{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T05:44:10Z","timestamp":1775713450785,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,18]],"date-time":"2022-01-18T00:00:00Z","timestamp":1642464000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["39004 and 148563"],"award-info":[{"award-number":["39004 and 148563"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Background: Epilepsy surgery failure is not uncommon, with several explanations having been proposed. In this series, we detail cases of epilepsy surgery failure subsequently attributed to insular involvement. Methods: We retrospectively identified patients investigated at the epilepsy monitoring units of two Canadian tertiary care centers (2004\u20132020). Included patients were adults who had undergone epilepsy surgeries with recurrence of seizures post-operatively and who were subsequently determined to have an insular epileptogenic focus. Clinical, electrophysiological, neuroimaging, and surgical data were synthesized. Results: We present 14 patients who demonstrated insular epileptic activity post-surgery-failure as detected by intracranial EEG, MEG, or seizure improvement after insular resection. Seven patients had manifestations evoking possible insular involvement prior to their first surgery. Most patients (8\/14) had initial surgeries targeting the temporal lobe. Seizure recurrence ranged from the immediate post-operative period to one year. The main modality used to determine insular involvement was MEG (8\/14). Nine patients underwent re-operations that included insular resection; seven achieved a favorable post-operative outcome (Engel I or II). Conclusions: Our series suggests that lowering the threshold for suspecting insular epilepsy may be necessary to improve epilepsy surgery outcomes. Detecting insular epilepsy post-surgery-failure may allow for re-operations which may lead to good outcomes.<\/jats:p>","DOI":"10.3390\/brainsci12020125","type":"journal-article","created":{"date-parts":[[2022,1,18]],"date-time":"2022-01-18T08:09:20Z","timestamp":1642493360000},"page":"125","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Insular Involvement in Cases of Epilepsy Surgery Failure"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8386-8897","authenticated-orcid":false,"given":"Jimmy","family":"Li","sequence":"first","affiliation":[{"name":"University of Montreal Health Center Research Center (CRCHUM), 900 St.-Denis Street, Montreal, QC H2X 0A9, Canada"},{"name":"Neurology Division, University of Sherbrooke Health Center (CHUS), Sherbrooke, QC J1H 5H3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sandra","family":"Reiter-Campeau","sequence":"additional","affiliation":[{"name":"Montreal Neurological Institute and Hospital (MNI\/MNH), Montreal, QC H3A 2B4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2929-2815","authenticated-orcid":false,"given":"Dina","family":"Namiranian","sequence":"additional","affiliation":[{"name":"Neurology Division, Jewish General Hospital (JGH), Montreal, QC H3T 1E2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7446-0312","authenticated-orcid":false,"given":"D\u00e8nahin Hinnoutondji","family":"Toffa","sequence":"additional","affiliation":[{"name":"University of Montreal Health Center Research Center (CRCHUM), 900 St.-Denis Street, Montreal, QC H2X 0A9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alain","family":"Bouthillier","sequence":"additional","affiliation":[{"name":"Neurosurgery Division, University of Montreal Health Center (CHUM), Montreal, QC H2X 3A4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fran\u00e7ois","family":"Dubeau","sequence":"additional","affiliation":[{"name":"Montreal Neurological Institute and Hospital (MNI\/MNH), Montreal, QC H3A 2B4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dang Khoa","family":"Nguyen","sequence":"additional","affiliation":[{"name":"University of Montreal Health Center Research Center (CRCHUM), 900 St.-Denis Street, Montreal, QC H2X 0A9, Canada"},{"name":"Neurology Division, University of Montreal Health Center (CHUM), Montreal, QC H2X 3A4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2018","DOI":"10.1093\/brain\/awh221","article-title":"Temporal lobectomy: Long-term seizure outcome, late recurrence and risks for seizure recurrence","volume":"127","author":"McIntosh","year":"2004","journal-title":"Brain J. 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