REVIEWS   

Minerva Oftalmologica 2005 March;47(1):1-6

Copyright © 2005 EDIZIONI MINERVA MEDICA

language: English, Italian

New non-conventional visual field testing techniques

Brusini P., Zeppier M.

A number of non-conventional visual field testing techniques, which selectively analyze only a part of the visual system, have been proposed in the last few years to overcome the present limits of standard automated perimetry, specifically the poor sensitivity in detecting early visual field defects. High-pass resolution perimetry uses filtered ring-shaped stimuli, in which the stimulus size gradually increases and decreases until threshold level is determined. Short wavelength automated perimetry (SWAP) utilizes a blue stimulus projected on a a highly luminated yellow background in order to saturate the green and red cones. Automated flicker Perimetry measures the critical fusion frequency and selectively analyzes the magnocellular system. Frequency doubling technology perimetry (FDT) employs stimulus patterns of sinusoid gratings (alternate vertical dark and light bars) with a low spatial frequency and a high temporal frequency counterphase flicker. Some techniques study the movement sensitivity mediated by the magnocellular pathway; other methods test functions which have not clearly been defined yet (multi-component perimetry, rarebit perimetry). Lastly, there are also objective testing methods (pupillo-perimetry, multifocal ERG e VEP) which are still in an experimental phase. Non-conventional visual field testing techniques can be of great clinical utility in that they can permit a diagnosis of glaucoma earlier than standard automated perimetry.