Lu Chang,1 Dan Li,2 Keyu Zhu,1 Mei Liu,3 Junguo Duan1 

1Chengdu Univerisity of Taditional Chinese Medicine, Chengdu, Sichuan, People’s Republic of China; 2Ningbo Eye Hospital, Wenzhou Medical University, Ningbo, Zhejiang, People’s Republic of China; 3Ankang Hospital of Traditional Chinese Medicine, Ankang, Shaanxi, People’s Republic of China

Correspondence: Junguo Duan, Chengdu University of Traditional Chinese Medicine, No. 37 Shierqiao Road, Jinniu District, Chengdu, Sichuan, 610036, People’s Republic of China, Tel +86 28-68890066 ; +86 13808048959, Fax +86 28-68224933, Email duanjg@cdutcm.edu.cn

Purpose: Investigate the correlation between retinal vascular oxygen saturation and red blood cell parameters, hemorheology parameters in healthy adults.
Methods: The study recruited 120 healthy volunteers, and their elbow venous blood was drawn for examination of RBC parameters and hemorheology. The retinal oximeter measured the retinal vascular oxygen saturation, including retinal arteriolar oxygen saturation (SaO2), venous oxygen saturation (SvO2) and arteriovenous oxygen saturation Difference (AVD). The Pearson Correlation and Spearman’s Correlation methods were used to analyze the correlation between the SaO2, SvO2, AVD and the red blood cell parameters,hemorheology parameters.
Results: The analysis yielded a statistically significant correlation between SaO2 and BMI (r=0.184, P=0.044). SvO2 was associated with Gender (r=− 0.227, P=0.013), HGB (r=− 0.190, P=0.038), HCT (r=− 0.236, P=0.009), RDW-CV (r=0.228, P=0.012), WBRIH (r=0.019, P=0.037), WBVL 1/s (r=− 0.194, P=0.034), WBVM 50/s (r=− 0.206, P=0.024), WBVH 150/s (r=− 0.211, P=0.021) and WBVH 200/s (r=− 0.222, P=0.015). AVD was associated with Gender (r=− 0.318, P=0.000), BMI (r=0.269, P=0.003), RBC (r=0.282, P=0.002), HGB (r=0.263, P=0.004), RBCSI (r=0.187, P=0.041), WBRIH (r=0.289, P=0.001), WBRVH (r=0.247, P=0.006), WBVL 1/s (r=0.220, P=0.016), WBVL 10/s (r=0.289, P=0.001), WBVM 50/s (r=0.323, P=0.000), WBVH 150/s (r=0.320, P=0.000) and WBVH 200/s (r=0.320, P=0.000). Gender (β=− 0.297, P=0.005), BMI (β=0.208, P=0.023), PV (β=− 0.304, P=0.000) were independent predictors of AVD.
Conclusion: Retinal vascular oxygen saturation is correlated with many RBC parameters and hemorheology parameters, indicating that RBC and rheological characteristics of peripheral blood may affect the transport and metabolism of retinal oxygen and are closely related to retinal microcirculation.
Translational Relevance: The relationship between retinal blood oxygen saturation and red blood cell and hemorheology parameters confirmed the close correlation between ocular microcirculation and systemic blood circulation, which provided a prospective diagnosis and treatment strategy for microcirculatory-related eye diseases.

Keywords: retinal vascular oxygen saturation, retinal oximetry, retinal microcirculation, RBC parameters, hemorheology