{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:25:02Z","timestamp":1787030702972,"version":"build-2736575974"},"reference-count":40,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T00:00:00Z","timestamp":1787011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Corticospinal tract (CST) integrity is a well-established imaging correlate of post-stroke motor outcome but does not fully explain interindividual variability, particularly in moderate-to-severe impairment. The corpus callosum (CC) may provide complementary structural information. This study examined whether early subacute callosal microstructure is associated with upper limb motor outcome and recovery.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively analyzed 38 patients with moderate-to-severe middle cerebral artery stroke who underwent diffusion tensor imaging during the early subacute phase. Fractional anisotropy (FA) values of the CST and CC were obtained. Upper limb motor function was assessed using the Shoulder Abduction and Finger Extension (SAFE) score. Simple linear regression and hierarchical multiple linear regression analyses examined associations of corrected CC FA (CC-FA\u202f~\u202fcorrected~) with SAFE scores and \u0394SAFE (change in SAFE score from baseline to 6\u202fmonths).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      CST FA laterality index (CST FALI), lesion volume, and CC-FA\u202f~\u202fcorrected~ were significantly associated with SAFE scores at 3 and 6\u202fmonths post-stroke. In hierarchical multiple regression models, CC-FA\u202f~\u202fcorrected~ of the genu showed a consistent nominal incremental contribution beyond CST FALI, age, and lesion volume at both timepoints (3\u202fmonths: \u0394R\n                      <jats:sup>2<\/jats:sup>\n                      \u202f=\u202f0.061, adjusted R\n                      <jats:sup>2<\/jats:sup>\n                      \u202f=\u202f0.600; 6\u202fmonths: \u0394R\n                      <jats:sup>2<\/jats:sup>\n                      \u202f=\u202f0.065, adjusted R\n                      <jats:sup>2<\/jats:sup>\n                      \u202f=\u202f0.646), though these findings require confirmation in larger prospective cohorts. The body and splenium did not reach statistical significance after accounting for these covariates. In exploratory analysis, CC-FA\u202f~\u202fcorrected~ of the genu was the only variable significantly associated with \u0394SAFE (R\u202f=\u202f0.396,\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.041); CST FALI was not (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.097).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>CC-FA\u202f~\u202fcorrected~ of the genu showed a consistent nominal association with upper limb motor outcome beyond CST integrity in moderate-to-severe stroke, suggesting a complementary role of callosal microstructure alongside CST integrity, with an exploratory association also observed for the magnitude of motor improvement over time. Early combined assessment of CC and CST integrity during the subacute phase may provide preliminary information regarding post-stroke motor outcomes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fneur.2026.1852619","type":"journal-article","created":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:28:31Z","timestamp":1787027311000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Association between corpus callosum microstructure and upper limb motor outcome in moderate-to-severe ischemic stroke patients at 3\u20136\u202fmonths post-stroke"],"prefix":"10.3389","volume":"17","author":[{"given":"Jaeun","family":"Koo","sequence":"first","affiliation":[{"name":"Department of Rehabilitation Medicine, Yeouido St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ah Yeon","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Seoul St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eunjoo","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Yeouido St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"So-Youn","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Yeouido St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Youngkook","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Yeouido St. Mary\u2019s Hospital, College of Medicine, The Catholic University of Korea","place":["Seoul, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,18]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"848","DOI":"10.1002\/ana.24472","article-title":"Proportional recovery after stroke depends on corticomotor integrity","volume":"78","author":"Byblow","year":"2015","journal-title":"Ann Neurol"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"826","DOI":"10.1016\/S1474-4422(17)30283-1","article-title":"Prediction of motor recovery after stroke: advances in biomarkers","volume":"16","author":"Stinear","year":"2017","journal-title":"Lancet Neurol"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"811","DOI":"10.1002\/acn3.488","article-title":"PREP2: A biomarker-based algorithm for predicting upper limb function after stroke","volume":"4","author":"Stinear","year":"2017","journal-title":"Ann Clin Transl Neurol"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"1854","DOI":"10.1161\/strokeaha.123.043109","article-title":"Accuracy of measurements of the structural reserve for upper limb function in patients with moderate-to-severe stroke","volume":"54","author":"Yoo","year":"2023","journal-title":"Stroke"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"e402","DOI":"10.1212\/WNL.0000000000200517","article-title":"Observational Study of Neuroimaging Biomarkers of Severe Upper Limb Impairment After Stroke","volume":"99","author":"Hayward","year":"2022","journal-title":"Neurology"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"2662","DOI":"10.1093\/cercor\/bhr344","article-title":"Contralesional hemisphere control of the proximal paretic upper limb following stroke","volume":"22","author":"Bradnam","year":"2012","journal-title":"Cereb Cortex"},{"key":"ref7","doi-asserted-by":"publisher","first-page":"597","DOI":"10.1038\/nrneurol.2014.162","article-title":"Modulation of brain plasticity in stroke: a novel model for neurorehabilitation","volume":"10","author":"Di Pino","year":"2014","journal-title":"Nat Rev Neurol"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"e0122615","DOI":"10.1371\/journal.pone.0122615","article-title":"The microstructural status of the corpus callosum is associated with the degree of motor function and neurological deficit in stroke patients","volume":"10","author":"Li","year":"2015","journal-title":"PLoS One"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"1959","DOI":"10.1016\/j.clinph.2014.12.018","article-title":"Diffusion imaging and transcranial magnetic stimulation assessment of transcallosal pathways in chronic stroke","volume":"126","author":"Mang","year":"2015","journal-title":"Clin Neurophysiol"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"241","DOI":"10.1161\/strokeaha.119.028832","article-title":"Multimodal assessment of the motor system in patients with chronic ischemic stroke","volume":"52","author":"Nazarova","year":"2021","journal-title":"Stroke"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"641","DOI":"10.1016\/j.nicl.2017.02.023","article-title":"Role of corpus callosum integrity in arm function differs based on motor severity after stroke","volume":"14","author":"Stewart","year":"2017","journal-title":"Neuroimage Clin"},{"key":"ref12","doi-asserted-by":"publisher","first-page":"2438","DOI":"10.1161\/STROKEAHA.123.043713","article-title":"White Matter Integrity and Chronic Poststroke Upper Limb Function: An ENIGMA Stroke Recovery Analysis","volume":"54","author":"Domin","year":"2023","journal-title":"Stroke"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"793","DOI":"10.1177\/1545968317732668","article-title":"Agreed Definitions and a Shared Vision for New Standards in Stroke Recovery Research: The Stroke Recovery and Rehabilitation Roundtable Taskforce","volume":"31","author":"Bernhardt","year":"2017","journal-title":"Neurorehabil Neural Repair"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"745","DOI":"10.1161\/STROKEAHA.109.572065","article-title":"Presence of finger extension and shoulder abduction within 72 hours after stroke predicts functional recovery: early prediction of functional outcome after stroke: the EPOS cohort study","volume":"41","author":"Nijland","year":"2010","journal-title":"Stroke"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"1228","DOI":"10.1016\/S1474-4422(10)70247-7","article-title":"Prediction of recovery of motor function after stroke","volume":"9","author":"Stinear","year":"2010","journal-title":"Lancet Neurol"},{"key":"ref16","doi-asserted-by":"publisher","first-page":"264","DOI":"10.1177\/10538135251336921","article-title":"Gait Recovery in Patients with Stroke with Severe Motor Damage: The Prognostic Role of Sensory Pathway Preservation","volume":"57","author":"Ju","year":"2025","journal-title":"NeuroRehabilitation"},{"key":"ref17","doi-asserted-by":"publisher","first-page":"2669","DOI":"10.1161\/STROKEAHA.125.050733","article-title":"Structural Brain Plasticity in Chronic Stroke: Cerebellar Remodeling and Its Association With Upper Limb Motor Outcome","volume":"56","author":"Yoo","year":"2025","journal-title":"Stroke"},{"key":"ref18","doi-asserted-by":"publisher","first-page":"554","DOI":"10.1177\/15459683231177607","article-title":"Structural Integrity of the Cerebellar Outflow Tract Predicts Long-Term Motor Function After Middle Cerebral Artery Ischemic Stroke","volume":"37","author":"Yoo","year":"2023","journal-title":"Neurorehabil Neural Repair"},{"key":"ref19","doi-asserted-by":"publisher","first-page":"989","DOI":"10.1016\/j.neuroimage.2006.05.044","article-title":"Topography of the human corpus callosum revisited\u2014Comprehensive fiber tractography using diffusion tensor magnetic resonance imaging","volume":"32","author":"Hofer","year":"2006","journal-title":"NeuroImage"},{"key":"ref20","doi-asserted-by":"publisher","first-page":"1789","DOI":"10.1111\/ejn.16005","article-title":"Evidence of lateralised white matter plasticity: A longitudinal study of balance performance in nonexpert healthy adults","volume":"57","author":"Im","year":"2023","journal-title":"Eur J Neurosci"},{"key":"ref21","doi-asserted-by":"publisher","first-page":"202","DOI":"10.1177\/15459683241309580","article-title":"Poststroke Ipsilesional Motor Performance: Microstructural Biomarkers and Their Associations With Executive Function","volume":"39","author":"Kim","year":"2025","journal-title":"Neurorehabil Neural Repair"},{"key":"ref22","doi-asserted-by":"publisher","first-page":"214","DOI":"10.3389\/fneur.2015.00214","article-title":"Role of the Contralesional Hemisphere in Post-Stroke Recovery of Upper Extremity Motor Function","volume":"6","author":"Buetefisch","year":"2015","journal-title":"Front Neurol"},{"key":"ref23","doi-asserted-by":"publisher","first-page":"158","DOI":"10.1186\/s12984-021-00947-8","article-title":"Resting motor threshold in the course of hand motor recovery after stroke: a systematic review","volume":"18","author":"Veldema","year":"2021","journal-title":"J Neuroeng Rehabil"},{"key":"ref24","doi-asserted-by":"publisher","first-page":"50","DOI":"10.31083\/j.jin2102050","article-title":"Effects of corticospinal tract integrity on upper limb motor function recovery in stroke patients treated with repetitive transcranial magnetic stimulation","volume":"21","author":"Wang","year":"2022","journal-title":"J Integr Neurosci"},{"key":"ref25","doi-asserted-by":"publisher","first-page":"51","DOI":"10.3233\/NRE-141191","article-title":"Long-term effects of contralesional rTMS in severe stroke: safety, cortical excitability, and relationship with transcallosal motor fibers","volume":"36","author":"Demirtas-Tatlidede","year":"2015","journal-title":"NeuroRehabilitation"},{"key":"ref26","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1155\/2017\/4281532","article-title":"Interhemispheric Pathways Are Important for Motor Outcome in Individuals with Chronic and Severe Upper Limb Impairment Post Stroke","volume":"2017","author":"Hayward","year":"2017","journal-title":"Neural Plast"},{"key":"ref27","doi-asserted-by":"publisher","first-page":"105","DOI":"10.3389\/fneur.2019.00105","article-title":"Prefrontal-Premotor Pathways and Motor Output in Well-Recovered Stroke Patients","volume":"10","author":"Schulz","year":"2019","journal-title":"Front Neurol"},{"key":"ref28","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1093\/cercor\/4.2.166","article-title":"Multiple corticospinal neuron populations in the macaque monkey are specified by their unique cortical origins, spinal terminations, and connections","volume":"4","author":"Galea","year":"1994","journal-title":"Cereb Cortex"},{"key":"ref29","doi-asserted-by":"publisher","first-page":"1844","DOI":"10.1093\/brain\/awl106","article-title":"Non-invasive mapping of corticofugal fibres from multiple motor areas\u2014relevance to stroke recovery","volume":"129","author":"Newton","year":"2006","journal-title":"Brain"},{"key":"ref30","doi-asserted-by":"publisher","first-page":"173","DOI":"10.1016\/j.ijpsycho.2006.03.011","article-title":"Increased cognitive load during simple and complex motor tasks in acute stage after stroke","volume":"63","author":"Puh","year":"2007","journal-title":"Int J Psychophysiol"},{"key":"ref31","doi-asserted-by":"publisher","first-page":"604","DOI":"10.1002\/ana.21810","article-title":"Motor imagery after stroke: relating outcome to motor network connectivity","volume":"66","author":"Sharma","year":"2009","journal-title":"Ann Neurol"},{"key":"ref32","doi-asserted-by":"publisher","first-page":"270","DOI":"10.1002\/hbm.24793","article-title":"The importance of different learning stages for motor sequence learning after stroke","volume":"41","author":"Dahms","year":"2020","journal-title":"Hum Brain Mapp"},{"key":"ref33","doi-asserted-by":"publisher","first-page":"290","DOI":"10.1002\/hbm.21019","article-title":"Implicit sequence-specific motor learning after subcortical stroke is associated with increased prefrontal brain activations: an fMRI study","volume":"32","author":"Meehan","year":"2011","journal-title":"Hum Brain Mapp"},{"key":"ref34","doi-asserted-by":"publisher","first-page":"321","DOI":"10.1016\/j.jalz.2014.06.011","article-title":"Tract-specific white matter degeneration in aging: the Rotterdam Study","volume":"11","author":"De Groot","year":"2015","journal-title":"Alzheimers Dement"},{"key":"ref35","doi-asserted-by":"publisher","first-page":"5315","DOI":"10.1002\/hbm.24774","article-title":"Joint contributions of cortical morphometry and white matter microstructure in healthy brain aging: A partial least squares correlation analysis","volume":"40","author":"Hoagey","year":"2019","journal-title":"Hum Brain Mapp"},{"key":"ref36","doi-asserted-by":"publisher","first-page":"628865","DOI":"10.3389\/fnagi.2021.628865","article-title":"Tract Specificity of Age Effects on Diffusion Tensor Imaging Measures of White Matter Health","volume":"13","author":"Matijevic","year":"2021","journal-title":"Front Aging Neurosci"},{"key":"ref37","doi-asserted-by":"publisher","first-page":"1330","DOI":"10.1093\/cercor\/bhz169","article-title":"The Influence of Cortico-Cerebellar Structural Connectivity on Cortical Excitability in Chronic Stroke","volume":"30","author":"Guder","year":"2020","journal-title":"Cereb Cortex"},{"key":"ref38","doi-asserted-by":"publisher","first-page":"2445","DOI":"10.1016\/j.jstrokecerebrovasdis.2018.04.039","article-title":"Modification of Cerebellar Afferent Pathway in the Subacute Phase of Stroke","volume":"27","author":"Kim","year":"2018","journal-title":"J Stroke Cerebrovasc Dis"},{"key":"ref39","doi-asserted-by":"publisher","first-page":"2805","DOI":"10.1161\/strokeaha.117.016834","article-title":"Interactions between the corticospinal tract and premotor-motor pathways for residual motor output after stroke","volume":"48","author":"Schulz","year":"2017","journal-title":"Stroke"},{"key":"ref40","doi-asserted-by":"publisher","first-page":"2527","DOI":"10.1093\/brain\/aws146","article-title":"The PREP algorithm predicts potential for upper limb recovery after stroke","volume":"135","author":"Stinear","year":"2012","journal-title":"Brain"}],"container-title":["Frontiers in Neurology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fneur.2026.1852619\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:28:33Z","timestamp":1787027313000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fneur.2026.1852619\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,18]]},"references-count":40,"alternative-id":["10.3389\/fneur.2026.1852619"],"URL":"https:\/\/doi.org\/10.3389\/fneur.2026.1852619","relation":{},"ISSN":["1664-2295"],"issn-type":[{"value":"1664-2295","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,18]]},"article-number":"1852619"}}