Documenta Ophthalmologica

, Volume 135, Issue 3, pp 209–218 | Cite as

VEP-based acuity assessment in low vision

  • Michael B. HoffmannEmail author
  • Jan Brands
  • Wolfgang Behrens-Baumann
  • Michael Bach
Original Research Article



Objective assessment of visual acuity (VA) is possible with VEP methodology, but established with sufficient precision only for vision better than about 1.0 logMAR. We here explore whether this can be extended down to 2.0 logMAR, highly desirable for low-vision evaluations.


Based on the stepwise sweep algorithm (Bach et al. in Br J Ophthalmol 92:396–403, 2008) VEPs to monocular steady-state brief onset pattern stimulation (7.5-Hz checkerboards, 40% contrast, 40 ms on, 93 ms off) were recorded for eight different check sizes, from 0.5° to 9.0°, for two runs with three occipital electrodes in a Laplace-approximating montage. We examined 22 visually normal participants where acuity was reduced to ≈ 2.0 logMAR with frosted transparencies. With the established heuristic algorithm the “VEP acuity” was extracted and compared to psychophysical VA, both obtained at 57 cm distance.


In 20 of the 22 participants with artificially reduced acuity the automatic analysis indicated a valid result (1.80 logMAR on average) in at least one of the two runs. 95% test–retest limits of agreement on average were ± 0.09 logMAR for psychophysical, and ± 0.21 logMAR for VEP-derived acuity. For 15 participants we obtained results in both runs and averaged them. In 12 of these 15 the low-acuity results stayed within the 95% confidence interval (± 0.3 logMAR) as established by Bach et al. (2008).


The fully automated analysis yielded good agreement of psychophysical and electrophysiological VAs in 12 of 15 cases (80%) in the low-vision range down to 2.0 logMAR. This encourages us to further pursue this methodology and assess its value in patients.


Visual acuity Objective assessment Visual evoked potentials Low vision Sweep VEP Step VEP 


Compliance with ethical standards

Conflict of interest

All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent–licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.

Statement of human rights

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Statement on the welfare of animals

This article does not contain any studies with animals performed by any of the authors.

Informed consent

Informed consent was obtained from all individual participants included in the study.


  1. 1.
    Holder GE (2006) Electrodiagnostic testing in malingering and hysteria. In: Heckenlively J, Arden G (eds) Principles and practice of clinical electrophysiology of vision. MIT Press, Cambridge, London, pp 637–641Google Scholar
  2. 2.
    Katsumi O, Arai M, Wajima R et al (1996) Spatial frequency sweep pattern reversal VER acuity vs Snellen visual acuity: effect of optical defocus. Vis Res 36:903–909CrossRefPubMedGoogle Scholar
  3. 3.
    Arai M, Katsumi O, Paranhos FR et al (1997) Comparison of Snellen acuity and objective assessment using the spatial frequency sweep PVER. Graefes Arch Clin Exp Ophthalmol 235:442–447CrossRefPubMedGoogle Scholar
  4. 4.
    Ridder WH III (2004) Methods of visual acuity determination with the spatial frequency sweep visual evoked potential. Doc Ophthalmol 109:239–247CrossRefPubMedGoogle Scholar
  5. 5.
    Bach M, Maurer JP, Wolf ME (2008) Visual evoked potential-based acuity assessment in normal vision, artificially degraded vision, and in patients. Br J Ophthalmol 92:396–403. doi: 10.1136/bjo.2007.130245 CrossRefPubMedGoogle Scholar
  6. 6.
    Mackay AM, Bradnam MS, Hamilton R et al (2008) Real-time rapid acuity assessment using VEPs: development and validation of the step VEP technique. Investig Ophthalmol Vis Sci 49:438–441CrossRefGoogle Scholar
  7. 7.
    American Foundation for the Blind (2008) Key definitions of statistical terms—American Foundation for the Blind. Accessed 17 Dec 2016
  8. 8.
    World Health Organisation (2016) ICD-10 Version:2016. Accessed 3 Jun 2017
  9. 9.
    Tyler C, Apkarian P (1982) Properties of localized pattern evoked potentials. In: Bodis-Wollner I (ed) Evoked Potentials. The New York Academy of Sciences, New YorkGoogle Scholar
  10. 10.
    Strasburger H (1987) The analysis of steady state evoked potentials revisited. Clin Vision Sci 1:245–256Google Scholar
  11. 11.
    Bach M, Joost W (1989) VEP vs spatial frequency at high contrast: Subjects have either a bimodal or single-peaked response function. In: Kulikowski J, Dickinson C, Murray I (eds) Seeing contour and colour. Pergamon Press, Oxford, pp 478–484Google Scholar
  12. 12.
    Parry NR, Murray IJ, Hadjizenonos C (1999) Spatio-temporal tuning of VEPs: effect of mode of stimulation. Vis Res 39:3491–3497CrossRefPubMedGoogle Scholar
  13. 13.
    Meigen T, Bach M (1999) On the statistical significance of electrophysiological steady-state responses. Doc Ophthalmol 98:207–232CrossRefPubMedGoogle Scholar
  14. 14.
    Norcia AM, Tyler CW, Hamer RD, Wesemann W (1989) Measurement of spatial contrast sensitivity with the swept contrast VEP. Vis Res 29:627–637CrossRefPubMedGoogle Scholar
  15. 15.
    Norcia AM, Clarke M, Tyler CW (1985) Digital filtering and robust regression techniques for estimating sensory thresholds from the evoked potential. IEEE Eng Med Biol Mag 4:26–32CrossRefPubMedGoogle Scholar
  16. 16.
    Tyler CW, Apkarian P, Levi DM, Nakayama K (1979) Rapid assessment of visual function: an electronic sweep technique for the pattern visual evoked potential. Investig Ophthalmol Vis Sci 18:703–713Google Scholar
  17. 17.
    Jägle H, Zobor D, Brauns T (2010) Accommodation limits induced optical defocus in defocus experiments. Doc Ophthalmol 121:103–109. doi: 10.1007/s10633-010-9237-y CrossRefPubMedGoogle Scholar
  18. 18.
    Heinrich SP, Krüger K, Bach M (2010) The effect of optotype presentation duration on acuity estimates revisited. Graefes Arch Clin Exp Ophthalmol 248:389–394. doi: 10.1007/s00417-009-1268-2 CrossRefPubMedGoogle Scholar
  19. 19.
    World Medical Association (2000) Declaration of Helsinki: ethical principles for medical research involving human subjects. J Am Med Assoc 284:3043–3045CrossRefGoogle Scholar
  20. 20.
    Bach M (2007) The freiburg visual acuity test—variability unchanged by post hoc re-analysis. Graefes Arch Clin Exp Ophthalmol 245:965–971CrossRefPubMedGoogle Scholar
  21. 21.
    Bach M (1996) The freiburg visual acuity test—automatic measurement of visual acuity. Optom Vis Sci 73:49–53CrossRefPubMedGoogle Scholar
  22. 22.
    Heinrich TS, Bach M (2001) Contrast adaptation in human retina and cortex. Investig Ophthalmol Vis Sci 42:2721–2727Google Scholar
  23. 23.
    Bach M, Meigen T, Strasburger H (1997) Raster-scan cathode-ray tubes for vision research—limits of resolution in space, time and intensity, and some solutions. Spat Vis 10:403–414CrossRefPubMedGoogle Scholar
  24. 24.
    Odom JV, Bach M, Brigell M et al (2016) ISCEV standard for clinical visual evoked potentials: (2016 update). Doc Ophthalmol 133:1–9. doi: 10.1007/s10633-016-9553-y CrossRefPubMedGoogle Scholar
  25. 25.
    Fahle M, Bach M (2006) Basics of the VEP. In: Heckenlively J, Arden G (eds) Principles and Practice of clinical electrophysiology of vision. MIT Press, Cambridge, London, pp 207–234Google Scholar
  26. 26.
    Bach M, Meigen T (1999) Do’s and don’ts in Fourier analysis of steady-state potentials. Doc Ophthalmol 99:69–82CrossRefPubMedGoogle Scholar
  27. 27.
    Mackay AM, Hamilton R, Bradnam MS (2003) Faster and more sensitive VEP recording in children. Doc Ophthalmol 107:251–259CrossRefPubMedGoogle Scholar
  28. 28.
    Bach M (2007) Freiburg evoked potentials. Accessed 19 Aug 2013
  29. 29.
    Wenner Y, Heinrich SP, Beisse C et al (2014) Visual evoked potential-based acuity assessment: overestimation in amblyopia. Doc Ophthalmol 128:191–200. doi: 10.1007/s10633-014-9432-3 CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Michael B. Hoffmann
    • 1
    • 2
    Email author
  • Jan Brands
    • 1
  • Wolfgang Behrens-Baumann
    • 1
  • Michael Bach
    • 3
    • 4
  1. 1.Department of OphthalmologyOtto-von-Guericke UniversityMagdeburgGermany
  2. 2.Center for Behavioural Brain SciencesMagdeburgGermany
  3. 3.Eye Center, Medical Center – University of FreiburgFreiburgGermany
  4. 4.Faculty of MedicineUniversity of FreiburgFreiburgGermany

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