Relation between media disturbances and the visual field
Abstract
The effect of media disturbances on the retinal projection of the external light distribution can be described by means of the so-called point spread function (PSF). The PSF is defined as the retinal light distribution resulting from an external point source. Consequently visual field changes because of media disturbances can be understood if the PSF could be measured. These visual field changes may include sensitivity loss because of increased light scattering in lens or cornea. We have designed a new method to learn more about the pathological PSF than was possible up to now. With this method we are able to measure the part of the PSF outside 1 degree, relative to the central portions of the PSF. Using this method complemented with the help of the modulation transfer function, actual pathological PSF’s were estimated. Considerable changes in the visual field were predicted for relatively mildly disturbed media.
Keywords
Point Spread Function Modulation Transfer Function Central Peak Light Loss Retinal ProjectionPreview
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References
- 1.Aulhorn E, Harms H: Visual perimetry. In: Jameson D, Hurvich LM (eds) Hb of sensory physiology VII/4 Visual psychophysics, pp. 102–145. Springer, Berlin, 1972.Google Scholar
- 2.Brindley GS: Physiology of the retina and visual pathway. Williams and Wilkin, Baltimore, 1970.Google Scholar
- 3.Klewin KM, Radius RL: Background illumination and automated perimetry. Arch Ophthalmol 104: 395–397 (1986).PubMedGoogle Scholar
- 4.Van den Berg TJPT: Importance of pathological intraocular light scatter for visual disability. Doc Ophthal 61: 327–333 (1986).CrossRefGoogle Scholar
- 5.Vos JJ: Verblinding bij tunnelingangen. I. De invloed van strooilicht in het oog. Rapp. IZF 1873 C-8 TNO (English abstract), 1983.Google Scholar
- 6.Vos JJ, Walraven J, Van Meeteren A: Light profiles of the foveal image of a point source. Vis Res 16: 215–219 (1976).PubMedCrossRefGoogle Scholar
- 7.Weale RA: Physical changes due to age and cataract. In: Duncan G (ed) Mechanisms of cataract formation in the human lens. Academic Press, New York, 1981.Google Scholar