Management of Unruptured Intracranial Aneurysms

Abstract

See related article, pages 899–904 . In the retrospective analysis of their experience in treating 173 patients with 202 unruptured intracranial aneurysms (UIAs) with endosaccular coiling over a 12 year span from 1992 through August 2004, Standhardt et al1 document treatment outcomes with low morbidity and mortality but highly variable efficacy relative to durable, complete aneurysm obliteration. Such has been the experience of other investigators.2 Although the reported data are of interest, numerous questions remain, including the comprehensive postprocedure assessment of morbidity and mortality, and risk of adverse outcomes compared to natural history. In this series 48% of the aneurysms were incidentally discovered, and approximately 30% were “other” aneurysms in patients having experienced hemorrhage from another aneurysm, so-called Group II patients in the International Study of Unruptured Intracranial Aneurysms (ISUIA),3 and 14% were symptomatic due to mass effect (typically larger aneurysms). Nearly 44% of these aneurysms were small in size (<7 mm diameter), 37% of medium size (7 to 12 mm) and nearly 20% large to giant in dimension. About half of the aneurysms had a small neck (<4 mm in breadth) which is commonly regarded as optimal for endosaccular coiling assuming no complicating anatomy such as branches arising from the aneurysm base or conditions such as existence of intraluminal thrombus. Relative to procedural risk, particularly as compared to those of craniotomy and aneurysm clipping, the results which these operators have achieved are excellent—mortality in 0.5% …