Let's start with an representative clinical case, processed in our neuroimaging software suite, BrainMagix. The patient has a brain tumor at the junction of the left temporal, parietal, and occipital lobes. The tumor is close to Wernicke's area of language. Therefore, an fMRI examination was carried out, in order to localize the language network (yellow and blue blobs), and thereby help the neurosurgeon to maximize the tumor resection while minimizing the post-operative deficit. Now that we understand its clinical interest, let's try to understand how fMRI works! Like for any other MRI examination, the patient is lying in the MRI scanner.

Let's start with an representative clinical case, processed in our neuroimaging software suite, BrainMagix. The patient has a brain tumor at the junction of the left temporal, parietal, and occipital lobes. The tumor is close to Wernicke's area of language. Therefore, an fMRI examination was carried out, in order to localize the language network (yellow and blue blobs), and thereby help the neurosurgeon to maximize the tumor resection while minimizing the post-operative deficit. Now that we understand its clinical interest, let's try to understand how fMRI works! Like for any other MRI examination, the patient is lying in the MRI scanner.

Let's start with an representative clinical case, processed in our neuroimaging software suite, BrainMagix. The patient has a brain tumor at the junction of the left temporal, parietal, and occipital lobes. The tumor is close to Wernicke's area of language. Therefore, an fMRI examination was carried out, in order to localize the language network (yellow and blue blobs), and thereby help the neurosurgeon to maximize the tumor resection while minimizing the post-operative deficit. Now that we understand its clinical interest, let's try to understand how fMRI works! Like for any other MRI examination, the patient is lying in the MRI scanner.

The detection of brain areas which are used during a condition is based on the Blood Oxygenation Level Dependent (BOLD) effect. When neurons are activated, the resulting increased need for oxygen is overcompensated by a larger increase in perfusion. As a result, the venous oxyhemoglobin concentration increases and the deoxyhemoglobin concentration decreases. As the latter has paramagnetic properties, the intensity of the fMRI images increases in the activated areas. As the conditions are alternated, the signal in the activated voxels increases and decreases according to the paradigm.

The variation of the BOLD signal induced by the paradigm is very low ( < 2%) and cannot be detected visually. Therefore, advanced statistical methods must be used to identify the voxels in which the signal varies according to the paradigm. In a first step, the images are pre-processed: (slice-timing correction), realignment of fMRI series to correct patient movements, registration with an anatomical scan, (spatial normalization to a brain atlas), (segmentation), and spatial filtering. In a second step, the pre-processed images are statistically analyzed, with a model describing the experiment (e.g. the general linear model). Thresholded fMRI activation maps can be overlaid in color on a high resolution anatomical MR image or displayed on a 3D reconstruction of the brain. BrainMagix's fMRI Module performs a user-friendly analysis of clinical fMRI images.