{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T11:55:07Z","timestamp":1781870107467,"version":"3.54.5"},"reference-count":26,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Childs Nerv Syst"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>Hemispherotomy is an established treatment for children with drug-resistant epilepsy. Recent reports have suggested a superiority of outcomes with the vertical approach compared to the traditional lateral approach. This study investigated whether an experienced epilepsy surgeon can safely transition from lateral peri-Sylvian to vertical parasagittal hemispherotomy, through evaluation of postoperative seizure freedom and associated outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Thirty-six patients who underwent hemispherotomy by a single surgeon between 2016 and 2025 were analysed, 23 lateral peri-Sylvian and 13 vertical parasagittal. Pre-, peri- and postoperative findings were compared across the two techniques, with Pearson\u2019s chi-squared, Fisher\u2019s exact and Mann-Whitney\n                      <jats:italic>U<\/jats:italic>\n                      tests utilised where appropriate to detect significant differences. Patients with 1-year postoperative follow-up were split into chronological epochs. A binary logistic regression model compared seizure freedom by epoch whilst controlling for factors shown to predict seizure freedom.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      90.9% of the lateral group and 83.3% of the vertical group were seizure free (Engel class I) at 1-year postoperative follow-up (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.602), with no statistically significant differences in the complication rates. Mean operative duration was significantly less for the vertical compared to the lateral group (340.9 vs 448.8\u00a0min,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.002), as was intraoperative haemoglobin drop (18.1 vs 27.2\u00a0g\/L,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.002). Mean hospital stay was comparable (8.7 vs 9.8\u00a0days,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.871). There was no statistically significant difference in 1-year seizure freedom rate noted by chronological epoch whilst adjusting for factors predicting seizure freedom (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.816).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This study demonstrates that a single experienced epilepsy surgeon can safely transition between techniques, without compromising on seizure freedom outcomes or incurring additional morbidity. Whilst larger studies may demonstrate the favourability of one technique over the other, it may be useful to the individual surgeon to have a sound grasp of both techniques in their armamentarium.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00381-026-07353-2","type":"journal-article","created":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T11:43:13Z","timestamp":1781869393000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["\u2018To improve is to change\u2019\u2014but is it safe? A single surgeon\u2019s transition from lateral to vertical hemispherotomy"],"prefix":"10.1007","volume":"42","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1176-4423","authenticated-orcid":false,"given":"Omar","family":"Salim","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0053-147X","authenticated-orcid":false,"given":"Aswin","family":"Chari","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9797-3770","authenticated-orcid":false,"given":"M. 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We confirm that we have read the Journal\u2019s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"The study was approved as a service evaluation at our institution (ID: 4468), and individual patient consent was waived.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent to participate"}},{"value":"None of the authors has any conflict of interest to disclose.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"Data partly presented as a poster presentation at the International Society of Pediatric Neurosurgery 2024 Meeting, Toronto, Canada, October 2024.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conference presentations"}}],"article-number":"257"}}