From the Guidelines
The annual risk of pericallosal anterior cerebral artery brain aneurysm rupture is approximately 0.05% per year for aneurysms <10 mm in diameter and ≈1% per year for larger aneurysms, as indicated by the ISUIA study 1.
Factors Influencing Rupture Risk
The risk of rupture varies based on several factors, including:
- Aneurysm size: larger aneurysms (>7mm) carry higher rupture risks of up to 3-4% annually 1
- Location: aneurysms in the posterior circulation or posterior communicating artery have higher rupture risks compared to those in the anterior circulation 1
- History of subarachnoid hemorrhage (SAH): patients with a history of SAH from a different aneurysm have a higher rupture risk, approximately 0.5% per year for those <10 mm and ≈0.7% per year for larger aneurysms 1
Patient-Specific Factors
Patient-specific factors that increase rupture risk include:
- Smoking
- Hypertension
- Family history of aneurysmal subarachnoid hemorrhage
- Certain genetic conditions like polycystic kidney disease
Management Decisions
Management decisions should be individualized, weighing the natural rupture risk against treatment risks, considering the patient's age, comorbidities, and life expectancy. Regular monitoring with non-invasive imaging is typically recommended for small, unruptured aneurysms, while surgical clipping or endovascular coiling may be considered for higher-risk aneurysms.
Key Considerations
Key considerations in managing pericallosal anterior cerebral artery brain aneurysms include:
- Aneurysm size and location
- Patient-specific risk factors
- Natural history of the aneurysm
- Treatment risks and benefits Based on the most recent and highest quality study, the ISUIA study 1, the annual risk of pericallosal anterior cerebral artery brain aneurysm rupture can be estimated, and management decisions can be made accordingly.
From the Research
Annual Risk of Pericallosal Anterior Cerebral Artery Brain Aneurysm Rupture
The annual risk of pericallosal anterior cerebral artery brain aneurysm rupture is not explicitly stated in the provided studies. However, some studies provide information on the rupture risk of pericallosal artery aneurysms:
- A study published in 2020 2 found that 22 out of 45 pericallosal artery aneurysms (48.9%) had ruptured, indicating a high propensity for rupture.
- Another study published in 2017 3 reported that 32 patients with ruptured pericallosal artery aneurysms were admitted to the hospital between 1999 and 2014, but it does not provide a specific annual risk.
- A study published in 2017 4 reported that 42% of the aneurysms were ruptured, but it does not provide information on the annual risk of rupture.
Factors Associated with Rupture Risk
Some studies suggest that certain factors are associated with an increased risk of rupture:
- A study published in 2020 2 found that pericallosal artery aneurysms have unique morphological characteristics, including increased aspect ratio, size ratio, and inflow angle, which may contribute to their high propensity for rupture.
- A study published in 2017 3 found that poor admission status, cerebral infarction, and smoking are associated with an unfavorable outcome after subarachnoid hemorrhage from pericallosal artery aneurysms.
Treatment and Outcome
The treatment and outcome of pericallosal artery aneurysms are also discussed in the studies:
- A study published in 2018 5 reported that patients with spontaneous pericallosal artery aneurysms had good clinical outcomes after endovascular coiling or microsurgical clipping treatment.
- A study published in 2017 4 reported that there was no mortality due to surgery in 19 patients who underwent surgical treatment for distal anterior cerebral artery (pericallosal artery) aneurysms.