title: Associations of retinal oximetry in healthy young adults.
abstract: OBJECTIVE
  To assess factors associated with retinal oximetry values in healthy young adults.
  
  
  METHODS
  Retinal oximetry readings were assessed using the oximetry module of the Vesselmap System in 100 eyes of 50 healthy subjects aged 18 to 58 years. Generalized estimating equation models were used to estimate the associations of candidate variables (age, sex, retinal capillary flow, HbA1c, triglyceride, total cholesterol, ocular perfusion pressure, and finger oxygen saturation [SO2]) with retinal oximetry measures (arteriolar SO2, venular SO2, and the arterio-venous [A-V] difference).
  
  
  RESULTS
  Of the candidate factors assessed, only age and finger SO2 were found to be significantly associated with one or more measures of retinal oximetry in unadjusted analyses. After adjusting for age, sex, and significant factors from unadjusted analyses, age and finger SO2 values remained significant. Age was associated with retinal arteriolar and venular SO2 values (per year increase in age, β = 0.31, 95% confidence interval [CI]: 0.15-0.48 and β = 0.26, 95% CI: 0.08-0.43, respectively), but not associated with the A-V difference. Finger SO2 values were associated with retinal arteriolar SO2 and A-V difference (per percentage change in finger SO2, β = 1.34, 95% CI: 0.40-2.28 and β = 0.74, 95% CI: 0.36-1.11, respectively), but not with venular SO2.
  
  
  CONCLUSIONS
  In healthy young adults, age was positively associated with the retinal arteriolar and venular SO2 values, whereas finger SO2 was positively correlated with greater arteriolar SO2 and A-V difference. Our findings serve as a basis for future studies assessing retinal oximetry values in young adults under normal and pathophysiological conditions.
authors: Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia.
authors: Ryan Eyn Kidd
authors: RE
authors: Man
authors: Muhammad Bayu
authors: MB
authors: Sasongko
authors: Ryo
authors: R
authors: Kawasaki
authors: Jonathan Edward
authors: JE
authors: Noonan
authors: Tiffany Ching Shen
authors: TC
authors: Lo
authors: Chi D
authors: CD
authors: Luu
authors: Ecosse Luc
authors: EL
authors: Lamoureux
authors: Jie Jin
authors: JJ
authors: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D008875:Middle Aged; D010092:Oximetry / Q000379:methods*; D010101:Oxygen Consumption / Q000502:physiology*; D012039:Regional Blood Flow; D012160:Retina / Q000378:metabolism*; D055815:Young Adult
keywords: oxygen saturation; retinal arteriole; retinal oximetry; retinal venule