Rs-fMRI has been around for about 25 years and shows all of the major brain networks. Brain networks are areas of the brain that perform a function, such as moving the hand, processing visual information, or speaking. Each brain network uses oxygen in a coordinated manner. This oxygen use is detectable by the MRI scanner, because the oxygen is associated with iron - a metal in blood that carries the oxygen to the brain. The MRI magnet detects the changes of iron in the blood as the network uses the oxygen.
Normal brain networks use the oxygen in a predictable slow oscillating pattern, whereas atypical areas of the brain may use excess oxygen at an irregular pace. Thus abnormally functioning brain areas, even if they are anatomically normal, are detectable by rs-fMRI.
How rs-fMRI works
Rs-fMRI is done in a regular MRI machine. MRI is a safe, noninvasive, and advanced brain-imaging machine. The rs-fMRI takes about 20 minutes of scanner time. The patient lays awake or lightly sedated in the scanner. The patient must lay still during the procedure, or motion may corrupt the images. Most children cannot lay perfectly still this long and PCH is accustomed to administering light sedation to help. Afterward, the child goes home. The results are analyzed by Dr. Boerwinkle and typically available within a week, though expedited analysis is available, if indicated.
Advantages of using rs-fMRI
- Localization of serious brain pathology, such as where seizures occur.
- Identification of the major brain networks. This helps in understanding what capacities the child may develop over time. Also, helps neurosurgeons see where major brain networks are to avoid them if possible during surgery, reducing the chances of lost capacities.
- Helps doctors understand in those with reduced consciousness, such as coma, the capacity to recover consciousness. Some children appear to be unconscious, but are actually awake, or may have seizures not seen by EEG. Rs-fMRI has unique findings in these conditions to help doctors treat patients.