Automated system for testing visual fields

A new generation of algorithms for computerized threshold perimetry, SITA

“…Lynn presented an automated perimeter as early as in 1968 (Fankhauser et al 1972). Early devices usually employed the method of limits for threshold determination, simply altering stimulus intensities from infra-, or supraliminal until the threshold was crossed (Chaplin et al 1973;Heijl & Krakau 1975). This first generation of algorithms was soon replaced with more sophisti- Test accuracy, measured as average MSE (a) and average number of stimulus exposures @), vs. deviations of threshold estimates required to start second staircases.…”

Using high-density perimetry to explore new approaches for characterizing visual field defects

“…At first, visual assessment of thresholds obtained from static automated perimetry imitated isopters ( Heijl & Krakau, 1975b , 1975a ) or used a grayscale at each location to represent thresholds ( Chaplin et al, 1973 ), then used interpolated grayscale images and finally non-interpolated grayscales that represent the threshold as a percentile of the value expected at each location based on age norms and global indices based on those ( Flammer, 1986 ; Heijl et al, 1987 ). Over time, static automated perimetry replaced manual kinetic perimetry for most clinical uses.…”

Mathematical optimization of glaucoma visual field screening protocols

“…In addition, several automated computerized instruments for the presentation of visual field stimuli and the recording of patient responses have recently become available (Fankhauser et al, 1972;Spahr & Fankhauser, 1974;Chaplin et al, 1973;Jernigan, 1974;Lynn & Tate, 1975;Heijl & Krakau, 1975). Several investigators have suecessfuUy utilized these and other devices to develop screening protocols for mass visual field investigations of supposedly normal subjects (Greve & Verduin, 1972) and for the detection of early visual field loss in patients suspected of having glaucoma Rock et al, 1971 ;Heijl, 1976).…”