A novel, dynamic, in vivo, non-contact method of measuring oxygen depletion rate of the anterior eye

PurposeDespite the importance of oxygen measurements, techniques have been limited by their invasive nature and small corneal area of assessment. The aim of this study was to assess a non-contact way of measuring oxygen uptake of the whole anterior eye.MethodThe device consisted of a goggle with an oxygen sensitive material on the inner surface. As the output is affected by temperature, a second probe was inserted into the goggle to compensate. The goggle was positioned over the eye on 10 subjects (mean age 30.5 ± 5.0 years, 3:2 male:female) to assess the oxygen depletion of the unrestricted, blinking eye. Measurements were taken over a 3 min period. The volume contained within the goggle and bone structure of individual eyes was measured by water volume displacement and the output corrected to O2% reduction/cm3 over a 30 s period. To check the discriminatory ability of the device, measurements were taken in open-eye and closed-eye conditions, along with on the subjects’ skin (cheek) for comparisons.ResultsThe oxygen depletion measure over 30 s was on average 3.10 ± 1.51 O2% cm3 during open eye condition, significantly more than during closed eye conditions (1.26 ± 1.52 O2% cm3). The skin (control) showed a negligible oxygen uptake (0.19 ± 0.33 O2% cm3). The results demonstrated good repeatability with a mean standard deviation of around 0.4 O2% cm3 (equating to 11%).ConclusionsThe technique demonstrated a non-invasive, non-contact method of measuring consumption of oxygen within the goggle (oxygen depletion rate) and showed good within-visit repeatability.