Purpose: To identify the effects of prolonged type 2 diabetes (T2DM) on macular microcirculation and the inner retinal layer in diabetic eyes without clinical diabetic retinopathy (DR). Methods: 97, 92, and 57 eyes in the control, patients with T2DM < 10 years (DM group one), and patients with T2DM ≥ 10 years (DM group two) were enrolled. The ganglion cell-inner plexiform layer (GC-IPL) thickness and superficial vessel density (VD) were compared. Linear regression analyses were performed to identify factors associated with VD in T2DM patients. Results: GC-IPL thicknesses in the control, DM group one, and DM group two were 84.58 ± 0.89, 83.49 ± 0.70, and 79.04 ± 0.96 μm, respectively (p < 0.001). The VDs of the full area were 20.32 ± 0.15, 19.46 ± 0.17, and 18.46 ± 0.23 mm−1 (p < 0.001). Post-hoc analyses revealed that the VDs of the full area was significantly different in the control vs. DM group one (p = 0.001), control vs. DM group two (p < 0.001), and DM group one vs. DM group two (p = 0.001). Multivariate linear regression analyses revealed that DM duration (p = 0.037), visual acuity (p = 0.013), and GC-IPL thickness (p < 0.001) were significantly associated with the VD of T2DM patients. Conclusions: We confirmed GC-IPL thinning and decreased superficial VD in the macular areas using OCTA in T2DM patients. Patients with T2DM ≥ 10 years exhibited significantly more severe macular microcirculation impairment compared to patients with T2DM < 10 years and normal controls.

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 The purpose of this study to identify the effects of prolonged type 2 diabetes (T2DM) on the peripapillary retinal nerve fiber layer (pRNFL) and peripapillary microvasculature in patients with prolonged T2DM without clinical diabetic retinopathy (DR). Methods Subjects were divided into 3 groups: controls (control group; 153 eyes), patients with T2DM < 10 years (DM group 1; 136 eyes), and patients with T2DM ≥ 10 years (DM group 2; 74 eyes). The pRNFL thickness and peripapillary superficial vessel density (VD) were compared. Linear regression analyses were performed to identify factors associated with peripapillary VD in patients with T2DM. Results The mean pRNFL thicknesses of the control group, DM group 1, and DM group 2 were 96.0 ± 7.9, 94.5 ± 0.9, and 92.2 ± 8.2 µm, respectively ( P < 0.001). The VDs were 18.24 ± 0.62, 17.60 ± 1.47, and 17.15 ± 1.38 mm −1 in the control group, DM group 1, and DM group 2, respectively ( P < 0.001). In multivariate linear regression analyses, visual acuity (B = −2.460, P = 0.001), axial length (B = −0.169, P = 0.008), T2DM duration (B = −0.056, P < 0.001), and pRNFL (B = 0.024, P = 0.001) were significant factors affecting the peripapillary VD in patients with T2DM. Conclusions Patients with T2DM without clinical DR showed thinner pRNFL and lower peripapillary VD and perfusion density (PD) compared with normal controls, and such damage was more severe in patients with T2DM ≥ 10 years. Additionally, peripapillary VD was significantly associated with best-corrected visual acuity (BCVA), axial length, T2DM duration, and pRNFL thickness in patients with T2DM.

Purpose The purpose of this study was to identify the relationship between the gangion cell-inner plexiform layer (GC-IPL) and retinal vasculature in the context of the progression of diabetic retinopathy (DR). Methods The subjects were divided into four groups according to DR stage: normal controls (group 1), patients with diabetes mellitus (DM) without DR (group 2), patients with mild or moderate nonprogressive DR (NPDR; group 3), and patients with severe NPDR (group 4). GC-IPL thickness, vessel density of superficial vascular plexus (SVD), and the GC-IPL/SVD ratio were compared among the groups. Results A total of 556 eyes were enrolled; 288 in group 1, 140 in group 2, 76 in group 3, and 52 in group 4. The mean GC-IPL thicknesses were 83.57 ± 7.35, 82.74 ± 7.22, 81.33 ± 6.74, and 79.89 ± 9.16 μm in each group, respectively ( P = 0.006). The mean SVDs were 20.40 ± 1.26, 19.70 ± 1.56, 18.86 ± 2.04, and 17.82 ± 2.04 mm −1 in each group, respectively ( P < 0.001). The GC-IPL/SVD ratios were 4.11 ± 0.38, 4.22 ± 0.40, 4.36 ± 0.54, and 4.54 ± 0.55 in each group, respectively ( P < 0.001). In Pearson's correlation analysis, DR stage was significantly correlated with the GC-IPL/SVD ratio (coefficient = 0.301; P < 0.001). Conclusions As the DR stage progressed, the GC-IPL thickness tended to decrease, with the macular SVD showing a significant reduction. Additionally, the impairment of retinal vasculature was more prominent than GC-IPL thinning as DR progressed, which suggests that retinal vasculature changes may precede diabetic retinal neurodegeneration.