Zastosowanie półautomatycznej perymetrii kinetycznej (PPK) do oceny ubytków w polu widzenia spowodowanych przez zwyrodnienie barwnikowe siatkówki

Purpose
To assess the applicability of a new technique of kinetic visual field examination – semi-automated kinetic perimetry (SKP) – in patients suffering from the visual field defects due to retinitis pigmentosa.

Material and methods
Thirty-five patients (19 women, 16 men: mean age 38,4 years) suffering from retinitis pigmentosa (10 with with Usher syndrome, one with Bardet-Biedl syndrome and one with Refsum syndrome) were examined using SKP software, implemented in Octopus 101 instrument (Haag-Streit, Koeniz, Switzerland). Three stimuli (III4e and I4e obligatory) were used to assess the hill of vision of each patient. The area of each isopter was measured in deg2. The test time was measured automatically in minutes.

Results
The visual field results were classified as complete or incomplete midperipheral „ring scotoma” (group I – 13 patients) and concentric loss of the visual field (group II – 22 patients). The area of III4e isopter was 6147,5 deg2 in the group I and 1961,7 deg2 in the group II. The area of I4e isopter was 1468,4 deg2 and 781,7 deg2, respectively. The mean test time was 10 min. (range 4-20 min.): 8 min. in the group I and 13 min. in the group II.

Conclusions
There is a large diversity of patterns of the visual field loss in retinitis pigmentosa. SKP, in contrary to widely used manual perimeter, gives a possibility of quantification of the visual field area. Future studies may be able to monitor the progression of the visual field loss caused by retinitis pigmentosa.