Roles of the Wada Test and Functional Magnetic Resonance Imaging in Identifying the Language-dominant Hemisphere among Patients with Gliomas Located near Speech Areas

Neurol Med Chir (Tokyo). 2017 Jan 15;57(1):28-34. doi: 10.2176/nmc.oa.2016-0042. Epub 2016 Dec 15.

Abstract

This study examined the accuracy of functional magnetic resonance imaging (fMRI) in identifying the language-dominant hemisphere and the situations in which the Wada test can be skipped among patients with gliomas located near speech areas. We examined 74 patients [48 men (64.9%); mean ± standard deviation age of 42.7 ± 13.6 years (range: 13 to 70 years); 71 right-handed, 2 left-handed, and 1 ambidextrous] with gliomas located near speech areas. All patients underwent the Wada test and fMRI, and 34 patients underwent awake surgery. The "last-and-first" task was administered during fMRI. The Wada test was successful in determining the language-dominant hemisphere in 73 patients (98.6%): left hemisphere in 68 patients (91.9%), right hemisphere in 4 patients (5.4%), and bilateral in 1 patient (1.4%). The dominant hemisphere for right-handed patients (n = 71) was the left hemisphere in 67 patients (94.3%), right hemisphere in 3 patients (4.2%), and undetectable in 1 patient (1.4%). The fMRI was successful in determining the language-dominant hemisphere in 53 patients (71.6%). The results of the Wada test and fMRI were inconsistent in 5 patients (8.6%), of which 3 (5.2%) exhibited dominance in opposite hemispheres. Furthermore, 2 of these 3 cases (2.7%) were contralateral false positive cases, whereby fMRI identified the right-hemisphere as language dominant for right-handed individuals with tumors in the left hemisphere. Based on these findings, we concluded that the Wada test can be skipped if language dominancy can be detected by fMRI.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Brain Mapping
  • Brain Neoplasms / diagnostic imaging*
  • Brain Neoplasms / physiopathology*
  • Female
  • Functional Laterality
  • Glioma / diagnostic imaging*
  • Glioma / physiopathology*
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Retrospective Studies
  • Speech / physiology
  • Young Adult