Aneurysms of the Posterior Cerebral Artery: Classification and Endovascular Treatment

Giant serpentine aneurysm of the P2A segment of the PCA presenting with intracerebral and subarachnoid hemorrhage in a 12-year-old boy.

A, Noncontrast CT scan of the head shows the large partially clotted aneurysm in the perimesencephalic cistern, associated with SAH.

B, Towne's view of the vertebral angiogram shows the residual lumen of the partially clotted aneurysm (arrow), non-filling of the distal branches of the ipsilateral PCA, and avascular mass effect on the brain stem structures (arrowheads).

C, The lumen of the aneurysm and the parent artery were permanently occluded with GDC. The nonsubtracted Towne's view shows the metallic cast of the coils.

D, The corresponding subtracted image of the posttreatment vertebral angiogram shows complete obliteration of the aneurysm.

Successful obliteration of a ruptured saccular aneurysm of the PCA with preservation of the parent artery.

A, The oblique subtracted view of a vertebral angiogram shows an irregular bilobed saccular aneurysm arising from the origin of the P3/P4 segments. The patient is a 52-year-old woman presenting with acute SAH.

B, The oblique nonsubtracted view of the posttreatment vertebral angiogram shows the cast of the GDC obliterating the aneurysm with preservation of the parent artery.

C, The oblique subtracted view of the follow-up vertebral angiogram, obtained 2 years after the treatment, shows persistent obliteration of the aneurysm.

Parent artery occlusion of a giant serpentine aneurysm of the PCA complicated by cerebral infarction in the distal arterial territory.

A, Axial T2-weighted MR image of the head showing a giant serpentine aneurysm of the P2/P3 segments of the left PCA.

B, Towne's view of a left vertebral angiogram showing the serpentine nature of the giant aneurysm, which involves the P2 and P3 segments of the left PCA.

C, Subtracted Towne's view of the posttreatment vertebral angiogram shows obliteration of the aneurysm and no antegrade flow in the distal branches of the left PCA. Note the retrograde flow from the cortical branches of the ipsilateral middle cerebral artery (arrows).

D, Homonymous hemianopsia and contralateral hemiparesis complicated the treatment. The posttreatment axial T2-weighted MR image shows an acute infarction in the distribution of the left PCA territory.

P1 segment aneurysm associated with a distal cortical AVM.

A, Pretreatment Towne's view of a vertebral angiogram showing a P1 segment aneurysm associated with a temporooccipital AVM. Note the poor ratio of the fundus of the aneurysm to the size of its neck.

B, Same view of the vertebral angiogram after the endovascular treatment of the aneurysm with GDC

C, Follow-up vertebral angiogram obtained 42 months after the initial treatment showing complete obliteration of the AVM and questionable minimal residual filling of the aneurysm.