Introduction: Using mapping of the motor cortex by transcranial magnetic stimulation navigated to assess cortical plasticity and displacement motor area in patients with low-grade gliomas .
Methods: In this prospective study, six patients with low-grade gliomas in or near the precentral gyrus underwent TMS mapping, and their motor responses were correlated to locations in the cortex around the lesion, generating a functional map overlaid on three-dimensional magnetic resonance imaging (MRI) scans of the brain. To determine anatomical changes, we compared TMS mapping in each hemisphere, comparing side with tumor versus contralateral normal side
Results: Referring to the distortion of the anatomy of the motor area , we have identified differences comparing the normal side of the patients as control ( p = 0.001 ). When we analyze a comparative areas of transcranial magnetic stimulation in the side with the tumor with the normal hemisphere, we identified a smaller mapped area in the cortex with anatomical deformity compared to the area of the normal cortex ( p = 0.01 )
Conclusions: Low grade gliomas in motor area result in important cortical displacement
Patient Care: understanding the cortical changes in patients with gliomas may prevent postoperative neurological sequelae
Learning Objectives: 1. studying the physiology of the motor cortex and aspects of cortical plasticity
2. To describe aspects of neuronal recruitment in low-grade gliomas surgery
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