Imaging to Help Detect Traumatic Brain Injury
The following imaging techniques can help detect traumatic brain injury:
- CT Scan - Computed Tomography is a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce slices of the brain. In CT scans the x-ray beam moves in a circle around the head. This allows many different views of the brain. The x-ray information is sent to a computer that interprets the x-ray data and displays it in two dimensional form. CT scans can show injuries to brain structure and brain tissue.
- MRI - Magnetic Resonance Imaging of the brain is a test that uses a magnetic field and pulses of radio wave energy to take pictures of the head and brain. The MRI can show damage to brain tissue and inflammation to brain tissue.
- fMRI - Functional Magnetic Resonance Imaging is an MRI that focuses on function. Using an MRI scanner, the flow of blood to different regions of the brain and shows changes in blood oxygenation and flow. When a brain is more active it consumes more oxygen causing increased blood flow to that area of the brain. An fMRI can depict abnormal brain function.
- DWI - Diffusion Weighted Imaging is a form of MRI based upon the diffusion of water molecules inside brain tissue. DWI can show brain abnormalities.
- DTI - Diffusion Tensor Imaging is a type of MRI allowing the study of brain tissue microstructure. It gives indications about possible nerve fiber anomalies in white matter in the brain that are not visible in other types of imaging. DTI can show injuries in the white matter of the brain depicting diffuse axonal injury (damage to the axons that connect the neurons - brain cells).
- SWI - Susceptibility Weighted Imaging - Originally called bold venographic imaging, uses a contrast in MRI to show the susceptibility differences between tissues. Its sensitivity to venous blood is why it is used in detecting traumatic brain injury.
- PET Scan - Positron Emission Tomography is a brain scan that is a type of imaging to test the brain. It uses a radioactive substance called a tracer to look for injury in the brain. A PET scan shows how the brain and its tissues are working and shows abnormalities.
- SPECT Scan - Single Photon Emission Computed Tomography is a brain scan using nuclear imaging to show how blood flows to tissues of the brain. A SPECT scan uses a CT scan and a radioactive material (tracer) to show how the blood flows to the brain tissues. The SPECT scan can show brain abnormalities and brain injuries.
These advances in imaging can help detect traumatic brain injuries.