Normal gray scale displays in the presence of arcuate scotomas in automated threshold perimetry

In 2.4% of visual fields and 10.4% of eyes with well-established early glaucoma, a normal gray-scale display was present despite an arcuate scotoma on pattern-deviation display in the same central threshold visual-field printout (30-2 single-field analysis program, Humphrey Field Analyzer). Also, the pattern-deviation probability plot highlighted the presence and significance of the arcuate scotoma. To my knowledge these findings have not been previously reported in the literature. In suspected glaucoma or early glaucoma, visual-field analysis based on the gray-scale display alone can be misinterpreted. In this population, the defect-depth or pattern-deviation displays should be examined before any diagnostic or therapeutic decision is made.