ACA aneurysm

Note the prominent pulsation artifact in the first image (a FSE T1-weighted scan at 3 T), seen propagating in the left-right dimension. On the post-contrast image (a short TE GRE scan), the aneurysm is well depicted, other than partial volume effects (due to the 4 mm slice thickness). This 2D scan is relatively immune to pulsation artifacts due to the short TE (2.9 msec in this instance). Thick MIP axial and coronal sections from a 3D TOF exam depict the aneurysm well, with both A2 segments originating from the aneurysm, and absence (aplasia) of the left A1 segment.

ACA aneurysm
Part of the on-line supplement to Neuroradiology – The Essentials with MR and CT (© 2015)