Effects of Bangerter filters on the visual field in visually normal adults: comparison between White-on-White Perimetry and Frequency-Doubling-Technology Perimetry results

Ojective: to investigate the effects of Bangerter filters on the visual field in visually nor-mal adults. Materials and Methods: Thirty eyes of 15 visually normal adults aged 20 to 22 years (median 21 years) were sequentially analyzed with White-on-White standard auto-mated (SAP/W.W.) perimetry and Frequency-Doubling-Technology (FDT) perimetry at the baseline, and with Bangerter filters 0.8 and 0.1. At each filter best corrected visual acuity was measured with E charts at distance. Changes of mean deviation (MD) and pattern standard deviation (PSD) induced by subsequent filters in the visual field as assessed with SAP/W.W perimetry were compared with those found with FDT perimetry. Results: Sub-sequent filters caused progressive degradation of the visual field with either SAP/W.W. and FDT perimetry with some differences between the two techniques. The most relevant and statistically significant difference between SAP/W.W. and FDT perimetry was the greatest increase of PSD in FDT perimetry compared to that of SAP/W.W. perimetry with both 0.8 (SAP/W.W.: 1.47+/-0.20 vs FDT: 3.73+/-1.1) and 0.1 (SAP/W.W.: 1.60+/-0.25 vs FDT: 4.41+/-1.85) filters (p 0.0001). Discussion: Bangerter filters seem to degrade the visual field in visually normal adults. Since the most relevant alterations are seen with FDT perimetry, one can assume a greater effect of filters on a sub-population of cells in the Magnocellular system.