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S Rauscher, R Vonthein, B Sadowski, B Erdmann, E Krapp, U Schiefer; Computer-Assisted Kinetic Perimetry (CAKP) Using the Octopus 101 Perimeter: Age Related Normal Values of Local Thresholds Using Various Stimulus Conditions and Considering Individual Reaction Times . Invest. Ophthalmol. Vis. Sci. 2002;43(13):3810.
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© ARVO (1962-2015); The Authors (2016-present)
Purpose: To define age-related, almost examiner-independent normative values in regard to localisation and scatter of threshold using CAKP varying stimulus size, luminance and velocity. Methods: The study protocol is set for 84 ophthalmologically and generally healthy subjects between 10 and 79 years. Four different types of stimuli are presented: III 4e at 5°/s, III 4e at 25°/s, I 3e at 5°/s and I 2e at 2°/s, respectively. Stimuli are presented six times along 8 meridians ( 0°, 45°, 90°,..., 315°) using Oct. 101 (INTERZEAG Inc., Switzerland). Local thresholds are defined as mean values (of eccentricities) along each tested meridian. Standard deviation (SD) is used to charcterize local scatter. For each stimulus condition 12 additional stimuli within the central visual field region are presented in order to assess individual reaction time (RT). By that way, local kinetic thresholds can be corrected, considering individual RT. Background luminance is set to 10 cd/m2. We carried out a saturated analysis of variance (F-tests) explaining the RT corrected local thresholds by the factors age group, stimulus and meridian. The following results are related to the age groups of 10-19 and 60-69, respectively. Results: Intraindividual mean SD of local threshold was 6.6. There was no relevant influence of stimulus velocity on threshold localization (difference 1.6° comparing stimulus III 4e at 5°/s 0° meridian to the same stimulus at 25°/s). There was no relevant difference in the eccentricity of the mean local threshold at the nasal side of the visual field (180° meridian) between the age groups for all stimulus conditions.(10-19: 53,6° , 60-69:54,6 ° Stimulus III 4e at 5°/s) However, at the temporal side (0° meridian) the differences of eccentricities between the two groups increased with smaller as well as with dimmer stimuli(difference 0.9° using III 4e at 5°/s and 6.6° using I 2e at 2°/s, p<0,001). Conclusion: CAKP realizes an almost examiner-independent assessment of local kinetic threshold values, which can be corrected for individual reaction time. Repeated presentation of identical stimulus conditions yields further information in regard to local scatter enhancing quality control.
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