Table 1

Clinical, radiological, and surgical characteristics of the 77 patients (37 males, 40 females; mean age 37 years) with resection in a glioma in secondary and/or primary functional brain areas

Glioma locationNumber of casesPresenting symptomsClinical examinationCortico-subcortical functional boundaries identified by intraoperative stimulationsClinical resultsQuality of resection
Supplementary motor area31SeizuresNormal except mild dysphasia in 2 left gliomasPosteriorly: primary motor cortex and pyramidal pathways Laterally: language structures (left gliomas)31 immediate post-operative SMA syndromes, with recovery within 1–3 months 1 residual right lower limb monoparesia Improvements of the 2 preoperative dysphasias31 (sub) total
    Right9
    Left22
Insular lobe28SeizuresNormal except mild dysphasia in 1 left gliomaInsular cortex: language areas (left gliomas) Deeply: internal capsule (in all cases) and language pathways (left gliomas)20 immediate motor deficits and 7 mild speech disturbances (left gliomas) Recovery within 3 months except 3 residual hemiparesia Improvement of the preoperative dysphasia22 (sub) total
    Right206 partial (left gliomas)
    Left8
Primary somatosensory area8SeizuresNormalAnteriorly: primary motor cortex and pyramidal pathways8 severe immediate sensory loss, with recovery within 3 months 2 mild residual dysesthesias8 (sub) total
    Right5
    Left3
Primary motor area4SeizuresNormalFace area resection: primary motor cortex and pyramidal pathways of the upper limb (lateral limb)    3 immediate central facial palsies and 1 hypophonia, with recovery within 1 month4 total
    Facial3
    Upper limb1“Upper limb area” resection, after functional reorganisation (second surgery): all motor sites around the “silent” region (while “eloquent” 2 years before)Immediate right upper limb after resection of the “upper limb area” with recovery within 2 weeks
Broca’s area4SeizuresNormalAll language structures around the glioma: posteriorly, within precentral gyrus; medially, within middle frontal gyrus4 immediate slight speech disturbances, with recovery within 1 week4 total
Left temporal language area2SeizuresNormal“Language area” resection, after functional reorganisation (second surgery): all language sites were behind the invaded “silent” region (while “eloquent” several months before)2 immediate dysphasias, with recovery within 3 months2 total