Two cases of internal carotid artery aneurysm arising within the petrous bone are described, bringing up to 56 the number of such cases reported to date in the medical literature scanned through Medline. The first case presented as a moderately bleeding tumor of the petrous apex, while the second was revealed by a massive otorrhage. In both cases a pulsatile nasopharyngeal mass was associated with otorrhage. The treatment required in both cases the aneurysm to be embolized in extreme emergency. One patient suffered transient hemiplegia and aphasia that completely recovered, while the second eventually died, although the carotid occlusion had been well tolerated in the first two weeks that followed this procedure. From their own experience and a literature review, we can emphasize the need for arterial extra-intracranial bypass before an aneurysm embolization be proposed, since the neurological issue following internal carotid occlusion cannot be predicted.