Vascular Geometry Associated with Anterior Communicating Artery Aneurysm Formation

Area of Science:

• Neurosurgery
• Radiology
• Vascular Neurology

Background:

• Anterior communicating artery (ACoA) aneurysms are a significant cause of subarachnoid hemorrhage.
• Identifying morphologic risk factors for ACoA aneurysm formation is crucial for early detection and prevention.

Purpose of the Study:

• To identify clinical and morphologic risk factors correlated with anterior communicating artery (ACoA) aneurysm formation.
• To determine if specific vascular morphologic features independently predict ACoA aneurysm presence.

Main Methods:

• Retrospective analysis of 3D imaging (CTA/DSA) from 504 patients with ACoA aneurysms and 201 controls.
• Evaluation of A1 segment patency (hypoplastic/aplastic) and parent/daughter vessel dimensions and angles.
• Univariable and multivariable statistical analyses, including sensitivity analyses for small aneurysms.

Main Results:

• Aplastic and hypoplastic A1 segments were significantly more prevalent in patients with ACoA aneurysms.
• Multivariable analysis confirmed that a hypoplastic A1 segment is independently associated with ACoA aneurysms.
• The A2-ACoA angle showed association but was likely a consequence of aneurysm presence, not an independent risk factor.

Conclusions:

• A hypoplastic A1 segment is the sole morphologic parameter independently associated with ACoA aneurysms, irrespective of aneurysm size.
• This finding can serve as a simple screening parameter for identifying individuals at risk for ACoA aneurysms.
• Further research can explore the clinical utility of A1 segment hypoplasia in aneurysm screening protocols.