Natural History and Management of Basilar Trunk Artery Aneurysms

B asilar trunk artery is defined as the arterial segment from the origin of the basilar artery up to the origin of the superior cerebellar artery. Therefore, by definition, basi-lar tip and superior cerebellar artery aneurysms are excluded from the basilar trunk aneurysms (BTAs). BTAs are rare 1,2 and pose significant challenges to the treating physician: their cause is diverse, their natural history is poorly understood , and their treatment is challenging. Their 5-year mor-bidity–mortality is high, described as 80%, 3 and rupture of BTA is associated with a poor prognosis and high mortality rate within the first 48 hours. 4 Acute and chronic dissecting aneurysms of the basilar trunk are known to have severe morbidity and 20% to 30% mortality. 5 The higher frequency of giant fusiform aneurysms in the basilar trunk compared with the anterior circulation may reflect segmental vulnerability of this arterial system as previously proposed. 6 Management is challenging because of difficult surgical access, frequent occurrence of a broad-neck, and the incorporation of the perforating branches of the BA within the aneurysm. Treatment decisions are often complicated by an unpredictable clinical course and controversies on treatment strategy. Besides case reports, few large series have been published in the pertinent literature on management of these aneurysms. A better understanding of both the incidence and the natural history of these aneurysms may help to improve management strategies. Therefore, we describe herewith a single-center experience of the epidemiology, natural history, and management in 52 consecutive BTAs. patients were referred to our institution for the management of a cerebral aneurysm (58.3% unruptured and 41.7% ruptured; Figure 1). There were a total Background and Purpose—Basilar trunk aneurysms (BTAs), defined as aneurysms distal to the basilar origin and proximal to the origin of the superior cerebellar artery, are rare and challenging to manage. We describe the natural history and management in a consecutive series of BTAs. Methods—Between 2000 and 2013, 2522 patients with 3238 aneurysms were referred to our institution for aneurysm management. A retrospective review of this database was conducted to identify all patients with BTAs. Results—In total, 52 patients had a BTA. Mean age was 56 (SD±18) years. Median clinical follow-up was 33 (interquartile range, 8–86) months, and imaging follow-up was 26 (interquartile range, 2–80.5) months. BTAs were classified into 4 causal subtypes: acute dissecting aneurysms, segmental fusiform ectasia, mural bleeding ectasia, and saccular aneurysms. Multiple aneurysms were more frequently …