Giant vertebrobasilar junction aneurysms: unusual cases.

Giant vertebrobasilar (VB) junction aneurysms are uncommon aneurysms, especially those associated with multiple aneurysms of the posterior circulation. We report two cases, one with a small and a giant aneurysm of the VB junction which were surgically clipped; and the other with a small left anterior inferior cerebellar artery (AICA) aneurysm which resolved spontaneously. The patient, however, developed a de-novo giant VB junction aneurysm, which was detected on a follow-up angiogram. This aneurysm was treated by surgical clipping. The clinical features, angiographic considerations and surgical treatment of such rare conditions are discussed and the relevant literature reviewed.