Abstract
Purpose:
The main objective was to compare Goldmann (GVF; manual) and Octopus (OVF; semi-automated) kinetic visual fields. The study also assessed the test-retest GVF and OVF solid angle measures. Finally the study determined whether Octopus static macular thresholds provided equivalent results to Full-Field Stimulus Threshold (FST; Diagnosys) measures.
Methods:
Twenty-six participants with inherited retinal diseases (IRD; RP or LCA), age range 7 to 52 years, with reduced visual fields (10 deg to 120 deg diameters measured by V4e and one smaller size target, IV4e to I4e) underwent GVF and OVF tests repeated after one week. Octopus macular thresholds with five static points within 5 degrees of fixation and FST measures were obtained and also repeated after one week. Perimetrist ratings assessed fixation, cooperation, fatigue, and reported photopsias.
Results:
All 26 participants maintained fixation with few losses during the perimetry tests. The testing times to determine the two GVF and OVF isopters (V4e and one smaller size) were not significantly different (GVF/OVF median = 22/23 minutes, range = 10-40/6-49 minutes). Solid angle measures (0.2 to 3.2 steradians) from GVF and OVF isopters were not significantly different (paired t-test; p>0.05). Test-retest values (solid angle percent change) were also not significantly different between GVF and OVF with the V4e isopters producing smaller test-retest values (GVF/OVF median = 9.4%/12.8%, range = 0.6%-76.2%/0.2%-62.1%) than the smaller size target isopters (GVF/OVF median = 8.6%/18.1%, range = 0.3%-110.7%/0%-184.5%). Threshold values from FST and Octopus static macular (average or most sensitive) were not correlated. The relationship of participant cooperation, fatigue, and photopsias to results will be discussed.
Conclusions:
Our results provide evidence that OVF semi-automated kinetic perimetry with reaction time compensation can provide similar solid angle measures and similar test-retest variability to GVF performed by a qualified operator in the same testing time. Octopus static macular thresholds are not related to FST values. These findings suggest that OVF can provide reliable and accurate visual field measures in IRD clinical trials and that Octopus static thresholds from the macula do not provide equivalent threshold information to the FST.
Keywords: 758 visual fields •
696 retinal degenerations: hereditary •
642 perimetry