Determination of Hemispheric Language Dominance: A Comparison between Functional Transcranial Doppler Ultrasonography (fTCD) and Wada Test.
Abstract number :
3.073
Submission category :
Year :
2001
Submission ID :
175
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
S. Knake, MD, Neurology, Philipps-University, Marburg, Germany; H.M. Hamer, MD, Neurology, Philipps-University, Marburg, Germany; J-P. Wakat, MD, Neuroradiology, Philipps-University, Marburg, Germany; C. Dittmer, Neurology, Philipps-University, Marburg, G
RATIONALE: fTCD measures event-related changes of cerebral perfusional blood flow velocity in each hemisphere. In this study we determined the language dominance in patients who underwent epilepsy surgery with fTCD and Wada test. To study the validity of fTCD-results, we compared fTCD with the Wada test.
METHODS: Wada test and fTCD were performed in 16 patients during the presurgical work-up. fTCD measured continuously blood flow velocities in both middle cerebral arteries (as previously described by Knecht et al (1)), while the patient was given a cued word generation task.
RESULTS: During Wada-testing, 14 of 16 patients showed a left hemispheric language dominance. One patient was classified as right hemispheric dominant and one patient showed bilateral representation of language function. Due to a lack of acoustic temporal bone window, fTCD could not be performed in 2 patients. In all of the 14 other patients language dominance found with fTCD was concordant with the results of the Wada test. The correlation of both laterality indices (LI) was significant (r=.716, p=0,033).
CONCLUSIONS: fTCD is a reliable, easy to use, unexpensive and fast method to determine the language lateralization non-invasively. Due to the simple task used, it is easy to apply even in children or people with low IQ. The strong correlation shows that fTCD may substitute the Wada test in future for the determination of language lateralization.
LITERATURE:
1. Knecht et al. Noninvasive Determination of Language Lateralization by Functional Transcranial Doppler Sonography. A Comparison with the Wada test. Stroke 1998;29:82-86
Wada test. Neurology 1996;49:978-84
2. Deppe et al. Average: a Windows program for automated analysis of event related cerebral blood flow. J Neurosci Methods. 1997;75:147-154[figure]