Abstract
Abstract: :
Purpose: To determine the short term fluctuation and to investigate the occurrence of a learning effect in healthy subjects undergoing flicker perimetry. Methods: 20 healthy subjects (mean age: 28.7 + 5.7 years) underwent flicker perimetry with the Octopus 301 (G1 program, Dynamic Strategy) 5 times. The first 3 sessions were separated by an interval of 1 to 30 days, whereas the last 3 sessions were performed within the same day, with 15–minute intervals. The analysis of the first 3 exams was used to investigate the presence of a learning effect. The exam duration, the mean global, foveal, central, and peripheral critical fusion frequencies (CFFs), and the rates of false positive and false negative responses were compared employing analysis of variance for repeated measurements. The mean of the differences between the highest and the lowest CFF value for each tested point during the last 3 tests were used to calculate the short term fluctuation (SF). Results: There were no statistically significant differences among the first three exams regarding the duration, and the rates of false positive and false negative responses (p>0.05). The mean global (p=0.014), central (p=0.008), and peripheral (p=0.03) CFFs were significantly lower in the first exam compared to the second and third exams. The mean foveal CFF was also lower in the first test, although the difference was not statistically significant (p=0.06). The mean global SF was 5.06 + 1.13 Hz, which corresponded to 12.5% of the mean global CFF. Conclusions: This study suggests that flicker perimetry is associated with a learning effect, and that a moderately high short term fluctuation is expected in subjects undergoing such test.
Keywords: visual fields • learning • perimetry