The Neuronal Reserve Capacity Defines the Neurological Outcome in Motor-Eloquent Glioma Patients.
Shorter tumor-to-motor-tract distance is associated with greater risk of motor deficit in glioma patients.
The Neuronal Reserve Capacity Defines the Neurological Outcome in Motor-Eloquent Glioma Patients.
Glioma patients risk incurring motor deficits, which are detrimental to quality of life and survival.
We seek to characterize this capacity by distinguishing features associated with motor stability from those that signal impending impairment.
We analyzed data of 194 patients suspected of glioma who underwent preoperative nTMS motor mapping between 2015 and 2022.
shorter tumor to motor tract distance raises motor deficit risk
Female sex was protective (OR = 0.265; 95% CI, 0.089-0.785; P = .017).
In univariable analyses, elevated cortical silent period ratios correlated with poorer baseline status (OR = 3.895; 95% CI, 1.306-11.081, P = .014), while motor-impaired patients had a smaller motor volume in the lesioned hemisphere (r = 0.391; P = .022).
Hyperexcitability and inadequate neuronal recruitment in tumor-affected hemispheres indicate an unstable compensatory capacity and warn of impending motor impairment, with shorter tumor-to-tract distance also increasing risk.
Excessive GABAergic inhibition reflects neuronal reserve exhaustion, whereas shrunken motor volume may indicate failure to initiate compensatory remodeling. More robust reserve is seen in primary tumor presentations and female sex.