Unruptured intracranial aneurysm

AAN 2015 guideline

  • Link to original article = please read the original article
  • Unruptured intracranial aneurysm = UIA
  • Subarachnoid hemorrhage = SAH

Risk factors and recommendations

  • Smoking increase risks of UIA: smoking cessation
  • Hypertension may play a role in growth and rupture: treat Hypertension
  • Intermittent imaging studies needed to follow the size of UIA

Diagnosis and imaging

  • DSA is most sensitive imaging
  • CTA, MRA are useful
  • Coiled aneurysms, especially with wider neck or have residual filling, should have follow up evaluation.

Screening recommendation

  • Patients with 2 or more family members with intracranial aneurysm or SAH, should be offered screening with CTA or MRA
  • history of autosomal dominant polycystic kidney disease, or coarctation of aorta

Natural history – recommendations

  • Prior history of aneurysm rupture, at risk for smaller aneurysm rupture
  • Documented enlargement during follow up should be offered treatment
  • Family history of Intracranial aneurysm, treatment may be offered even a smaller aneurysm size

Natural history of UIA – based on studies isuia and ucas Japan

  • No history of SAH and aneurysm < 7mm
    • anterior circulation: no rupture
    • risks of rupture in post circulation: 2.5%/year
  • history of SAH, size < 7mm
    • Risk of rupture anterior circulation: 1.5%/year
    • Risk of rupture post circulation: 3.4%/year
  • Risk factors for rupture includes
    • > 60 years old
    • Female
    • Japanese or Finish descent
    • symptomatic aneurysm
    • diameter > 5mm
    • posterior circulation
  • Overall rupture rate for aneurysm <7 mm is 0.4%/year

Additional reading

Patient educational video

3 Ways Doctors Can Treat Your Brain Aneurysm