[Intra-individual variability of blue-yellow perimetry].

BACKGROUND

Short wavelength automated perimetry (SWAP) is a sensitive method in detection of early glaucomatous damage. In this study, we compared intra-subject variability of global indices of SWAP and conventional white-on-white perimetry (WWP) in normal clinical conditions (without correction for lens yellowing).

METHODS

SWAP and WWP (Humphrey field analyzer, 24-2 field, full threshold strategy) was performed in 68 eyes with glaucoma or glaucoma suspect and at the same day. The tests were repeated within 45 days (mean follow-up 16 +/- 13 days).

RESULTS

At the follow-up test the mean defect was significantly reduced for both conditions, more pronounced for SWAP. Pattern standard deviation remained statistically equal for both conditions. The coefficient of correlation of baseline to follow-up was for SWAP PSD 0.88 with a slope of 1.05, for WWP PSD 0.7 with a slope of 0.83. The coefficient of variation for PSD was 17% for SWAP and 34% for WWP.

CONCLUSIONS

The low intraindividual variability of SWAP enables early detection of glaucomatous field damage in the follow-up.