Abstract

Visual field defects are often not effectively detected by conventional clinical perimetry despite the presence of extensive pathophysiology in the neuronal pathways.^1-2 In the case of localized retinal lesions resulting from macular degeneration, an accurate assessment of visual dysfunction across the central visual field is even a more formidable task. These uncertainties in the evaluation of visual function stem from our lack of understanding of the basic mechanisms underlying not only the disease processes³, but also the neural signal transmission processes.⁴ Regardless of the exactness of the existing models of neural filtering⁴, the use of grating patches as test-stimuli reveals differential sampling ability of the neuronal units in the presence of a pathology that is undetected by clinical perimetry.^5,6 However, the structural inhomogeneity of the retina imposes further constraints on specific spatio-temporal domain, and the size of the grating patch to be used in detecting visual dysfunction in the local regions of the visual field.

© 1985 Optical Society of America