Early visual disturbances in glaucoma

Early visual loss in glaucoma may not be detected with conventional perimetry because this technique uses simple spots of light that are perceived by any type of ganglion cells. Visual tests for central or peripheral vision have been designed to more specifically address subsets of cells that are impaired in the early phases of the disease. The rationale for use of these tests and their current clinical evaluation are reviewed in this paper. Many tests assessing different visual pathways give abnormal results in patients with suspected glaucoma and ocular hypertensive patients, favoring the hypothesis that multiple pathomechanisms are involved in the onset of glaucoma.