Spectral Transmission Characteristics of in vivo Porcine Vitreous

Abstract

Abstract: : Purpose: To determine the spectral properties of porcine vitreous and the spectral transmittance of retinal vessels using intravitreal illumination. Methods: Four adult female swine are anesthetized and are ventilated with 100% oxygen. Each eye is illuminated with a scanning monochromator coupled into a fiber optic probe placed into the vitreous through pars plana. The illuminated fundus is imaged with a modified fundus camera mounted on surgical microscope and the spectral images are obtained at a series of wavelengths in the spectral range of 420 nm to 700 nm wavelength. A standard 3 port pars plana vitrectomy is performed and the same regions of the fundus are imaged using the same bandwidth and wavelength range. Results: Spectra from the areas relatively free of visible retinal blood vessels are averaged. Transmittance for retinal veins and arteries are measured. The spectral transmission of the vitreous is calculated from the data obtained before and after pars plana vitrectomy. Conclusions: The vitreous demonstrates uniform transmittance across the visible spectrum. Extraneous light scattering was diminished after the surgical removal of vitreous.

Keywords: vitreous • imaging/image analysis: non-clinical • retina