Search

Purpose: To investigate the retinal vessel oxygen saturation in patients with internal carotid artery stenosis (ICAS). Methods: This is a cross‐sectional study. Sixteen patients with unilateral moderate or worse ICAS (≥50%) and no fundus diseases were included in the study. Sixteen gender‐ and age‐matched healthy subjects were selected as controls. The mean oxygen saturation and vessel diameters of the retinal arterioles and venules were obtained using a dual‐wavelength spectrophotometric retinal oximeter. Results: In the eye of the stenotic side, the retinal vessel oxygen saturation was 100.14 ± 10.27% in the arterioles and 56.50 ± 10.79% in the venules, and the arteriovenous (A‐V) difference was 43.63 ± 7.71%. In the eye of the contralateral side, the oxygen saturation was 96.55 ± 7.50% in the arterioles and 57.42 ± 9.84% in the venules, and the A‐V difference was 39.39 ± 6.33%. In healthy subjects, the oxygen saturation was 93.22 ± 5.98% in the arterioles and 56.57 ± 7.05% in the venules, and the A‐V difference was 36.65 ± 7.33%. The arteriolar oxygen saturation in the stenotic side was higher than that in the contralateral side (p = 0.025) and that in the healthy subjects (p = 0.027), and the A‐V difference in the stenotic side was significantly higher than that in the contralateral side (p = 0.009) and that in the healthy subjects (p = 0.013). The diameters of the arterioles in the stenotic side were smaller than those in the healthy subjects (p = 0.030). Conclusions: Patients with ICAS had decreased retinal arteriole diameters and increased retinal vessel oxygen saturation in the arterioles and A‐V differences, suggesting the presence of microcirculation disorder and hyperoxia in the retina. [ABSTRACT FROM AUTHOR]

Purpose: To compare the morphological characteristics of the nailfold capillaries in glaucoma patients with those in healthy subjects. To evaluate the relationship of nailfold capillary morphology with retinal thickness and retinal vessel density in patients with primary open‐angle (POAG) and primary angle‐closure glaucoma (PACG). Methods: Fifty‐one patients with normal‐tension glaucoma, thirty‐two patients with hypertension glaucoma, thirty‐two PACG patients and sixty‐one healthy subjects were included in this cross‐sectional study. Patients with connective tissue diseases or taking anticoagulation or antiplatelet agents were excluded. Nailfold capillaroscopy, spectral‐domain optical coherence tomography and optical coherence tomography angiography were used to evaluate the nailfold capillary morphology, retinal thickness and retinal vessel density, respectively. Results: Nailfold capillary morphological features, including lower capillary density, greater tortuosity, more dilated capillaries >50 μm and more avascular zones >100 μm, were more common in POAG and PACG patients than in control subjects (all p < 0.001). In the POAG group, nailfold vessel density was negatively correlated with ganglion cell complex (GCC) thickness (odds ratio [OR] = 0.908, p = 0.010) and radial peripapillary capillary (RPC) density (OR = 0.787, p = 0.025). Tortuosity degree was negatively associated with RPC density (OR = 0.804, p = 0.016). In the PACG group, no evident relationship between nailfold capillary morphology and retinal thickness or retinal vessel density was detected (all p > 0.05). Conclusions: Nailfold capillary bed abnormalities were observed in both POAG and PACG patients. The nailfold capillary features, especially microvascular density and tortuosity degree, had a significant association with GCC thickness and RPC density in subjects with POAG but not in those with PACG. [ABSTRACT FROM AUTHOR]