Abstract
Four patients with large or giant carotid aneurysms treated by carotid ligation and extracranialintracranial (EC-IC) arterial bypass, and one patient with giant vertebral aneurysm treated by intracranial clipping of the vertebral artery were studied. Dynamic CT scan was employed to analyze the hemodynamic changes of the aneurysmal domes before and after surgery.
Preoperative dynamic CT scan revealed rapid transit of the contrast material in the aneurysmal dome which slowed within a few days after proximal artery ligation. The time-density curve of the aneurysmal dome remained flat up to 29 months after indicating that the aneurysmal lumen had become thrombosed. CT scan of a case showed ring enhancement of the aneurysmal wall 13 months after surgery. Dynamic CT scan in this case revealed slow transit of the contrast material, indicating that the ring enhancement was due to the presence of capillary vessels.
Patency of EC-IC bypass, completeness of proximal ligation, and lack of opacification of aneurysms were clearly demonstrated by digital subtraction angiography in all patients after surgery. Dynamic CT scan and digital subtraction angiography were useful for long-term follow-up after proximal artery ligation and EC-IC bypass for unclippable large intracranial aneurysms.
