Measurement of Eye PO2 using T1 Mapping Has Precision ~8 MmHg & Shows Oxygenation Gradient between Retina & Lens

Nicholas G. Dowell¹, Edward H. Hughes², Paul S. Tofts¹

A new technique is presented that precisely measures T1 (within subject variability ~40 ms) and hence pO2 (precision ~8 mmHg) in the human eye. A pixel-by-pixel calculation of T1 allows the measurement of a T1 and pO2 gradient through the eye that gives useful information about regional variation in oxygenation. We overcome the difficulties of eye movement and image distortion by employing an audio/visual cue for participants and through the careful implementation of the TrueFISP acquisition sequence. This new method of assessing oxygen concentration of the eye will benefit the study of a range of eye conditions such as retinopathy or assessing the therapeutic value of surgical procedures such as vitrectomy (removal and replacement of vitreous humour).