"De novo" aneurysms. A clinical review.

The authors present seven cases drawn from 620 consecutive cases over 30 years, in which previously undemonstrated (hence "de novo") intracranial aneurysms formed and ruptured at intervals of 3-20 years, after clipping of an initial aneurysm. Six patients were treated for rupture of a second aneurysm. All six had undergone successful treatment of a previous aneurysm; pre- and postoperative angiography showed not only successful clipping of the first aneurysm but also no incidence of multiple aneurysms. In no case was a major artery occluded at the time of the initial surgery. The implications as to natural history and the advisability of repeated arteriography in some patients with aneurysms are discussed.