Functional Magnetic Resonance Imaging Of The Brain

Functional magnetic resonance imaging (fMRI) is a noninvasive method for localizing areas of brain function and has been used for the presurgical evaluation of eloquent brain areas. Using this method, images are collected while specific activities are performed to assist in the localization of critical cortical areas, as well as the evaluation of language lateralization. Functional MRI is also being investigated in combination with diffusion tensor imaging and electroencephalography to identify seizure focus. For individuals who have epilepsy or brain tumors who are undergoing presurgical mapping of the eloquent cortex who receive fMRI, the evidence includes studies on diagnostic accuracy and clinical utility. The relevant outcomes are test accuracy, morbid events, functional outcomes, and quality of life. The diagnostic accuracy of fMRI has been compared with the Wada test and intracortical mapping to evaluate postoperative language changes. Sensitivity and specificity depend on the specific task but have been shown to be predictive of hemispheric dominance in a substantial percentage of patients. According to findings from health outcomes, fMRI has several benefits for patients who are to undergo neurosurgery for seizures or brain tumors; these benefits are the potential to define eloquent areas (eg, controlling verbal or motor function), and the ability to reduce surgery time and alter treatment decisions. Because of the highly detrimental impact of resecting the eloquent cortex, fMRI may be considered complementary to the Wada test and direct electrical stimulation when the lesion is in close proximity to an eloquent area of the brain. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome. For individuals who have epilepsy who are being evaluated for localization of seizure focus who receive simultaneous electroencephalography and fMRI, the evidence includes a limited number of small studies. The relevant outcomes are test accuracy, morbid events, functional outcomes, and quality of life. The objective of current research is to improve the identification of seizure focus with this technique, particularly when there are no interictal epileptic discharges during an fMRI session. There are very few data on the effect of this procedure on health outcomes. The evidence is insufficient to determine the effects of the technology on health outcomes. Additional Information Not applicable.