Three-dimensional angiographic demonstration of plexiform fenestrations of the proximal anterior cerebral artery associated with a ruptured aneurysm.

A rare case of ruptured aneurysm associated with multiple A(1) fenestrations resembling plexiform network was demonstrated by 3D angiography. A 56-year-old female presented with a ruptured aneurysm in the A(2) segment of the left distal anterior cerebral artery associated with the right A(1) fenestration. The ruptured aneurysm was occluded with surgical neck clipping via interhemispheric approach without neurological deficit. Plexiform fenestrations of the right distal A(1), opposite side to the left ruptured A(2) aneurysm, were clearly visible on postoperative 3D angiography. Our case may strongly support the theory described by Paget, namely that a remnant of the plexiform anastomosis between the primitive olfactory artery and A(1) segment is the source of such fenestration.