Usefulness of 3D rotational angiography for stent–assisted coiling in dissecting aneurysm of the posterior cerebral artery

Abstract

  Dissecting cerebral aneurysms of the posterior cerebral artery (PCA) are rare, and it is difficult to treat aneurysms located in the P1 or P2 segment by microsurgery because of the difficulty in confirming the perforating arteries to the brain stem and thalamus. We report the case of a ruptured dissecting cerebral aneurysm of the PCA in which we identified the perforators of the P1 segment adjacent to the dissecting aneurysm using a CT‒like reconstruction from three‒dimensional (3D) rotational angiography (3DRA). Stent‒assisted coil embolization was performed without ischemic complications. A 46‒year‒old Japanese man was admitted to our hospital complaining of loss of consciousness. CT revealed a subarachnoid hemorrhage (SAH), and a cerebral angiogram demonstrated a dissecting aneurysm of the right P1‒2 segment. The patient was selected for conservative treatment in the early stages. Significant aneurysm enlargement was observed at 12 days post‒admission on a cerebral angiogram. Volume rendering and CT‒like reconstructions from 3DRA confirmed that the perforators to the midbrain and thalamus were apart from the dissecting aneurysm, and we thus decided to perform stent‒assisted coil embolization and finished the embolization with the neck remnant. At 6 days after treatment, a cerebral angiogram revealed disappearance of the cerebral aneurysm, and MRI did not reveal an iatrogenic cerebral infarction. The patient did not present any symptoms of SAH following his endovascular treatment. This case demonstrates that the evaluation of the perforators to the brainstem using CT‒like reconstructions from 3DRA is useful for performing an intravascular treatment of dissecting aneurysms of the PCA without ischemic complications.