Giant cerebral aneurysm

Giant cerebral aneurysms are ones that measure >25 mm in greatest dimension. 

Epidemiology

Giant cerebral aneurysms account for ~5% of all intracranial aneurysms ^1,3. They occur in the 5^th-7^th decades and are more common in females ².

Clinical presentation

Patients can present with symptoms and signs of mass effect or subarachnoid hemorrhage ^1,2.

Pathology

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

Location

Compared to non-giant cerebral aneurysms there is an increased incidence in the posterior circulation (~35%) ³.

Radiographic features

Appearances will depend on whether the aneurysm is non-thrombosed, or partially or completely thrombosed.

CT

• non-contrast: slightly hyperdense, well-defined round extra-axial masses ²
• may demonstrate a peripheral calcified rim

Treatment and prognosis

There are a variety of endovascular and open surgical techniques to treat these aneurysms. Endovascular options have a lower morbidity ³.

See also

• aneurysm
• saccular cerebral aneurysm
• ruptured berry aneurysm