title: Improving the quality of multifocal visual evoked potential results by calculating multiple virtual channels.
abstract: OBJECTIVE
  To introduce a method for improvement of multifocal VEP (mfVEP) recordings by prediction of waveforms at multiple positions on the surface of the skull.
  
  
  METHODS
  Fifteen healthy participants (mean age 24 ± 3.8 years) underwent mfVEP recordings from 3 surface positions. Two methods of a best-of-mfVEP approach were used and compared. In the first, a standard procedure, further data from 3 calculated channels were used. In the second approach, mfVEPs were obtained by using data derived from 40 virtual electrode positions on the basis of predictions from dipole source calculations.
  
  
  RESULTS
  The mean signal-to-noise ratios (SNRs) of the best-of-mfVEPs of both methods were compared. The SNR was significantly higher for mfVEP data using additional virtual recordings revealed by dipole source determination (2.87 vs. 3.36; P < 0.035).
  
  
  CONCLUSIONS
  We conclude that multichannel prediction of mfVEP responses based on dipole source calculation significantly improves the quality of the examination results compared with the currently prevalent standard method.
authors.affiliation: Department of Ophthalmology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. bmazinani@gmx.de.
authors.forename: Babac A E
authors.initials: BAE
authors.lastname: Mazinani
authors.affiliation: Department of Neurology, University Hospital RWTH Aachen, Aachen, Germany.
authors.forename: Till D
authors.initials: TD
authors.lastname: Waberski
authors.affiliation: Department of Ophthalmology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany.
authors.forename: Andreas W A
authors.initials: AWA
authors.lastname: Weinberger
authors.affiliation: Department of Ophthalmology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Walter
authors.affiliation: Department of Ophthalmology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany.
authors.forename: Gernot F
authors.initials: GF
authors.lastname: Roessler
mesh_terms: D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011786:Quality Control; D014584:User-Computer Interface; D014787:Vision Tests / Q000295:instrumentation / Q000379:methods*; D014793:Visual Cortex / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*; D055815:Young Adult