralateral healthy eye were divided into the affected eye group and the contralateral healthy eye group respectively. Best corrected visual acuity （BCVA）, scanning source optical coherence tomography angiography （SS-OCTA）, and axial length （AL） measurements were performed 3 months after surgery. SS-OCTA examination of macular area was performed by VG200 of Visual Microimaging （Henan） Technology Co., LTD. Scanning range 21 mm×26 mm. According to the partitioning method of the early treatment group of glycosuria retinopathy, the retina within 21 mm of the macular fovea was divided into concentric circles with the macular fovea as the center and diameters of 1-3, 3-6, 6-12, 12-21 mm, respectively. The built-in software of the device was used to record the central area （12 mm×12 mm in the fovea of the macula） and the peripheral area （12-21 mm range） retinal superficial capillary plexus （SCP）, deep capillary plexus （DCP）, radial peripapillary capillaries （RPC） blood density and choroidal vascular index （CVI）, choroidal vascular volume （CVV）, and 1-3, 3-6, 6-12, 12-21 mm above concentric circles （S）, nasal side （N）, temporal side （T）, and lower side （I） SCP, DCP, and RPC blood flow density. Quantitative data between the two groups were compared by independent sample t test or Wilcoxon signed rank test. The correlation between retinal and choroid blood flow parameters and postoperative BCVA was analyzed by Spearman correlation analysis. ResultsCompared with the opposite healthy eye group, SCP blood density in the central area （Z=－4.372）, DCP blood density in the central area （Z=－2.829）, and CVI in the peripheral area （Z=－2.138） were decreased in the affected eye group, and the differences were statistically significant （P＜0.05）. SCP: in the affected eye group, the blood flow density in T3-6 mm, T6-12 mm, N6-12 mm and T12-21 mm regions decreased, while the blood flow density in I6-12 mm regions increased, with statistical significance （P＜0.05）. DCP: blood flow density in S6-12 mm, I6-12 mm, S12-21 mm and I12-21 mm regions decreased significantly, and the differences were statistically significant （P＜0.05）. RPC: blood flow density decreased significantly in T6-12 mm and I12-21 mm, and the differences were statistically significant （P＜0.05）. CVI: T6-12 mm, S12-21 mm, T12-21 mm, I12-21 mm significantly decreased, and T1-3 mm, S12-21 mm significantly increased, the differences were statistically significant （P＜0.05）. Correlation analysis showed that AL growth was positively correlated with CVV in central region （r=0.408, P=0.040）. The number of pad pressure was negatively correlated with the blood density of central DCP （r=－0.422, P=0.030）. ConclusionsAfter scleral buckling operation, the blood flow density and choroidal blood flow parameters in RRD affected eyes were lower than those in contralateral healthy eyes in some areas. The increase of AL was positively correlated with CVV in the central region, and the wider the range of pad pressure, the worse the recovery of DCP blood density.