Three-dimensional computed tomographic angiography of cerebral aneurysms

Area of Science:

• Neurosurgery
• Radiology
• Medical Imaging

Background:

• Cerebral aneurysms pose significant risks, including subarachnoid hemorrhage and mass effect.
• Accurate anatomical visualization is crucial for effective treatment planning of complex or asymptomatic aneurysms.

Purpose of the Study:

• To evaluate the utility of dynamic, reconstructed, three-dimensional computed tomographic (3-D CT) angiography in assessing cerebral aneurysms.
• To determine the role of 3-D CT angiography in treatment planning for complex and asymptomatic aneurysms.

Main Methods:

• Dynamic, infused CT scans with 1.5-mm cuts were performed on 18 patients.
• Two-dimensional images were reconstructed into 3-D models using the ISG Allegro system.
• Results were compared with intra-arterial digital subtraction angiography and magnetic resonance angiography.

Main Results:

• 3-D CT angiography successfully demonstrated all aneurysms >3 mm and half of those ≤3 mm.
• The technique accurately visualized aneurysm neck, parent artery, associated branches, and adjacent bony structures (e.g., anterior clinoid).
• Partially thrombosed giant aneurysms and treated aneurysms were clearly depicted, with superior visualization of the active filling portion compared to MRI.

Conclusions:

• Dynamic, reconstructed 3-D CT angiography is a valuable tool for evaluating cerebral aneurysms.
• This technique is particularly useful when local anatomy is obscured or distorted by aneurysm mass or bony structures.
• 3-D CT angiography aids significantly in treatment planning, especially for ophthalmic aneurysms and complex cases.