{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T17:55:41Z","timestamp":1777571741414,"version":"3.51.4"},"reference-count":50,"publisher":"SAGE Publications","issue":"3","license":[{"start":{"date-parts":[[2021,7,28]],"date-time":"2021-07-28T00:00:00Z","timestamp":1627430400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Clin EEG Neurosci"],"published-print":{"date-parts":[[2022,5]]},"abstract":"<jats:p>Background. Interest in electroencephalographic (EEG) coronavirus disease 2019 (COVID-19) findings has been growing, especially in the search for a specific-features EEG of encephalopathy. Methods. We made a retrospective analysis of 29 EEGs recorded in 15 patients with COVID-19 and neurological symptoms. We classified the EEGs as \u201cAcute EEG\u201d and \u201cfollow-up EEG.\u201d We did a statistical analysis between voltage and respiratory status of the patient, stay or not in the intensive care unit (ICU), days of stay in the ICU, sedative drugs, pharmacological treatment, type of symptoms predominating, and outcome. Results. We found EEG abnormalities in all patients studied. We observed the amplitude of background &lt;20\u2005\u00b5V at 93% of \u201cacute EEG,\u201d versus only 21.4% of \u201cfollow-up EEG.\u201d The average voltage went from 12.33\u2009\u00b1\u20095.09\u2005\u00b5V in the acute EEGs to 32.8\u2009\u00b1\u200920.13\u2005\u00b5V in the follow-up EEGs. A total of 60% of acute EEGs showed an intermittent focal rhythmic. We have not found a statistically significant association between voltage of acute EEG and nonneurological clinical status (including respiratory) that may interfere with the EEG findings. Conclusions. Nonspecific diffuse slowing EEG pattern in COVID-19 is the most common finding reported, but we found in addition to that, as a distinctive finding, low voltage EEG, that could explain the low prevalence of epileptic activity published in these patients. A metabolic\/hypoxic mechanism seems unlikely on the basis of our EEG findings. This pattern in other etiologies is reminiscent of severe encephalopathy states associated with poor prognosis. However, an unreactive low voltage pattern in COVID-19 patients is not necessarily related to poor prognosis.<\/jats:p>","DOI":"10.1177\/15500594211035923","type":"journal-article","created":{"date-parts":[[2021,7,28]],"date-time":"2021-07-28T11:15:44Z","timestamp":1627470944000},"page":"215-228","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":24,"title":["Retrospective Analysis of EEG in Patients With COVID-19: EEG Recording in Acute and Follow-up Phases"],"prefix":"10.1177","volume":"53","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1089-4004","authenticated-orcid":false,"given":"Isabel","family":"S\u00e1ez-Landete","sequence":"first","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4965-2707","authenticated-orcid":false,"given":"Adriana","family":"G\u00f3mez-Dom\u00ednguez","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Beatriz","family":"Estrella-Le\u00f3n","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8416-5205","authenticated-orcid":false,"given":"Alba","family":"D\u00edaz-Cid","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Olga","family":"Fedirchyk","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Escribano-Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Pedrera-Mazarro","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guillermo","family":"Mart\u00edn-Palomeque","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Hospital Universitario Ram\u00f3n y Cajal, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guillermo","family":"Garcia-Ribas","sequence":"additional","affiliation":[{"name":"Departament of Neurology. 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