Purchase this article with an account.
Alex David Pechauer, Yali Jia, Liang Liu, Simon S Gao, Chunhui Jiang, David Huang; Optical Coherence Tomography Angiography of the Peripapillary in Response to Hyperoxia. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):3361.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Compare the peripapillary perfusion in healthy subjects before and after hyperoxia using a commercially available optical coherence tomography (OCT) system.
Participants were imaged after a 10 minute exposure to normal and then hyperoxic breathing conditions. One eye of each subject was scanned twice by a high-speed (70 kHz) 830 nm wavelength spectrometer-based OCT system. The optic disc region was scanned using a 3x3 mm volumetric scan. The split-spectrum amplitude decorrelation angiography (SSADA) algorithm was used to compute 3D angiograms. Horizontal and vertical-priority scans were registered and merged to obtain one motion-corrected angiogram (Fig 1). The flow index (FI) was the average decorrelation value of the peripapillary on the en face angiogram. The vessel density (VD) was the percent area occupied by vessels in the peripapillary.
Six healthy participants were scanned. The FI at baseline was 0.108 ± 0.011 (mean ± SD), which was significantly more (P = 0.001, T-test) than hyperoxia (0.099 ± 0.011). There was a significant difference (P = 0.007, T-test) in VD between baseline (95.9 ± 2.23) and hyperoxia (93.3 ± 3.43). Repeatability coefficient of variation (CV) for baseline FI was 5.75% and for VD 1.67%. The reproducibility CV for baseline FI and VD was found to be 11.1% and 1.14%, respectively. Each participant had a large variation in between-day autoregulatory response (Fig 2). The hyperoxia induced average percent change relative to the baseline mean had a reproducibility CV of 44.7% for FI and 75% for VD.
Using SSADA OCT we have shown that peripapillary microvasculature blood flow can be measured under both normal and hyperoxic conditions using a commercially available OCT system. The decrease in peripapillary perfusion in response to an increase in oxygen partial pressure provides further evidence of retinal autoregulation. The autoregulatory response varied between days.
This PDF is available to Subscribers Only