Background: A 38-year-old, right-handed man with late-onset right frontal epilepsy due to a ganglioglioma and atypical right hemispheric language dominance is described.
Methods: Language dominance was investigated with functional transcranial Doppler sonography (fTCD), and language localization with functional magnetic resonance imaging (fMRI).
Results: During a word generation task, fTCD showed atypical right hemispheric language dominance, which was confirmed by fMRI using a semantic word comparison and a word stem completion task. This information helped to guide the resective procedure, which left the patient seizure-free and did not induce new deficits.
Conclusion: Functional TCD appears to be a useful and reliable screening tool for determining hemispheric language dominance, even in patients with atypical language representation. Functional MRI may be used to confirm fTCD results and further localize eloquent cortex.