New Brain Imaging Reveals Damage MRI Misses

Feb. 17, 2006 — -- When you look at the pictures of a brain from a typical MRI, it looks like an indistinguished blob. But the latest, cutting-edge technology called diffusion tensor imaging reveals the true wonders of the brain by developing the images into what looks like bundles of colorful wires -- thousands of them -- linking the brain's different parts. And to the patient, getting a DTI feels no different than getting an MRI.

The new imaging technology is only present in a few dozen research hospitals and not yet available to the average patient. But it already has far-reaching implications for those with head injuries because it can detect abnormalities that an MRI can't. Doctors will also be able to see more precisely how different drugs act on the brain and will be able to evaluate better the risks of brain surgery.

Of course, the brain itself is gray and white and not all of these fancy colors. If you go back to high school biology, you'll remember that the gray areas are where the processing takes place and the white matter is the connective channels that allow water to flow between various parts of the brain, making them work in coordination.

"If the white matter is normal, you're going to see it move in a direction," said Dr. Robert Zimmerman, a neuroimaging expert at Weill Medical College of Cornell University. "If the white matter is damaged, the water movement becomes chaotic."

If there is an interruption of this water movement, you're getting some impairment of brain function. By looking at where the bundles or connectors disappear, doctors can get some idea of what the effects of brain injury or disease will be.

Zimmerman said he had been looking at professional boxers and those with minor head trauma. The DTI revealed damage to one boxer's corpus callosum, which looked fine in an MRI, by showing that the "colorful wires" looked pale and thin.

"With the regular MRI, the brain looks normal. And yet, look at how, how you just don't see this structure anymore," he said when looking at the DTI. "This is all disarrayed. So, this, the motion of water through this patient's corpus callosum is disturbed. And therefore we know this patient has had damage to the structure."