Giant cerebral aneurysms are ones that measure >25 mm in greatest dimension.
Giant cerebral aneurysms account for ~5% of all intracranial aneurysms 1,3. They occur in the 5th-7th decades and are more common in females 2.
Patients can present with symptoms and signs of mass effect or subarachnoid haemorrhage 1,2.
Most commonly represent saccular cerebral aneurysms but may also be fusiform or serpentine in morphology 1. They are thought to develop via two pathways 2:
- internal elastic lamina de novo defect
- enlargement from a smaller aneurysm
Compared to non-giant cerebral aneurysms there is an increased incidence in the posterior circulation (~35%) 3.
Appearances will depend on whether the aneurysm is non-thrombosed, or partially or completely thrombosed.
- non-contrast: slightly hyperdense, well-defined round extra-axial masses 2
- may demonstrate a peripheral calcified rim
Treatment and prognosis
There are variety of endovascular and open surgical techniques to treat these aneurysms. Endovascular options have a lower morbidity 3.
- 1. Castillo M. Neuroradiology Companion: Methods, Guidelines, and Imaging Fundamentals. LWW. ISBN:1451111754. Read it at Google Books - Find it at Amazon
- 2. Mehta RI, Salamon N, Zipser BD et-al. Best cases from the AFIP: giant intracranial aneurysm. Radiographics. 2010;30 (4): 1133-8. doi:10.1148/rg.304095199 - Pubmed citation
- 3. van Rooij WJ, Sluzewski M. Endovascular treatment of large and giant aneurysms. AJNR Am J Neuroradiol. 2008;30 (1): 12-8. doi:10.3174/ajnr.A1267 - Pubmed citation