April 29, 2008 - A new neuroimaging study aims to ensure the highest quality of life for patients by assessing their cognitive skills before, during and after brain tumor surgery, by mapping the important functional brain areas surrounding the tumor in order to decrease the risks during surgery, at the Montreal Neurological Institute and Hospital at McGill University.
This new study by researchers at the Montreal Neurological Institute and Hospital, published recently in the Journal of Neurosurgery, looks at functional neuroimaging in patients undergoing surgery for the removal of brain tumors. This is done in order to localize important functional areas of the brain so that these can be preserved during the surgical procedure.
Functional magnetic resonance imaging (fMRI) has been used extensively to map sensory and motor functions, as well as to define brain regions involved in language processes but, until now, has not been applied to higher-order cognitive functions such as memory. Patients with brain tumors can lead active lives for extended periods following surgery and it is therefore important to consider the preservation of cognitive functions that depend on brain regions close to the tumor in order to maintain the patients' autonomy, and a good postoperative quality of life.
While in the fMRI scanner, preoperative brain tumor patients are asked to complete a task that assesses the function of the dorsal premotor cortex by requiring them to select between competing actions based on conditional rules. This preoperative fMRI data is then integrated into an image-guided neuronavigation system, which guides neurosurgeons during surgery optimizing the approach for tumor removal in patients and preserving relevant functional regions in the premotor cortical region of the brain.
Patients then undergo post-operative structural MR imaging to show that the resection of the tumor was optimal and that the functional region within the brain's premotor cortex that was involved in the performance of the cognitive task was preserved. Patients in this study showed no deficits in their performance of the task postoperatively, further demonstrating that this specific cognitive function was not altered.