Sign, M

The M sign can be seen on the sagittal MRI brain located at the inferior frontal gyrus, indicating the location of the frontal operculum—pars orbitalis, pars triangularis (Brodmann area 45), and pars opercularis (Brodmann area 44). Together, pars triangularis and pars opercularis are identified as Broca's area.

Cases

1

This MRI sagittal image clearly depicts the M sign, composed of the pars orbitalis (green line), pars triangularis (red V), and pars opercularis (blue line). Additionally, please notice the presence of superior temporal encephalomalacia, which is secondary to an old ICH.