The middle frontal gyrus, like the inferior frontal gyrus and the superior frontal gyrus, is more of a region than a true gyrus.
The middle frontal gyrus is frequently divided longitudinally by the intermediate sulcus. The surgeon should not confuse the intermediate sulcus with the superior frontal sulcus or inferior frontal sulcus. The inferior frontal sulcus is often interrupted, so the surgeon performing a subpial tumor dissection in the middle frontal gyrus may inadvertently wander into the inferior frontal gyrus. A break in the inferior frontal sulcus over the pars triangularis allows the surgeon removing a middle frontal lesion to wander into Broca’s area.
The middle frontal gyrus is comparable with the Broca area in its ability to determine hemispheric dominance for language using resting state functional magnetic resonance imaging. Results suggest the addition of resting-state fMRI of the middle frontal gyrus to the list of noninvasive modalities that could be used in patients with gliomas to evaluate hemispheric dominance of language before tumor resection. In patients who cannot participate in traditional task-based fMRI, resting-state fMRI offers a task-free alternate to pre surgically map the eloquent cortex 2).