Baseline alterations in blue-on-yellow normal perimetric sensitivity.

Background: the extent of any learning and fatigue effects in blue-on-yellow (B-Y) perimetry is unknown. The within- and between-eye changes in B-Y normal sensitivity at a single visit and between visits was investigated as a function of previous experience in white-on-white (W-W) perimetry and of subject age.
Methods: Sixty-one normal subjects 22 young (range 20-34 years) and 39 elderly (range 51-80 years)-- assigned to one of four groups based upon perimetric experience and age underwent B-Y perimetry on four separate occasions using Program 30-2 of a modified Humphrey Field Analyser 640. Perimetry was performed for both eyes on three consecutive days and again one week later. Global, hemifield and annular mean sensitivities and global short-term fluctuation were calculated for each eye at each visit.
Results: Mean sensitivity was higher in the first eye examined and increased over the 3 days. The increase in mean sensitivity was similar for each eye and was independent of perimetric experience and age. Short-term fluctuation decreased over the 3 days, regardless of eye and experience, but was more pronounced for the younger age group. The extent of all improvements varied considerably between subjects.
Conclusions: Improvements in B-Y perimetric performance occurred as the familiarity with the test increased, regardless of previous W-W experience. Failure to account for such improvement could reduce the efficiency of B-Y perimetry.