[Giant aneurysm of fast development].

The percentage of aneurysms measuring more than 2'5 cm in diameter ranges from 3 to 13%, and occur more commonly in females. They come to clinical attention later than nongiant aneurysms, but 20% of them appear in patients 20 years of age or younger. Its natural history is incompletely understood. We present the case of a 24-year-old female admitted following a generalized seizure with postictal dysphasia and right hemiparesis caused by a subarachnoid hemorrhage due to a ruptured giant aneurysm located in the left temporal fossa, who died few hours later because of rebleeding. This patient had been followed during the last seven years at our unit because of untreated frontal osteomas, without evidence of any intracranial lesion in the computerized axial tomography (CT). Some months before her death, she had suffered a left micotic otitis, and she was studied because of the reappearance of her left cephalalgia without neurological deficit. This case is another evidence of quick appearance of a giant aneurysm, "silent" until the fatal outcome.