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QmfrVEPs were measured monocularly in 5 normal subjects and in 5 glaucoma patients who showed losses in conventional Octopus perimetry. The pattern reversal frequency varied slightly between the stimulators: (11.92, 12.00, 12.08 and 12.16 reversals\/sec). The responses to the different stimuli were identified by discrete Fourier analysis. VEPs were recorded using different electrode configurations, and the recording with the highest signal-to-noise ratio (SNR) was used for further analysis.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>QmfrVEP responses from the different quadrants can be reliably measured and separated using the 0.08 reversals\/sec interstimulus reversal frequency differences. The signal-to-noise ratio in the four quadrants was significantly correlated with the equivalent visual field losses obtained with perimetry (Spearman rank correlation: <jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001). In the five glaucoma patients, the SNR was reduced in 15 out of the 16 quadrants with a perimetric defect, in comparison to the results in quadrants of healthy subjects. This confirms the sensitivity of the procedure.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>QmfrVEP responses can be measured reliably. This pilot study suggests that high SNR values exclude visual field defects and that focal defects can be identified in glaucoma patients.\n<\/jats:p>\n                <jats:p><jats:italic>Trial registration<\/jats:italic>: <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"http:\/\/www.clinicaltrials.gov\">www.clinicaltrials.gov<\/jats:ext-link>. NCT00494923.\n<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s10633-023-09949-4","type":"journal-article","created":{"date-parts":[[2023,9,26]],"date-time":"2023-09-26T03:29:08Z","timestamp":1695698948000},"page":"15-24","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Objective detection of visual field defects with multifrequency VEPs"],"prefix":"10.1007","volume":"148","author":[{"given":"Katja","family":"Crux","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0408-8981","authenticated-orcid":false,"given":"Cord","family":"Huchzermeyer","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9293-7380","authenticated-orcid":false,"given":"Jan","family":"Kremers","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2590-1169","authenticated-orcid":false,"given":"Folkert K.","family":"Horn","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2023,9,26]]},"reference":[{"key":"9949_CR1","doi-asserted-by":"publisher","first-page":"45847","DOI":"10.1038\/srep45847","volume":"7","author":"F Sabeti","year":"2017","unstructured":"Sabeti F, James AC, Carle CF, Essex RW, Bell A, Maddess T (2017) Comparing multifocal pupillographic objective perimetry (mfPOP) and multifocal visual evoked potentials (mfVEP) in retinal diseases. 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The authors have no commercial interest in the equipment used in this work.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"The study was approved by the ethics committee of the Friedrich-Alexander-University of Erlangen-N\u00fcrnberg and complies with the tenets of the Declaration of Helsinki.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"Informed consent was obtained from all subjects in the study, including the consent to publish the data in a journal.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent to participate"}},{"value":"See above.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The study was approved by the ethics committee of the Friedrich-Alexander-University of Erlangen-N\u00fcrnberg and complies with the tenets of the Declaration of Helsinki.","order":6,"name":"Ethics","group":{"name":"EthicsHeading","label":"Statement of human rights"}},{"value":"Not applicable.","order":7,"name":"Ethics","group":{"name":"EthicsHeading","label":"Statement on the welfare of animals"}},{"value":"Informed consent was obtained from all subjects in the study.","order":8,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}}]}}