Functional MRI (fMRI) is a technique for measuring activity in specific areas of the brain by detecting changes in blood oxygenation and flow to these areas in response to specific neural activity. fMRI is then used to produce activation maps demonstrating parts of the brain involved in particular activities. This technology therefore has diverse applications including:
Tumour surgery planning: Safe and accurate tumour surgical planning is made possible by defining the relationship of tumours to eloquent areas of the brain prior to surgery. By knowing this relationship between lesion and normal eloquent areas of the brain it is possible for the surgeons to plan resection in such a way as to minimise injury to the normal surrounding brain.
Epilepsy surgery management: In patients with epilepsy, the cortical functions are often re-organised because of structural malformations that cause epilepsy. Mapping of eloquent cortex responsible for motor, language, memory and sensory functions is therefore essential prior to planning surgery for epilepsy.
Dementia: Since fMRI can help evaluate the memory networks of the brain and therefore has some role in the management of dementia, specifically in Alzheimer’s disease. Functional MRI is capable of demonstrating any impaired activation of the hippocampus and surrounding structures in patients with Alzheimer’s disease using memory encoding tasks.
Traumatic brain injury: Alterations in cognition following traumatic brain injury can be assessed by fMRI. Change in activity levels of certain parts of the brain such as the frontal and parietal areas correlate well with traumatised brains and can be used for follow up of these patients as well.
Psychiatric disorders: fMRI has also shown to assist in the delineation of the neural circuitry that is hypothesised to underlie major depression and associated psychiatric disorders. This may have a role in the follow up of patients and in assessment of response to treatment.