title: Language outcomes after resection of dominant inferior parietal lobule gliomas.
abstract: OBJECTIVE The dominant inferior parietal lobule (IPL) contains cortical and subcortical regions essential for language. Although resection of IPL tumors could result in language deficits, little is known about the likelihood of postoperative language morbidity or the risk factors predisposing to this outcome. METHODS The authors retrospectively examined a series of patients who underwent resections of gliomas from the dominant IPL. Postoperative language outcomes were characterized across the patient population. To identify factors associated with postoperative language morbidity, the authors then compared features between those patients who experienced postoperative deficits and those who experienced no postoperative language dysfunction. RESULTS Twenty-four patients were identified for analysis. Long-term language deficits occurred in 29.2% of patients (7 of 24): 3 of these patients had experienced preoperative language deficits, whereas new long-term language deficits occurred in 4 patients (16.7%; 4 of 24). Of those patients who exhibited preoperative language deficits, 62.5% (5 of 8) experienced long-term resolution of their language deficits with surgical treatment. All patients underwent intraoperative brain mapping by direct electrical stimulation. Awake, intraoperative cortical language mapping was performed on 17 patients (70.8%). Positive cortical language sites were identified in 23.5% of these patients (4 of 17). Awake, intraoperative subcortical language mapping was performed in 8 patients (33.3%). Positive subcortical language sites were identified in 62.5% of these patients (5 of 8). Patients with positive cortical language sites exhibited a higher rate of long-term language deficits (3 of 4, 75%), compared with those who did not (1 of 13, 7.7%; p = 0.02). Although patients with positive subcortical language sites exhibited a higher rate of long-term language deficits than those who exhibited only negative sites (40.0% vs 0.0%, respectively), this difference was not statistically significant (p = 0.46). Additionally, patients with long-term language deficits were older than those without deficits (p < 0.05). CONCLUSIONS In a small number of patients with preoperative language deficits, IPL glioma resection resulted in improved language function. However, in patients with intact preoperative language function, resection of IPL gliomas may result in new language deficits, especially if the tumors are diffuse, high-grade lesions. Thus, language-dominant IPL glioma resection is not risk-free, yet it is safe and its morbidity can be reduced by the use of cortical and subcortical stimulation mapping.
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Derek G
authors.initials: DG
authors.lastname: Southwell
authors.affiliation: Università degli Studi di Milano, Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Riva
authors.affiliation: Neurology, and.|Graduate Group in Bioengineering, University of California, Berkeley and San Francisco, California; and.
authors.forename: Kesshi
authors.initials: K
authors.lastname: Jordan
authors.affiliation: Neurology, and.|Department of Brain and Behavioral Sciences, University of Pavia, Italy.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Caverzasi
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: David W
authors.initials: DW
authors.lastname: Perry
authors.affiliation: Neurology, and.|Radiology and Biomedical Imaging, University of California, San Francisco, California.|Graduate Group in Bioengineering, University of California, Berkeley and San Francisco, California; and.
authors.forename: Roland G
authors.initials: RG
authors.lastname: Henry
authors.affiliation: Departments of 1 Neurological Surgery.
authors.forename: Mitchel S
authors.initials: MS
authors.lastname: Berger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000601:surgery*; D005260:Female; D005910:Glioma / Q000601:surgery*; D006801:Humans; D007806:Language Disorders / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D018570:Risk Assessment; D016896:Treatment Outcome; D055815:Young Adult
keywords: ADP = afterdischarge potential; AF = arcuate fascicle; AG = angular gyri; DES = direct electrical stimulation; DWI = diffusion-weighted imaging; EOR = extent of resection; FLAIR = fluid-attenuated inversion recovery; GTR = gross-total resection; HARDI = high angular resolution diffusion-weighted imaging; HGG = high-grade glioma; IFOF = inferior frontooccipital fascicle; IPL = inferior parietal lobule; LGG = low-grade glioma; PR = partial resection; SLF-tp = superior longitudinal fascicle-temporoparietal portion; SMG = supramarginal gyri; STR = subtotal resection; direct electrical stimulation; extent of resection; glioma; inferior parietal lobule; language; oncology