When someone has a suspected brain injury, it's not uncommon for an MRI to be ordered. When you get into MRI testing there's a number of different tests that the doctors have a choice of ordering depending on what they suspect is going on.
It is very common for a standard MRI for a brain injury to come back normal. That doesn't necessarily mean that there is no brain injury. After a normal MRI, the doctor can consider any number of more specific MRI tests to find certain areas of damage. One of the ones would be a diffusion tensor imaging MRI or DTI, sometimes called a diffusion MRI.
A diffusion MRI is designed to examine the water or fluid pathways in the white matter of the brain which are the deeper tissues of the brain. These are sort of like the connecting pathways between the areas of the brain. What happens many times is a person may have been involved in some type of an accident and they might have symptoms such as memory loss, motor coordination, word finding or whatever the symptoms may be. The doctors are looking for an explanation of what is going on. This diffusion MRI many times will reveal the damage to the neurons or axons of the brain affecting that particular part of the person's motor coordination, speech or what have you.
The diffusion tensor imaging MRI is a very important component in the process used by the physicians to identify, detect and recommend treatment for someone who has suffered a significant brain injury.