fMRI Technology Makes Brain Tumor Surgery Safer

The Cincinnati group is among the first in the United States to use new technology that integrates fMRI data into high-tech surgical navigation systems. The fMRI data, which target language, cognition, and mobility centers of the brain, allow neurosurgeons to remove tumors to the greatest degree possible without harming areas that are critical to the patient's quality of life.

Functional MRI creates a series of images that capture blood oxygen levels in parts of the brain that are responsible for movement, perception, and cognition. fMRI, which reveals the brain in action, is different from conventional MRI, which provides a static image. "This is a quantum leap in what we're able to do,” said Dr. James Leach, a brain-imaging specialist with UC Radiology and the Neuroscience Institute.

The fMRI technology, called the iPlan BOLD (blood oxygen level-dependent) MRI mapping, was developed by BrainLab (Munich, Germany; www.brainlab.com). It has been used successfully in 12 surgical cases so far at the University Hospital.

Tumor boundaries are not always clear, and the growth of a tumor can cause functional areas to shift from their original locations. Large tumors can cause these critical regions to shift dramatically. To identify functional areas of the brain that should not be harmed, neurosurgeons traditionally have applied a small electrical stimulation with a wand-like instrument during surgery. If a motor area is stimulated, for example, the patient's hand will move. Electrical stimulation has had drawbacks, however.

The need for electrical stimulation also can lengthen a surgical procedure by 30 to 60 minutes. While neurosurgeons make the transition to the fMRI-assisted navigation technology, they are continuing to perform brain stimulation to double-check for accuracy. Up to now, according to Dr. McPherson, the double checks have confirmed the technology's accuracy while suggesting that the technology may make brain stimulation unnecessary for many surgeries in the future.

The new BrainLab equipment also enables physicians to integrate diffusion tensor imaging (DTI), which provides a map of crucial white-matter tracts in the brain. "White-matter tracts,” said Dr. Leach, "are like the electrical connections between different parts of a house. If you disrupt that connection, you have no communication between those two areas.”


Related Links:
University of Cincinnati
BrainLab