Natural history of dolichoectatic vertebrobasilar aneurysms: a multinational study

J Neurosurg 142:1376–1386, 2025

This multinational study of 382 patients reveals dolichoectatic vertebrobasilar aneurysms (DVBAs) have a high annual mortality (10.8%) and morbidity (1.6%). Advanced age (>50 years), basilar artery location, and large aneurysm size predict worse outcomes, supporting early invasive treatment when feasible to improve prognosis.

• Dolichoectatic vertebrobasilar aneurysms (DVBAs) are rare, malignant vascular lesions with high morbidity and mortality.

• Largest multinational study to date analyzed 382 patients with DVBAs from 11 centers in Europe, US, and Japan.

• Most patients were male (68.6%), median age at diagnosis was 58.8 years.

• Annual adverse event, mortality, and morbidity rates were 12.4%, 10.8%, and 1.6% respectively.

• Older age (>50 years), basilar artery location, larger aneurysm size (>25 mm), and type II (dolichoectatic) morphology were key risk factors for poor outcomes.

• Highest risk of adverse events and death occurred within the first year after diagnosis, especially in older patients and those with basilar artery involvement.

• Early invasive treatment is encouraged when feasible, based on age and radiological characteristics.

• Study highlights urgent need for new, safer therapeutic options for DVBAs.

Bypass surgery of complex middle cerebral artery aneurysms—technical aspects and outcomes

Acta Neurochirurgica (2019) 161:1981–1991

The main challenge of bypass surgery of complex MCA aneurysm is not the selection of the bypass type, but the initial decision making of how to exclude the affected vessel segment from circulation. The aim of our study was to review our experience with the treatment of complex MCA aneurysms using revascularization and parent artery sacrifice techniques. Based on this, we aimed at categorizing these aneurysms according to specific surgical aspects in order to facilitate preoperative planning for these challenging surgical pathologies.

Methods We reviewed 50 patients with complex MCA aneurysms that were not clippable but required revascularization and parent artery sacrifice. We report the individual variations of surgical techniques, highlight the technical aspects, and categorize the aneurysms based on their location and orientation.

Results Of the 50 aneurysms, 56% were giant, 16% large, and 28% < 10 mm, but fusiform. Fourteen percent were previously treated endovascular. Four percent presented with SAH. Ten percent were prebifurcational, 60% involved the bifurcation, and 30% were postbifurcational. Both parent artery sacrifice and bypass strategies were tailored to the individual localization and anatomical relationship of the aneurysm and inflow/outflow arteries (38% proximal inflow occlusion, 42% aneurysm trapping, 20% distal outflow occlusion; 14% STA-MCA bypass, 48% interposition graft, 36%, combined/complex revascularization with reimplantation/in situ techniques). Good outcome (mRS 0–2) rates at discharge and at follow-up were 64% and 84%. Based on our analysis of individual cases, we categorized complex MCA aneurysms into six types and provide individual recommendations for their surgical exploration and treatment by revascularization and parent artery sacrifice.

Conclusion Complex MCA aneurysms are among the most challenging vascular lesions and afford highly individualized treatment strategies. Revascularization and parent artery sacrifice provide durable results that are superior to the natural history. Our classification provides a tool for planning and pre-surgical assessment of the intraoperative anatomy of complex MCA aneurysms, helping to assume possible pitfalls.

Double-barrel STA to proximal MCA bypass and proximal parent artery occlusion for a fusiform superior clinoidal ICA aneurysm

Acta Neurochirurgica (2018) 160:1939–1943

Blood flow replacement and parent artery occlusion are alternative treatments of complex fusiform superior clinoidal ICA aneurysms. While double-barrel STA to proximal MCA bypass is a conventional approach among these reported bypass algorithms, its technical details remain underexplored.

Method We have applied the double-barrel STA to proximal MCA bypass and parent artery occlusion to treat a 45-year-old female patient with a right fusiform superior clinoidal ICA aneurysm. The technical nuances of this approach are reported.

Conclusion We show that double-barrel STA to proximal MCA bypass and proximal parent artery occlusion can be alternative treatments of complex fusiform superior clinoidal ICA aneurysms.

Twenty-Year Follow-up of Flow Reversal and Revascularization for a Giant Serpentine Basilar Artery Aneurysm

Twenty-Year Follow-up of Flow Reversal and Revascularization for a Giant Serpentine Basilar Artery Aneurysm

Operative Neurosurgery 10:E493–E497, 2014

Current microsurgical and endovascular therapies have offered little advancement for the treatment of complex vertebrobasilar aneurysms. The outcome of patients with these rare lesions has remained poor, despite sometimes heroic measures.

CLINICAL PRESENTATION: The authors report a case of a 65-year-old man who 20 years earlier had presented with symptoms suggestive of brainstem compression. Imaging at the time revealed a giant, serpentine aneurysm of the basilar artery. The patient was treated with superficial temporal artery to superior cerebellar artery bypass and decompression of the aneurysm contents. Twenty years after this treatment, the patient remains functionally intact with few sequelae from his treatment or the pathology. Follow-up imaging reveals thrombosis of the aneurysm without ischemic damage to the brainstem.

CONCLUSION: This case demonstrates that good functional outcomes are possible for select complex posterior circulation aneurysms by using flow reversal and revascularization; however, at this time, we are unable to predict for which patients this strategy will be successful.

KEY WORDS:

Treatment of Distal Posterior Cerebral Artery Aneurysms: A Critical Appraisal of the Occipital Artery-to-Posterior Cerebral Artery Bypass

Neurosurgery 67:16-26, 2010 DOI: 10.1227/01.NEU.0000370008.04869.BF

This is the largest contemporary series of distal posterior cerebral artery (PCA) aneurysms treated by use of endovascular coiling and stenting as well as surgical clipping, clip wrapping, and bypass techniques. We propose a new treatment paradigm.

METHODS:The location, size, type of aneurysm, clinical presentation, treatment, complications, and outcomes associated with 34 distal PCA aneurysms in 33 patients (15 females, 18 males; mean age, 44 years) were reviewed retrospectively.

RESULTS: The most common presenting symptom was headache in 19 (58%) followed by contralateral weakness or numbness in 6 (18%) and visual changes in 4 (12%). Eight aneurysms were giant. Of the remaining 26 aneurysms, 17 were fusiform/dissecting, 5 were saccular, and 4 were mycotic. Treatment was primarily endovascular in 22 patients, 12 of whom also had a concomitant surgical bypass procedure. Nine patients underwent microsurgical clipping, and 3 underwent combined treatment of clipping and coiling and/or stenting. There were no significant differences in outcomes between the groups (P = .078). The recurrence rate in patients undergoing coiling was 22% and 0% in patients undergoing clipping. Fourteen aneurysms (41%) involved treatment with an occipital artery-to-PCA bypass or an onlay graft. Compared with their preoperative status, these patients had significantly worse outcomes than those without a bypass (P = .013).

CONCLUSION: Bypass techniques for the treatment of distal PCA aneurysms are associated with a higher rate of complications than once thought. In our new treatment paradigm, bypass is a last resort and reserved for patients in whom balloon-test occlusion fails, who refuse parent-vessel sacrifice, and who cannot undergo primary stenting with coiling or clip wrapping.