Techniques for noninvasively measuring the oxygen saturation of blood in retinal arteries and veins are reported in the literature, but none have been sufficiently accurate and reliable for clinical use. Addressing the need for increased accuracy, we present a series of oximetric equations that explicitly consider the effects of backscattering by red blood cells and lateral diffusion of light in the ocular fundus. The equations are derived for the specific geometry of a scanning-beam retinal vessel oximeter; however, the results should also be applicable to photographic oximeters. We present <i>in vitro</i> and <i>in vivo</i> data that suggest the validity of these equations.
© 2000 Optical Society of America
(170.0170) Medical optics and biotechnology : Medical optics and biotechnology
(170.1470) Medical optics and biotechnology : Blood or tissue constituent monitoring
(170.3660) Medical optics and biotechnology : Light propagation in tissues
(170.4460) Medical optics and biotechnology : Ophthalmic optics and devices
(170.6510) Medical optics and biotechnology : Spectroscopy, tissue diagnostics
Matthew H. Smith, Kurt R. Denninghoff, Arthur Lompado, and Lloyd W. Hillman, "Effect of Multiple Light Paths on Retinal Vessel Oximetry," Appl. Opt. 39, 1183-1193 (2000)