{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T23:49:32Z","timestamp":1791589772262,"version":"4.3.4"},"reference-count":29,"publisher":"Georg Thieme Verlag KG","issue":"04","license":[{"start":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T00:00:00Z","timestamp":1778025600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Asian J Neurosurg"],"published-print":{"date-parts":[[2026,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Nonlesional extratemporal lobe epilepsy (ETE) remains one of the most challenging forms of drug-resistant epilepsy to treat surgically because seizure onset zones are often poorly defined on conventional neuroimaging. The long-term effectiveness of subdural grid-guided surgery in this population remains incompletely understood. This study aimed to evaluate long-term surgical outcomes in patients with intractable nonlesional extratemporal epilepsy who underwent subdural grid-guided epilepsy surgery.<\/jats:p>\n                  <jats:p>A retrospective study was conducted from January 1, 2014 to December 31, 2024. Clinical, pathological, and invasive electroencephalography data were reviewed. Seizure outcomes were assessed using Engel's classification at 6 months and 2 years after surgery.<\/jats:p>\n                  <jats:p>Fifty-five patients with nonlesional extratemporal epilepsy were included. Seizure freedom (Engel class I) was achieved in 12 patients (21.8%) at 6 months and increased to 30 patients (54.5%) at 2 years. These improvements were not statistically significant (p\u2009=\u20090.16 and 0.53, respectively). Favorable trends toward better seizure outcomes were observed in patients aged from adolescence to middle adulthood, those with tumor pathology, and those with parietal lobe seizure foci.<\/jats:p>\n                  <jats:p>Subdural grid-guided surgery for nonlesional extratemporal epilepsy resulted in seizure-free rates of 21.8% at 6 months and 54.5% at 2 years, with improvement over time but without statistically significant predictors of outcome.<\/jats:p>","DOI":"10.1055\/s-0046-1822648","type":"journal-article","created":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T22:43:37Z","timestamp":1778107417000},"page":"785-795","source":"Crossref","is-referenced-by-count":0,"title":["Long-Term Outcomes of Nonlesional Extratemporal Epilepsy Surgery Using Subdural Grid Implantation"],"prefix":"10.1055","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3989-1301","authenticated-orcid":false,"given":"Panu","family":"Boontoterm","sequence":"additional","affiliation":[{"name":"Neurological Surgery Unit, Department of Surgery, Phramongkutklao Hospital, Bangkok, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siraruj","family":"Sakoolnamarka","sequence":"additional","affiliation":[{"name":"Neurological Surgery Unit, Department of Surgery, Phramongkutklao Hospital, Bangkok, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2679-3419","authenticated-orcid":false,"given":"Karanarak","family":"Urasyanandana","sequence":"additional","affiliation":[{"name":"Neurological Surgery Unit, Department of Surgery, Phramongkutklao Hospital, Bangkok, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2026,5,6]]},"reference":[{"key":"ref1","first-page":"514","article-title":"Surgical treatment of the epilepsies: presurgical evaluation","volume":"38","author":"J Engel Jr","year":"1992","journal-title":"Clin Neurosurg"},{"issue":"01","key":"ref2","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/S1474-4422(25)00380-1","article-title":"Emerging technologies and strategies in epilepsy surgery: toward personalised medicine","volume":"25","author":"R Yardi","year":"2026","journal-title":"Lancet Neurol"},{"issue":"04","key":"ref3","doi-asserted-by":"crossref","first-page":"1009","DOI":"10.1002\/epi4.70062","article-title":"The landscape of epilepsy surgery in older adults: challenges and opportunities","volume":"10","author":"V Punia","year":"2025","journal-title":"Epilepsia Open"},{"issue":"07","key":"ref4","first-page":"CD010541","article-title":"Surgery for 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