Evaluation of choroidal substructure perfusion in patients affected by systemic sclerosis: an optical coherence tomography angiography study.

Objective: Vasculopathy in systemic sclerosis (SSc) is characterized by the obliteration of arterioles and a reduced capillary density in various tissues. In SSc, atrophic alterations of the choroid have been suggested based on morphological data acquired by optical coherence tomography (OCT). In this study, we aimed to assess the choroid in eyes of patients with SSc from a microcirculatory, dynamic point of view by adding optical coherence tomography angiography (OCTA) to the diagnostic spectrum.Method: SSc patients were enrolled, and age- and gender-matched healthy subjects were used as controls. In addition to basic ophthalmological and rheumatological examinations, individuals underwent enhanced-depth imaging OCT and OCTA. Subfoveal thicknesses of the choroid as well as all three choroidal vascular sublayers were measured and submacular perfusion values were evaluated.Results: In total, 12 patients with SSc and 12 matched controls were included. The median age of participants was 64 years. Submacular perfusion was significantly lower in the choriocapillaris (Δ = 0.72%; p = 0.045), Sattler's layer (Δ = 2.87%; p = 0.001), and Haller's layer (Δ = 2.69%; p = 0.018) of SSc patients compared to controls. Subfoveal thicknesses of Sattler's layer (Δ = 15 µm; p = 0.026) and Haller's layer (Δ = 41 µm; p = 0.045) were also significantly smaller in the SSc group.Conclusion: Choroidal microcirculation is impaired in SSc, even in patients without ophthalmological symptoms. Choroidal OCT and OCTA may offer additional biomarkers for SSc activity.

Influence of hyperoxia on diastolic myocardial and arterial endothelial function.

OBJECTIVE: Hyperoxia is known to influence cardiovascular and endothelial function, but it is unknown if there are differences between younger and older persons. The aim of this study was to monitor changes in myocardial diastolic function and flow-mediated dilatation (FMD) in younger and elderly volunteers, before and after exposure to relevant hyperbaric hyperoxia. METHODS: 51 male patients were separated into two groups for this study. Volunteers in Group 1 (n=28, mean age 26 ±6, "juniors") and Group 2 (n=23, mean age 53 ±9, "seniors") received standard HBO2 protocol (240kPa oxygen). Directly before and after hyperoxic exposure in a hyperbaric chamber we took blood samples (BNP, hs-troponin-t), assessed the FMD and echocardiographic parameters with focus on diastolic function. RESULTS: After hyperoxia we observed a high significant decrease in heart rate and systolic/diastolic FMD. Diastolic function varied in both groups: E/A ratio showed a statistically significant increase in Group 1 and remained unchanged in Group 2. E/e' ratio showed a slight but significant increase in Group 1, whereas e'/a' ratio increased in both groups. Deceleration time increased significantly in all volunteers. Isovolumetric relaxation time remained unchanged and ejection fraction showed a decrease only in Group 2. There were no changes in levels of BNP and hs-troponin-t in either group. CONCLUSION: Hyperoxia seems to influence endothelial function differently in juniors and seniors: FMD decreases more in seniors, possibly attributable to pre-existing reduced vascular compliance. Hyperoxia-induced bradycardia induced a more pronounced improvement in diastolic function in juniors. The ability of Group 1 to cope with hyperoxia-induced effects did not work in the same manner as with Group 2.