Motor Functional Reorganization Is Triggered by Tumor Infiltration Into the Primary Motor Area and Repeated Surgery

Abstract

In patients with gliomas, motor deficits are not always observed, even though tumor cells infiltrate into the motor area. Currently, it is recognized that this phenomenon can occur through the neuroplasticity potential. The aim of this study is to investigate the characteristics of motor functional reorganization in gliomas. Out of 100 consecutive patients who underwent awake surgery, 29 patients were assessed as regards their motor function and were retrospectively explored to determine whether positive motor responses were elicited. A total of 73 positive mapping sites from 27 cases were identified, and their spatial anatomical locations and activated region by functional MRI were analyzed. Additionally, the factors promoting neuroplasticity were analyzed through multiple logistic regression analysis. As a result, a total of 60 points (21 cases) were found in place, while 13 points (17.8%) were found to be shifted from anatomical localization. Reorganizations were classified into three categories: Type 1 (move to ipsilateral different gyrus) was detected at nine points (four cases), and they moved into the postcentral gyrus. Type 2 (move within the ipsilateral precentral gyrus) was detected at four points (two cases). Unknown type (two cases) was categorized as those whose motor functional cortex was moved to other regions, although we could not find the compensated motor area. Two factors for the onset of reorganization were identified: tumor cells infiltrate into the primary motor area and repeated surgery (p < 0.0001 and p = 0.0070, respectively). Our study demonstrated that compensation can occur mainly in two ways, and it promoted repeated surgery and infiltration of tumor into the primary motor area.

Preserving Right Pre-motor and Posterior Prefrontal Cortices Contribute to Maintaining Overall Basic Emotion

“…Moreover, it is unclear whether the same results can be obtained in the normal brain since slow-growing gliomas might lead to reorganization with the functional shift from original localization at the cortical level (Duffau, 2014 ). Although cortical reorganization for language and motor function in gliomas has been reported (Saito et al, 2016 ; Southwell et al, 2016 ; Nakajima et al, 2020 ), brain plasticity regarding higher brain function, such as basic emotion, is poorly understood. In support of our results, some previous reports revealed that the premotor and posterior parts of the prefrontal cortices are related to basic emotion in the normal brain (Diano et al, 2017 ; Uono et al, 2017 ).…”

“…First, the positive mapping sites were plotted on the corresponding original 3DT1-images for each patient using iPlan Stereotaxy 3.0 software (BrainLab), according to operative reports and intraoperative video records. The exact locations of the DES points were determined by considering their spatial relationships to various anatomical landmarks (the gyri, sulci, vessel, and midline), as previously described (Tate et al, 2014 ; Nakajima et al, 2020 ). Next, each positive mapping site of emotion recognition on the original MR images was transferred to normalized T1-images.…”

Neural Regulation of Cancer: Cancer‐Induced Remodeling of the Central Nervous System

“…[51] Further evidence of plasticity of the motor cortical network came from patients with primary motor cortex tumors. [52] Using intraoperative stimulation mapping, Duffau and colleagues described functional reshaping of motor areas that occurred in the interval between two consecutive surgeries in a patient with left precentral WHO grade 2 oligodendroglioma. [37] Although the patient exhibited no motor neurological impairments, intraoperative electrical stimulation showed motor function within the tumor, which resulted in incomplete tumor resection during the first surgery.…”

Two Different Subcortical Networks of Language System: Morphogram and Phonogram, Through the Analysis of Unique Japanese Characters

“…The procedure for identi cation of overlapping positive mapping points was the same as that described in previous reports (Nakajima et al 2020a). First, subcortical positive mapping points were plotted on postoperative 3D T1 MR images while referring to the operative ndings and intraoperative records with iPlan Cranial 3.0 software (BrainLab).…”