The Study of Normal Visual Fields Using Normal Strategy and Dynamic Strategy in Octopus 101 Automated Perimetery in Korean

Automated static perimeters, which are commonly used for early diagnosis and follow-up of glaucoma patients in Korea, are manufactured overseas, and their basic data were obtained from foreigners and normal values were set to meet them. Therefore, verification of validity of those data should precede their application to Koreans. We compared the mean normal values of standard indices of OCTOPUS 101 automated static perimeter with the values obtained from 140 eyes of 70 healthy Koreans using normal strategy(NS)and dynamic strategy(DS). Mean navlues of mean defect(MD), loss variance(LV), corrected loss variance(CLV), and short-term fluctuation(SF)were: 2.84+/-0.85dB, 2.15+/-0.54dB, 1.22+/-0.42dB, 1.43+/-0.22dBwith NS, and 2.05+/-0.81dB, 1.98 +/-0.58dB, 0.97+/-0.49dB, 1.43+/-0.24dB, repectively with DS. With NS, 114 of 140 eyes (81. 4%)were out of the normal range of MD. With DS, 67 of 140 eyes(47. 9%)were out of normal range of MD, and 2 of 140 eyes(1. 4%)were out of the normal range of SF. Values of the other indices were within normal range of both strategies. Statistical analysis of global indices showed that age was significantly correlated with LV, CLV and SF in NS(P<0.05), and that it was also correlated with LV and CLV in DS(P<0.05). These results suggest that both race and age should be taken into acoount in interpretation of visual fields on automated static perimetry.

A Comparative Analysis of Dynamic Strategy and Normal Strategy in Octopus 101 Perimeter

Dynamic strategy(DS) is a fast threshold algorithm for the Octopus 101 perimeter. To analyze the efficiency of DS, we compared the results of visual field measurements using DS and conventional normal strategy(NS). Subjects comprised 60 eyes of 30 normal individuals in the 3rd decade who has not experienced perimetry before. Program G2 was performed on all subjects at random and enough intervals between the two tests(more than 1 hour). Mean testing time was 1047.63+/-219.38 seconds in NS and 684.98+/-130.95 seconds in DS. Testing time reduction rate was 32.69+/-14.35% on average. Mean defect(MD) was 2.80+/-1.02dB, 2.15+/-0.94dB in the two strategies, respectively. Corrected loss variance(CLV) was 1.31+/-0.50dB2 and 1.03+/-0.61dB2 in each test. There was significant difference in MD and CLV statistically(P0.01). It took less time with DS than NS in Octopus 101 perimeter, but further study will be needed for clinical application of DS.