{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T20:27:58Z","timestamp":1787776078697,"version":"build-2784847793"},"reference-count":28,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"5","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,9]]},"abstract":"<jats:sec>\n                    <jats:title>Background and Objectives:<\/jats:title>\n                    <jats:p>Magnetoencephalography (MEG) could be a valuable tool in the presurgical evaluation of drug-resistant epilepsy (DRE), especially when the initial evaluation is inconclusive. In this retrospective study, we describe the profile of MEG in patients with DRE and normal magnetic resonance imaging (MRI).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>We included patients with focal epilepsy and normal MRI who underwent presurgical evaluation for DRE. MEG profiles of these patients, including the frequency of spikes, density of clusters, number of clusters, and concordance with video electroencephalography (VEEG), were analyzed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      Of the 73 patients included, magnetic source imaging (MSI) provided localizing information in 51 (69.9%) patients. Among patients with localizing MEG findings, localizing information on VEEG too was noted in 42 (57.5% of the whole cohort). Thirty-one (42.5%) patients had concordant findings with region-specific localization, six (8.2%) patients had partial concordance, and five (6.8%) subjects showed discordant findings. There was a moderate agreement for the presumed epileptogenic zone in comparing findings derived from MEG and VEEG (kappa value of 0.451,\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      &lt; 0.001). The agreement was lower when MEG localized to the frontal lobe (kappa value of 0.379,\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      = 0.001) than the temporal lobe (kappa value 0.442,\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      = 0.002).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>MEG can provide localizing information in most patients with a normal MRI. A moderate degree of agreement between localization by MEG and VEEG was noted. These findings highlight the usefulness of MSI in the presurgical evaluation of MRI-negative DRE.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.4103\/aian.aian_251_24","type":"journal-article","created":{"date-parts":[[2024,9,30]],"date-time":"2024-09-30T03:00:37Z","timestamp":1727665237000},"page":"500-505","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":3,"title":["Magnetoencephalography Profile of Patients with Drug-Resistant Focal Epilepsy and Normal MRI"],"prefix":"10.4103","volume":"27","author":[{"given":"Ajay","family":"Asranna","sequence":"first","affiliation":[{"name":"Department of Neurology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asheeb","family":"Abdulhak","sequence":"additional","affiliation":[{"name":"Department of Neurology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lakshminarayanapuram Gopal","family":"Viswanathan","sequence":"additional","affiliation":[{"name":"Department of Neurology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ravindranandh Chowdary","family":"Mundlamuri","sequence":"additional","affiliation":[{"name":"Department of Neurology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raghavendra","family":"Kenchaiah","sequence":"additional","affiliation":[{"name":"Department of Neurology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariyappa","family":"Narayanan","sequence":"additional","affiliation":[{"name":"Department of MEG Research Centre, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhargava","family":"Gautham","sequence":"additional","affiliation":[{"name":"Department of MEG Research Centre, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Velumurugan","family":"Jayabal","sequence":"additional","affiliation":[{"name":"Department of MEG Research Centre, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rose Dawn","family":"Bharath","sequence":"additional","affiliation":[{"name":"Department of Neuroimaging and Interventional Radiology (NIIR), NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jitender","family":"Saini","sequence":"additional","affiliation":[{"name":"Department of Neuroimaging and Interventional Radiology (NIIR), NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chandana","family":"Nagaraj","sequence":"additional","affiliation":[{"name":"Department of Neuroimaging and Interventional Radiology (NIIR), NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandhya","family":"Mangalore","sequence":"additional","affiliation":[{"name":"Department of Neuroimaging and Interventional Radiology (NIIR), NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karthik","family":"Kulanthaivelu","sequence":"additional","affiliation":[{"name":"Department of Neuroimaging and Interventional Radiology (NIIR), NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nishanth","family":"Sadashiva","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A","family":"Mahadevan","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jamuna","family":"Rajeswaran","sequence":"additional","affiliation":[{"name":"Department of Neuropsychology, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arivazhagan","family":"Arimappamagan","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhaskara Rao","family":"Malla","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, NIMHANS, Bengaluru, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sanjib","family":"Sinha","sequence":"additional","affiliation":[{"name":"Department of 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