Computer Assisted Analysis of Macular Function

Kilbride, Paul

Abstract

We propose to use a television ophthalmoscope image processor to assess pathological conditions of the macula that threaten central vision. We have developed a way to measure either rhodopsin or cone pigment density and regeneration time that offers significant advantages over previous methods. Use of digitized images of the ocular fundus enables us to make accurate spatial measurements of the retina. These digitized images can be aligned to correct for eye movement by the subject. This system is particularly helpful in those patients with poor central fixation, since eye movements, specular reflections or retinal structures which would interfere with the measurement can be observed by the operator. Specifically, (1) we propose to determine whether measurement of cone pigment density difference and regeneration time in retinitis pigmentosa patients can be used as prognosticators of future central visual acuity retention. (2) In maculopathies, we propose to determine whether measurement of cone pigment density difference and regeneration time can be used as monitors of the integrity of the photoreceptors in localized retinal areas. We propose to apply these measurements to one naturally occurring and one induced maculopathy: nonexudative """"""""dry"""""""" senile macular degeneration and chloroquine retinopathy. Further, we propose to develop the capabilities of the television ophthalmoscope image processor as an ophthalmoscopic perimeter for assessment of central visual fields in relationship to small retinal or choroidal pathologies noted in maculopathies.