• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Brain Tumors; Higher spatial resolution of fMRI is needed for neurosurgical planning

Posted on: Thursday, 4 March 2004, 06:00 CST

2004 MAR 9 - (NewsRx.com & NewsRx.net) -- Study shows that 2-mm isotropic voxels significantly enhanced the spatial localization of activation to within the gray matter.

"The unambiguous localization of eloquent functional areas is necessary to decrease the neurological morbidity of neurosurgical procedures. We explored the minimum spatial resolution requirements for functional magnetic resonance imaging (fMRI) data acquisition when brain mapping is used in neurosurgical planning and navigation," researchers in the United States report.

"Using a 1.5 Tesla clinical MRI scanner, eight patients with brain tumors underwent fMRI scans using spatial resolution of approximately 4 x 4 x 4 mm[sup]3 to map the eloquent motor and language areas during the performance of cognitive/sensorimotor tasks. The fMRl results were then used intraoperatively in an open MRI system to delineate eloquent areas," wrote S.S. Yoo and colleagues, Harvard University, Brigham & Women's Hospital.

"Retrospectively, activation patterns were visually inspected by a neurosurgeon to determine qualitatively whether ambiguity with respect to the activation boundaries, due to low spatial resolution, could be of potential significance for surgical guidance. A significant degree of ambiguity in both the extent and shape of activation was judged to be present in data from six of the eight patients," the researchers wrote.

"Analysis of fMRl data at multiple resolutions from a normal volunteer showed that at 3 mm isotropic resolution, eloquent areas were better localized within the gray matter although there was still some potential for ambiguity caused by activations appearing to cross a sulcus. The data acquired with 2-mm isotropic voxels significantly enhanced the spatial localization of activation to within the gray matter," they added.

"Thus, isotropic spatial resolution on the order of 2 x 2 x 2 mm[sup]3, which is much higher than the resolutions used in typical fMRl examinations, may be needed for the unambiguous identification of cortical activation with respect to tumors and important anatomical landmarks," the researchers concluded.

Yoo and colleagues published their study in Human Brain Mapping (Evaluating requirements for spatial resolution of fMRI for neurosurgical planning. Hum Brain Mapp, 2004;21(1):34-43).

For additional information, contact L.P. Panych, Harvard University, Brigham & Women's Hospital, School of Medicine, Department of Radiology, 75 Francis St., Boston, MA 02115, USA.

Publisher contact information for the journal Human Brain Mapping is: Wiley-Liss, Division of John Wiley & Sons Inc., 605 Third Avenue, New York, NY 10158-0012, USA.

The information in this article comes under the major subject areas of Neurosurgery, Medical Devices, and Oncology.

This article was prepared by Cancer Weekly editors from staff and other reports. Copyright 2004, Cancer Weekly via NewsRx.com & NewsRx.net.

More News in this Category