Retinal oxygen saturation in 1461 healthy children aged 7–19 and its associated factors

Abstract

Purpose The aim of the present study was to investigate age‐specific normative retinal oxygen saturation values and explore the associated factors in healthy Chinese school‐aged children with different refractive statuses. Design Population‐based observational cross‐sectional study. Methods Children aged 7–19 years were enrolled. Each participant underwent a series of comprehensive ocular examinations, including axial length (AL), cycloplegic refraction and Oxymap T1 imagery following cycloplegia. The acquired oximetry images were measured, and the values of the retinal oxygen saturation parameters were calculated. The independent factors of the retinal oxygen saturation were analysed using multiple linear regression. The oxygen saturation of retinal arteries (SaO2) and veins (SvO2) as well as the differences between the arteries and veins (AVD) were measured as the main outcomes. Results In total, 1461 participants were included in the study. The mean age of the participants was 12.1 ± 3.2 years, and 53.0% were boys. The mean SaO2, SvO2 and AVD values were 83.7 ± 6.4%, 50.1 ± 5.4% and 33.6 ± 5.4%, respectively, and the values increased with age. Girls had higher SvO2 and lower AVD than boys (p < 0.05). The Pearson correlation coefficients among spherical equivalent (SE) and SaO2, SvO2 and AVD were −0.372, −0.203 and −0.240, respectively (all p < 0.001), while the correlations between AL and SaO2, SvO2 and AVD were 0.276, 0.106 and 0.221, respectively (all p < 0.001). The myopia group had significantly higher SaO2, SvO2 and AVD than the emmetropia and hyperopia groups (p < 0.001), but the high myopia group had lower SaO2 and SvO2 than the moderate myopia group. When age, gender, body mass index (BMI), intraocular pressure (IOP) and axial length (AL) were included as factors in the multiple regression, older age was associated with higher SaO2, SvO2 and AVD, while longer AL was associated with higher SaO2 and AVD. Gender was an independent factor predicting SvO2, while gender and BMI were the independent factors predicting AVD. Age explained more variance than AL in SaO2, SvO2 and AVD. Conclusions Our population‐based study provides age‐specific profiles of retinal oxygen saturation in Chinese children and adolescents. Older age and longer AL were important independent factors of increased retinal oxygen saturation.

Retinal Vascular Oxygen Saturation and Its Variation With Refractive Error and Axial Length

“…These studies had inconsistent findings regarding the association between retinal arteriolar oxygen saturation and myopia. Our findings of lower retinal arteriolar oxygen saturation in myopia were similar to Zheng et al17 and Chen et al24 The studies by Liu et al18,25 in younger populations, however, both found contrasting trends of higher arteriolar saturation with more myopic refraction and longer AL. One of the key factors affecting the relationship, thus, appears to be age, with studies in adult populations, including our current study, finding lower arteriolar saturation with myopia, and studies in children finding the opposite.…”

“…However, in another cross-sectional study aiming to provide normative data for retinal vessel oxygen saturation levels in 122 young Chinese subjects aged 5 to 18 years with mean refractive error of −3.25 ± 2.49 D (range, −8.88 to +3.13),18 higher retinal arteriolar oxygen saturation levels correlated with more myopic SE. Liu et al25 reported the normative retinal oxygen saturation values in 1461 Chinese children aged 7 to 19 years and found that longer AL was associated with higher arteriolar saturation and AVD. A cross-sectional study by Yang et al20 included subjects aged 19 to 30 and found no significant difference in retinal blood saturation between the group with refractive error less than −3.00 D and the other with refractive error of −3.00 D and above.…”

Morphology and Microcirculation Changes of Optic Nerve Head Between Simple High Myopia and Pathologic Myopia

“…But this compensatory effect disappears immediately when HM occurs, making the retina more prone to pathological changes. Meanwhile, Liu [14] found that the choroid is involved in the transmission of biological signals from retina to sclera, and is involved in the regulation of scleral remodeling and staphyloma. Therefore, more attention should be paid to choroid to assess the progression of PM.…”

Retinal oxygen delivery and extraction in ophthalmologically healthy subjects with different blood pressure status

“…67 VO2 was lower in females than males, on which conflicting evidence exists, and could reflect the lower systemic basal metabolic rate. 47,68 Smoking was also associated with reduced VO2 and could be related to the reported reduced O2 uptake present in other systems. Lastly, although the average, resting OEF was consistent with previous reports, we found that it was lower in smokers.…”