FIG 3. Case 2, a 54-year-old man with an unruptured left internal carotid–posterior communicating artery aneurysm.

Operative photographs before (A) and after (B) surgical dissection of the embedded aneurysmal dome, showing the aneurysm (An), the internal carotid artery (C1, C2), the posterior communicating artery (PComA), posterior clinoid process (PC), and the temporal lobe (TL).

C, 3D MR angiogram, similar projection to the operative views in panels A and B, showing the aneurysmal complex. Note the slight difference in terms of the aneurysmal shape and small protrusions on the parent artery (arrowheads).

D, 3D CT angiogram, similar projection with the operative views in panels A and B, showing the aneurysmal complex and cranial base bone similarly.

E, Conventional 3D MR cisternogram, similar projection to the operative views in panels A and B, depicting the contours of the aneurysmal complex (An, C1, C2, PComA), the posterior clinoid process bone (PC), the petroclinoidal dural fold (PF), and the temporal lobe (TL).

F, Transparent 3D MR cisternogram, the same projection as in panel E, depicting the whole shape of the aneurysm (An) and parent arteries (C1, C2, PComA) in blue, transparently through the vessel wall and the adjacent brain surface (green and red).