• We selected for study 35 patients with glaucomatous visual field loss or cupping that was asymmetric between the two eyes, concentrating on cases in which the glaucomatous damage was mild. We found that 15 patients had a reduced foveal sensitivity usually associated with either a scotoma impinging on fixation or a depression in the central field. In addition, 19 of the 35 patients had a subtle reduction in visual acuity. Thus, the fovea is often mildly affected early in glaucoma, even though the point of fixation is typically among the last regions of visual field to have a severe loss of visual sensation. We also observed that there is often a diffuse visual field loss early in glaucoma, represented as a generalized depression, and this may occur before there are discrete nerve fiber-bundle defects (paracentral scotomas and the like).
Anctil J, Anderson DR. Early Foveal Involvement and Generalized Depression of the Visual Field in Glaucoma. Arch Ophthalmol. 1984;102(3):363-370. doi:10.1001/archopht.1984.01040030281019