Bracket sign (pars marginalis)
The bracket sign of the pars marginalis, also known as the pars bracket sign, refers to the appearances of the superior most extent of the pars marginalis of the cingulate sulcus on axial imaging. It forms two roughly symmetric brackets, open anteriorly. The next sulcus anteriorly is the central sulcus.
It should not be confused with the bracket sign of pericallosal lipomas.