Postoperative speech disorder after medial frontal surgery: role of the supplementary motor area.
BACKGROUND
Patients undergoing surgical resection of medial frontal lesions may present transient postoperative speech disorders that remain largely unpredictable.


OBJECTIVE
To relate the occurrence of this speech deficit to the specific surgical lesion of the supplementary motor area (SMA) involved during language tasks using fMRI.


METHODS
Twelve patients were studied using a verbal fluency task before resection of a low-grade glioma of the medial frontal lobe and compared with six healthy subjects. Pre- and postoperative MR variables including the hemispheric dominance for language, the extent of SMA removal, and the volume of resection were compared to the clinical outcome.


RESULTS
Following surgery, 6 of 12 patients presented speech disorders. The deficit was similar across patients, consisting of a global reduction in spontaneous speech, ranging from a complete mutism to a less severe speech reduction, which recovered within a few weeks or months. The occurrence of the deficit was related to the resection of the activation in the SMA of the dominant hemisphere for language (p < 0.01). Increased activation in the SMA of the healthy hemisphere on the preoperative fMRI was observed in patients with postoperative speech deficit.


CONCLUSIONS
fMRI is able to identify the area at risk in the SMA, of which resection is related to the occurrence of characteristic transient postoperative speech disorders. Increased SMA activation in the healthy hemisphere suggested that a plastic change of SMA function occurred in these patients.
Krainik
A
A
Department of Neuroradiology, Hôpital de la Salpêtrière, Paris, France.
Lehéricy
S
S
Duffau
H
H
Capelle
L
L
Chainay
H
H
Cornu
P
P
Cohen
L
L
Boch
A-L
AL
Mangin
J-F
JF
Le Bihan
D
D
Marsault
C
C
D000328:Adult; D001932:Brain Neoplasms / Q000601:surgery*; D004292:Dominance, Cerebral; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D005910:Glioma / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009155:Mutism / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D009473:Neuronal Plasticity; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology*; D012016:Reference Values; D018570:Risk Assessment; D013064:Speech Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology