Multifocal technique: Difference between revisions

Revision as of 18:44, 22 August 2005

Revision as of 05:44, 7 September 2005

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'''Multifocal techniques''' are used in [[electroretinography|electroretinogram]] and [[visual evoked potential]] recordings to separate the responses originating from the stimulation of different locations in the [[visual field]] (and thus different [[retina|retinal]] locations).

The concept is as follows: Each visual field ___location is stimulated with a [[stimulus]] [[sequence]] that is [[correlation|uncorrelated]] to the sequences used for the other locations. All visual field locations are stimulated in parallel with their individual stimulus sequence. The retinal or cortical activity, which is a mixture of the responses from all visual field locations, is recorded with usual [[electroretinography|electroretinographic]] or [[visual evoked potential]] methods, respectively. Due to the independence of the stimulus sequences, the responses for each visual field ___location can be extracted using mathematical algorithms.

Mutifocal techniques, in particular the multifocal ERG, are used in the [[diagnosis]] of [[ophthalmology|ophthalmological]] diseases.