[Assessment of the macula function by static perimetry, microperimetry and rarebit perimetry in patients suffering...

To compare the visual field results obtained by static perimetry, microperimetry and rabbit perimetry in patients suffering from dry age related macular degeneration (AMD).

Fifteen eyes with dry AMD (hard or soft macula drusen and RPE disorders) were enrolled into the study. Static perimetry was performed using M2 macula program included in Octopus 101 instrument. Microperimetry was performed using macula program (14-2 threshold, 10dB) within 10 degrees of the central visual field. The fovea program within 4 degrees was used while performing rarebit perimetry.

The mean sensitivity was significantly lower (p<0.001) during microperimetry (13.5 dB) comparing to static perimetry (26.7 dB). The mean deviation was significantly higher (p<0.001) during microperimetry (-6.32 dB) comparing to static perimetry (-3.11 dB). The fixation was unstable in 47% and eccentric in 40% while performing microperimetry. The median of the "mean hit rate" in rarebit perimetry was 90% (range 40-100%). The mean examination duration was 6.5 min. in static perimetry, 10.6 min. in microperimetry and 5,5 min. in rarebit perimetry (p<0.001). Sensitivity was 30%, 53% and 93% respectively.

The visual field defects obtained by microperimetry were more pronounced than those obtained by static perimetry. Microperimetry was the most sensitive procedure although the most time-consuming. Microperimetry enables the control of the fixation position and stability, that is not possible using the remaining methods. Rarebit perimetry revealed slight reduction of the integrity of neural architecture of the retina. Microperimetry and rarebit perimetry provide more information in regard to the visual function than static perimetry, thus are the valuable method in the diagnosis of dry AMD.