Postoperative reorganization of the supplementary motor area complex: A possible latent bihemispheric network

• Published in: Clinical neurology and neurosurgery 2024-11, Vol.246, p.108586, Article 108586
• Main Authors: Jiménez de la Peña, María del Mar, Gil-Robles, Santiago, Aracil, Cristina, Casado, Elena Almagro, Rubio Alonso, Margarita, Martínez de Vega, Vicente
• Format: Article
• Language: English
• Subjects: Brain cancer; Brain tumors; DIABLO protein; Frontal aslant tract: Functional expressive language; Frontal gyrus; Functional magnetic resonance imaging; Functional plasticity; Glioma; Handedness; Language; Magnetic resonance imaging; Neuroimaging; Neurological diseases; Neuroplasticity; Neurosurgery; Patients; Pre-supplementary motor area; Recovery of function; Software; Supplementary motor area; Surgery; Tumors
• ISSN: 0303-8467; 1872-6968; 1872-6968
• DOI: 10.1016/j.clineuro.2024.108586

Brain plasticity after multistep surgery in low-grade glioma is highly variable; the neurosurgical approach must be individualised and functional imaging can be used for this purpose. In supplementary motor area complex (SMAC) tumors, the early and adequate functional recovery of patients raises the possibility of a latent bihemispheric or “mirror” cortico-subcortical network, which would develop depending on the needs of each patient. Functional and DTI-MR data from 4 right-handed patients with left frontal low grade gliomas near the SMAC, who were operated at least in two occasions were collected. The time of the reintervention was variable (18 months- 8 years), related to the tumor growth. All patients were evaluated by a neuropsychologist and imaged before each surgery, in a 3 T MR, with a 24 multichanel head coil Motor and expressive language task-fMRI and DTI sequences were obtained to evidence the main cortico-subcortical components of the SMAC. Data were processed with Brainwave (GE Medical Systems) and with an Iplan Fiber Tracking tool (MEDTRONIC), respectively None of our patients presented permanent neurological deficits after the first or second functional surgery. Three patients with partial or complete resection of the left middle and / or inferior frontal gyrus, and the left frontal aslant tract evidenced new right hemispherical cortical activity. This right shift were not observed in the patient without left middle gyrus resection, indeed with partial absent of the left frontal aslant tract. SMAC is a latent cortico-subcortical bihemispheric network that allows it to reorganize itself in response to specific neurological deficits. We highlight the importance in the cortical reorganization of the left middle frontal gyrus in the SMAC, closely connected with the essential language areas of this region, but also we focused in the potential cortioco-subcortical changes to compensate the functionality of the FAT. •Authors propose a new concept of reorganization of the frontal areas involved in expressive language.•Authors manifest the importance of the combination of advanced neurofunctional imaging with the awake surgery in low-grade gliomas.•Authors highlight the relevance in the language expressive network of the left medial frontal gyrus.