A clinical comparison of the Friedmann visual field analyser and tangent screen perimetry.

The central visual fields of 44 optometric patients with known or suspected field defects were measured with the Friedmann Visual Field Analyser (FVA) and a 2-m tangent screen. The clinical correlation of visual field characteristics was at least adequate in more than 90% of eyes. Statistically significant correlations were also found between the area of scotoma found on the tangent screen and (1) the number of locations with reduced sensitivity and (2) the average reduction in sensitivity of the stimulated locations as determined by the FVA.