Surgical treatment of large and giant cavernous carotid aneurysms

Abstract

Cavernous carotid aneurysms (CCAs) are uncommon pathologic entities. Extradural place and the skull base location make this type of an aneurysm different in clinical features and treatment techniques. Direct aneurysm clipping is technically difficult and results in a significant postoperative neurological deficit. Therefore, several techniques of indirect surgical treatment were developed with different surgical outcomes, such as proximal occlusion of internal carotid artery (ICA) or trapping with or without bypass (superficial temporal artery-middle cerebral artery bypass or high-flow bypass). High-flow bypass with proximal ICA occlusion seems to be the most appropriate surgical treatment for CCA because of the high rate of symptom improvement, aneurysm thrombosis, and minimal postoperative complications. However, in cases of CCA presented with direct carotid-cavernous fistula, the appropriate surgical treatment is high-flow bypass with aneurysm trapping, which the fistula can be obliterated immediately after surgery.

Keywords: Cavernous carotid aneurysm; giant aneurysm; high-flow bypass; intracavernous carotid aneurysm; large aneurysm; proximal occlusion; surgical treatment; trapping.

Figure 1

(a) Trapping (cervical internal carotid artery ligation with clipping of C3 segment of internal carotid artery, just proximal to ophthalmic artery origin) of cavernous carotid aneurysm with high-flow bypass. (b) Cervical internal carotid artery ligation with high-flow bypass. Both techniques result in the complete aneurysm thrombosis. First segment of anterior cerebral artery (A1), anterior choroidal artery, first segment of middle cerebral artery (M1), second segment of middle cerebral artery (M2), ophthalmic artery (OphA), posterior communicating artery (PcoA), and radial artery graft (RAG)

Figure 2

Modified from Takahashi et al. (a) first operation. (b) second operation for “blind-alley formation”. Basilar artery (BA), superior cerebellar artery (SCA)

Figure 3

(a) A partially thrombosed giant basilar tip aneurysm. (b) The maximal flow reduction strategy (“blind-alley formation”) (modified from Miyamoto et al.)

Figure 4

Scheme demonstrates (a) aneurysm and (b) treatment using “blind-alley formation” strategy (modified from Shimizu et al.)

Figure 5

Scheme demonstrates the thrombosis of cavernous carotid aneurysm by proximal internal carotid artery occlusion as “blind-alley formation” strategy

Figure 6

Surgical treatment of cavernous carotid aneurysm presented with direct carotid-cavernous fistula. (a) By only proximal internal carotid artery occlusion, the fistula was not obliterated completely. (b) Complete obliteration of carotid-cavernous fistula accomplished by trapping of the aneurysm was able to immediately decrease blood flow to the fistula