Distal basilar artery aneurysms: conditions for safe and secure clipping.

In general, vertebro-basilar aneurysms are good indications for endovascular treatment. However, basilar artery (BA) bifurcation aneurysms, BA-superior cerebellar artery (SCA) aneurysms, and sometimes mid-basilar aneurysms are also good indications for clipping. In this paper, conditions for safe and secure clipping for distal basilar aneurysms are discussed.There are several tips for the clipping of distal BA aneurysms. Among them, the following are very important: patency of the perforators, posterior cerebral artery (P1), and SCA must always be maintained. Several modalities including micro-Doppler ultrasonography and indocyanine green video-angiography (ICGVA) should be used to confirm the patency of these vessels. Each confirmation of patency of the vessels after clipping must be compared to those from before the clipping. Intra-operative digital subtraction angiography (DSA) is needed for large or giant aneurysms.