Abstract
Purpose :
The aim of this study is to measure the oxygen saturation (SaO2) on the optic nerve of normal subjects and to compare it with patients with glaucoma. Also, the SaO2 will be correlated with different variables affected by glaucoma (RNFL global, MD, IOP, pachymetry)
Methods :
This case-cohort study included 24 participants, They were recruited at The Laurentians Eye Institute (IOL), a multidisciplinary practice in Boisbriand, Quebec. The participants completed an eye exam including the visual acuity, the intraocular pressure (IOP), the pachymetry, the evaluation of the anterior segment with the slit lamp, the gonioscopy and the evaluation of the posterior segment under pupil dilation. An automated visual field (VF) (G-TOP, Octopus) and an optical coherence tomography (OCT) of the optic nerve and the macula (RNFL et Ppole, Spectralis®, Heidelberg Engineering) was obtained. The blood pressure was measured with an automated device and the pulse oximetry were obtained by a pulse oximeter (SpO2). The ocular oximetry measure was acquired by the Zilia imaging system on the temporal side of the optic nerve.
Results :
The result showed a statistically significant difference in the SaO2 values between both groups, t= -2,900, p=0,008, d= -1,184. We also see a statistically significant correlation between the SaO2 values and the global RNFL (r=0.538, p= 0,008, rho = 0,507 p=0,011). There was no significant correlation between the SaO2 and the other variable associated with glaucoma (VF, IOP and pachymetry).
Conclusions :
The SaO2 measured with the Zilia device on the optic nerve is significantly lower in glaucoma patients compared to normal patients. Also, there is a correlation between the value of ocular oximetry and the RNFL measured by OCT. More studies are needed to really establish the role of that device in the diagnostic and follow up of patients with glaucoma.
This is a 2020 ARVO Annual Meeting abstract.