Comparison of Diagnostic Accuracy between Octopus 900 and Goldmann Kinetic Visual Fields

Abstract

Purpose. To determine diagnostic accuracy of kinetic visual field assessment by Octopus 900 perimetry compared with Goldmann perimetry. Methods. Prospective cross section evaluation of 40 control subjects with full visual fields and 50 patients with known visual field loss. Comparison of test duration and area measurement of isopters for Octopus 3, 5, and 10°/sec stimulus speeds. Comparison of test duration and type of visual field classification for Octopus versus Goldmann perimetry. Results were independently graded for presence/absence of field defect and for type and location of defect. Statistical evaluation comprised of ANOVA and paired t test for evaluation of parametric data with Bonferroni adjustment. Bland Altman and Kappa tests were used for measurement of agreement between data. Results. Octopus 5°/sec perimetry had comparable test duration to Goldmann perimetry. Octopus perimetry reliably detected type and location of visual field loss with visual fields matched to Goldmann results in 88.8% of results (K = 0.775). Conclusions. Kinetic perimetry requires individual tailoring to ensure accuracy. Octopus perimetry was reproducible for presence/absence of visual field defect. Our screening protocol when using Octopus perimetry is 5°/sec for determining boundaries of peripheral isopters and 3°/sec for blind spot mapping with further evaluation of area of field loss for defect depth and size.

Detection of Visual Field Loss in Pituitary Disease: Peripheral Kinetic Versus Central Static

“…Combined use of both targets has been recommended in a previous study comparing peripheral static and kinetic programmes. 17 Our third objective considered whether a difference in detection of visual field loss might occur with use of kinetic rather than threshold static perimetry. Visual field results on Octopus kinetic perimetry were compared with age-matched boundaries from the Octopus normative data set.…”

“…A standardised kinetic strategy 17 was programmed into the Octopus 900 perimeters used in this study such that the same programme was used across the two recruitment sites. Two stimuli of the same size (0.25 mm 2 ) were used but of different intensity (I4e, 1000 apostilbs and I2e, 100 apostilbs).…”

“…A minimum of 12 vectors were assessed for the peripheral visual field and 8 for the central visual field inclusive of vectors on and offset from the vertical and horizontal meridia moving centripetally, similar to previously reported testing strategies. 17,18 Where a visual field defect was found, this was further evaluated by examiner intervention using additional vectors, with direction of target movement perpendicular to the boundary of the field defect. Following assessment, the response points along each vector were joined to form the isoptre for I4e and I2e targets, respectively.…”

“…17,18 Visual field results were also graded according to the degree of visual field loss, if any, and ranging from 0 (normal visual field) to 5 (blinding visual field loss). 19 The study protocol consisted of the 30-2 strategy visual field assessment and semi-automated kinetic visual field assessment with Humphrey perimetry and Octopus perimetry on the same day.…”

“…15,16 Static automated perimetry has been shown to be adequate in neuro-ophthalmology practice, whereas kinetic perimetry is useful for patients with severe visual and neurological deficits and patients with peripheral visual field defects. 17,18 In the context of early detection of visual involvement in pituitary tumours, it is important to be able to detect subtle visual field defects, particularly those that arise in the peripheral visual field, which is typically the area of visual field first compromised by pituitary compression. Given the advances in perimetry over recent years, with the current availability of faster thresholding programmes and semi-automated kinetic programmes, the purpose of this study is to compare these methods for diagnostic accuracy in detecting visual field defects due to pituitary disease.…”