短期高海拔暴露对世居海平面青年脉络膜循环的影响OA

Objective To investigate the effects of short-term high-altitude exposure on choroidal blood flow in healthy adults residing at sea level.Methods This prospective observational study included 9 healthy sea level-residing volunteers.Optical coherence tomography angiography was performed at eight time points:baseline at sea level,on days 2,4,7,and 10 of high-altitude exposure,and on days 3,5,and 9 after returning to sea level.Bilateral choroidal parameters,including choroidal thickness,choroidal stromal volume,choroi-dal vascular volume,choroidal vascularity index,and choriocapillaris flow density,were quantitatively ana-lyzed.Linear mixed-effects models were employed for statistical analysis.Results Choroidal stromal volume was significantly elevated on day 2 of high-altitude exposure(P<0.05),peaked on day 10,and decreased by day 3 after returning to sea level,showing no significant difference from baseline.choroidal vascular volume and choroidal vascularity index decreased significantly from day 2 of exposure(P<0.05),remained at this reduced level on days 4,7,and 10 with no difference from day 2,and returned to baseline levels by day 3 after returning to sea level(P>0.05).choriocapillaris flow density exhibited a transient significant increase only on day 3 of exposure(P<0.05),with no significant difference at other time points compared to baseline.Mean choroidal thickness showed no significant changes throughout the exposure and post-return periods.Conclusion Short-term high-altitude exposure induces alterations in choroidal blood flow in healthy sea lev-el-residing adults,which are reversible upon descent to sea level.