Contents

Search

cerebral aneurysm; intracranial aneurysm; subarachnoid aneurysm

Epidemiology: - 7% of Chinese patients age 35-75 years - more common in women (8.6% vs. 5.5%) [4] - ~20% of patients with a cerebral aneurysm have a first-degree relative with a brain aneurysm [9] Pathology: - most cerebral aneurysms are small (< 5 mm) [4] - < 1% of cerebral aneurysms > 10 mm [4] - distal internal carotid artery is the most common site [4] h Clinical manifestations: - focal neurologic deficits may occur from compression of cranial nerve - dilated pupil from cranial nerve 3 palsy Radiology: - neuroimaging - CT angiography - magnetic resonance angiography - repeat neuroimaging yearly - interval may be extended to 2 or 3 years if stable [5] - see subarachnoid hemorrhage if rupture of cerebral aneurysm suspected Complications: cerebral aneurysm rupture - subarachnoid hemorrhage a) both size & location predict risk of hemorrhage b) main risk factors are hypertension & smoking c) low-risk areas 1] common carotid artery a] < 12 mm; 5 year risk of hemorrhage 0% b] > 25 mm; 5 year risk of hemorrhage 6% 2] posterior circulation - < 7 mm 0.1% per year [3,5] d) high-risk areas 1] vertebrobasilar artery 2] posterior cerebral artery 3] posterior communicating artery 4] 3-50% 5 year risk of hemorrhage, depending upon size e) intermediate risk areas 1] anterior communicating artery 2] internal carotid artery 3] middle cerebral artery - cerebral edema (large aneurysm) [9] - cerebral vasospasm resulting from subarachnoid hemorrhage begins 3-4 days after aneurysm rupture & most frequently peaks in 7-10 days [5] Management: 1) observation vs surgery - sometimes a difficult choice balancing natural history with risks of treatment - incidental cerebral aneurysms < 7-12 mm are followed by MRI - < 7 mm in posterior circulation or < 12 mm in anterior circulation [5] - surgery for larger cerebral aneurysms - endovascular coiling vs clipping - blood pressure control - smoking cessation to reduce risk of aneurysm rupture [5] 2) endovascular coiling with detachable platinum coil device a) risk of procedure-related death 3% b) 10% with moderate-severe neurologic disability 1 year after repair 3) surgical clipping of aneurysm 4) at 10 years, outcomes better with coiling than clipping (mortality 17% vs 21%) [7,8] - more rebleeding with coiling than clipping 13 vs 6 of 1644 patients, but only 6 of 13 rebleeds from coiling vs 4 of 6 rebleeds from clipping resulted in death or dependency [7] 5) thrombectomy & aneurysmal repair (large aneurysm) [9] 6) neurovascular stenting - treat wide-neck, intracranial, saccular aneurysms [10] - excess periprocedural stroke & mortality reported with inappropriate patient selection [10] 7) prophylaxis for cerebral vasospasm with ruptured cerebral aneurysm - nimodipine 30-60 mg every 4 hours

Related

International subarachnoid Aneurysm Trial (ISAT)

Specific

cerebral berry aneurysm

General

brain aneurysm

Database Correlations

OMIM 105800

References

  1. Journal Watch 23(1):2, 2003 International subarachnoid Aneurysm Trial (ISAT) Collaborative Group, Lancet 360:1267, 2002 Nichols DA et al, Lancet 360:1262, 2002
  2. Journal Watch 23(17):136, 2003 International subarachnoid Aneurysm Trial (ISAT) Collaborative Group, Lancet 362:103, 2003 PMID: 12414200
  3. The UCAS Japan Investigators. The natural course of unruptured cerebral aneurysms in a Japanese cohort. N Engl J Med 2012 Jun 28; 366:2474. PMID: 22738097
  4. Li M-H et al. Prevalence of unruptured cerebral aneurysms in Chinese adults aged 35 to 75 years: A cross-sectional study. Ann Intern Med 2013 Oct 15; 159:514 PMID: 24126645 http://annals.org/article.aspx?articleid=1748842
  5. Medical Knowledge Self Assessment Program (MKSAP) 16, 17, 18, 19. American College of Physicians, Philadelphia 2012, 2015, 2018, 2021 - Medical Knowledge Self Assessment Program (MKSAP) 19 Board Basics. An Enhancement to MKSAP19. American College of Physicians, Philadelphia 2022
  6. Wiebers DO, Whisnant JP, Huston J 3rd et al Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment. Lancet. 2003 Jul 12;362(9378):103-10. PMID: 12867109
  7. Molyneux AJ et al. The durability of endovascular coiling versus neurosurgical clipping of ruptured cerebral aneurysms: 18 year follow-up of the UK cohort of the International Subarachnoid Aneurysm Trial (ISAT). Lancet 2014 Oct 28 PMID: 25465111 http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2814%2960975-2/fulltext
  8. Thompson BG, Brown RD Jr, Amin-Hanjani S et al. Guidelines for the management of patients with unruptured intracranial aneurysms: A guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke 2015 Jun 18 PMID: 26089327
  9. Patel NJ, Filippidis A IMAGES IN CLINICAL MEDICINE. A Giant Aneurysm of the Anterior Communicating Artery. N Engl J Med 2015; 373:560. August 6, 2015. http://www.nejm.org/doi/full/10.1056/NEJMicm1413193
  10. FDA Safety Watch. May 8, 2018 Neurovascular Stents Used for Stent-Assisted Coiling (SAC): Letter to Health Care Providers - Recommendations Associated With the Use of These Devices in the Treatment of Unruptured Brain Aneurysms. https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm607024.htm
  11. NINDS Cerebral Aneurysm Information Page https://www.ninds.nih.gov/Disorders/All-Disorders/Cerebral-Aneurysms-Information-Page