Induced intraocular light scatter and the sensitivity gradient of the normal visual field

The influence of intraocular light scatter on the perimetric sensitivity profile of the normal eye was investigated using a series of light-scattering cells containing 0.01%, 0.02% and 0.025% concentrations of 500 nm diameter latex beads. The degree of induced intraocular light scatter was quantified by measuring contrast sensitivity using the Nicolet CS2000 system in the presence and absence of both wide- and narrow-angle glare light. Perimetric sensitivity out to an eccentricity of 30 degrees was assessed, using the Octopus 201 and the Dicon AP3000 automated perimeters, with the three light-scatter cells and in the cell-free control condition. The results for both functions were expressed as the difference between the control response and that recorded under the particular experimental condition. Perimetric attenuation increased with increase in intraocular light scatter; the extent of the attenuation varied with stimulus type, bowl luminance and eccentricity.