Learning effect of short-wave length automated perimetry in patients with ocular hypertension

Aim: To evaluate the learning effect of short -wavelength automated perimetry (SWAP) on a group of patients with ocular hypertension experienced with standard automated perimetry (SAP). Methods: Thirty patients with ocular hypertension underwent 5 full-threshold SWAP tests at intervals of 7 +/- 2 days. The parameters investigated to detect a learning effect were duration, the perimetric indices, and the number of points with a P of < 5% and 1% in the total and pattern deviation maps. Differences in learning effect were also evaluated by comparing the sensitivities of central, paracentral, and peripheral areas, hemifields and quadrants. Results: Learning effects were demonstrated for mean defect (P < 0.0001, analysis of variance), duration (P = 0.0001), the number of points with P < 5% in the pattern deviation map (P = 0.003), and short fluctuations (P = 0.03). The effect was greater in the peripheral than in central areas (P = 0.04). Mean defect was the most sensitive parameter, for which the learning effect was statistically significant between the first and the fifth test. Conclusions: The results of this study demonstrate a significant learning effect at full-threshold SWAP. This may limit the efficacy of this kind of perimetry in detecting early glaucoma , and should therefore be carefully considered when creating normative databases for new SWAP strategies