the purpose of this study was to investigate changes in peripapillary microvasculature using optical coherence tomography angiography (octA) in systemic hypertension (Htn) patients. this was a crosssectional study. Based on the duration of Htn, seventy-eight Htn patients were divided into two groups. (HTN group 1: <10 years, 38 eyes; HTN group 2: ≥10 years, 40 eyes) and 90 control subjects. All subjects underwent 6 × 6 mm OCTA scan centered on the optic nerve head. We analyzed peripapillary vessel density (VD) and perfusion density (PD) in superficial capillary plexus among three groups. The average ganglion cell-inner plexiform layer (GC-IPL) and retinal nerve fiber layer (RNFL) thicknesses of HTN group 2 were thinner than those of the control group (p = 0.016, and 0.035, respectively). HTN group 2 showed lower peripapillary VD and PD than the control group. However, there were no differences between HTN group 1 and the control group in OCT and peripapillary OCTA parameters. In HTN patients, the peripapillary VD, PD and GC-IPL, RNFL thicknesses correlated significantly. octA showed that the peripapillary VD and pD were lower in Htn patients with a duration ≥10 years compared with those of normal controls. peripapillary microvasculature was correlated with the RnfL and GC-IPL thicknesses. HTN duration should therefore be considered when evaluating peripapillary microvasculature using octA.Cardiovascular disease is one of the more common causes of death in developing country, and hypertension (HTN) is the most common treatable risk factor. According to a US study, approximately 68 million (31%) of patients ≥18 years of age are reported to have HTN 1 , and approximately one billion worldwide are affected by HTN 2 . With advances in medical technology, the life expectancy has been extended, and the number of patients with HTN has increased.Uncontrolled HTN can cause vascular changes in many organ systems, such as the brain, heart, kidneys, and eyes, due to elevated arterial pressure and increased peripheral resistance. Vascular changes in the eye can be directly visualized using funduscopy. Arteriolar narrowing is a hallmark of hypertensive retinopathy (HTNR), and the narrowing being characterized as either focal or diffuse. This occurs when the systemic blood pressure rises to maintain constant blood flow by autoregulation of the retinal circulation. The destruction of the inner blood-retinal barrier and vascular endothelial structure can then lead to cotton wool spots, retinal hemorrhage, and intraretinal lipid deposits.Funduscopy, optical coherence tomography (OCT), and fluorescein angiography (FA) may be helpful in the diagnosis and evaluation of retinal pathological changes in HTN. In our previous OCT study, the ganglion cell-inner plexiform layer (GC-IPL) and peripapillary retinal nerve fiber layer (RNFL) thicknesses were lower in chronic HTN and relieved HTNR patients than normal controls 3,4 , Furthermore, in previous optical coherence tomography angiography (OCTA) studies, foveal microvascular perfusion was...

Purpose: To determine the long-term repeatability of optical coherence tomography angiography (OCTA) parameters in normal eyes. Methods: We prospectively enrolled 104 normal eyes. Participants were divided into three groups based on differences in the signal strength (SS) of OCTA scans obtained at two visits at least 6 months apart: group 1, SS difference = 2; group 2, 1; group 3, 0. We measured a foveal centred scan area of 3 3 3 mm pattern. All measurements were performed twice at 5-min intervals at the initial visit. The second measurements were performed at least 6 months later. Results: In short-term vessel density (VD) repeatability, the coefficient of variation (CV) ranged from 3.89% to 8.10% and the intraclass correlation coefficient (ICC) ranged from 0.785 to 0.941. In terms of long-term repeatability, the CV was 5.39-12.62% and the ICC was 0.598-0.867. In group 1, the ICCs of the inner and full VDs were 0.194 and 0.221, respectively. In groups 2 and 3, the ICCs of the inner and full VDs were 0.611 and 0.603, and 0.763 and 0.765, respectively. The central VDs of all groups had high CV besides high ICC.Conclusions: Optical coherence tomography angiography parameters showed good short-term and reasonable long-term repeatability in normal individuals. The differences in SSs between measurements affected such repeatability, so physicians should query the reliability of OCTA parameters when the differences in SS are 2 or more even when the SS is high.

To identify the effects of prolonged type 2 diabetes (T2DM) on changes in peripapillary retinal nerve fiber layer (pRNFL) thickness in patients without clinical diabetic retinopathy. Subjects were divided into two groups: controls and patients with T2DM (DM group). After the initial visits, the pRNFL thicknesses were measured three more times at 1-year intervals. Subgroup analyses were performed in patients with T2DM duration ≥ 10 years. The mean pRNFL thickness at each visit was 95.8 ± 8.1, 95.4 ± 8.3, 94.9 ± 8.1, and 94.5 ± 8.3 μm in the control group (P = 0.138) (n = 55); and 93.4 ± 9.1, 92.1 ± 9.3, 90.9 ± 9.3, and 89.5 ± 9.2 μm in the DM group (P < 0.001) (n = 85). The estimated rate of reduction in mean pRNFL thickness was − 0.45 μm/year in the control group and − 1.34 μm/year in the DM group, respectively. In the DM group, the BCVA and HbA1c (both P = 0.001) were significant factors associated with pRNFL reduction. In patients with T2DM duration ≥ 10 years, the estimated pRNFL reduction rate was − 1.61 μm/year, and hypertension was a significant factor affecting the pRNFL reduction (P = 0.046). We confirmed rapid pRNFL reduction over time in T2DM, and the reduction rate was higher in patients with T2DM ≥ 10 years. Additionally, BCVA and HbA1c levels were significantly associated with the change in pRNFL thickness in T2DM patients.