Radiology.Academy.Sk

Neuro Review
Appendix
Spleen
Stomach
Kidneys
Kidney
Pancreas
Pelvic congestion syndrome
Liver
Biliary
CT Abd Epiploic Appendagitis
Fractures Wrist
Wrist
Diffuse periosteal reaction
Signs in Uroradiology
Male breast
MRI Breast Indications
CT Head Cerebellar Mass
Biopsies
Diagnostic mammography
Screening mammography
Mammo Pearls
ACR Appropriateness Criteria Breast Cancer Screen
AVM types
CT Orbits
CT Abd NL
Chiari Malformations
Vesicoureteral Reflux (VUR)
Elbow
XRAY Abdominal Series

Abdomen
Cardio
Chest
Dictation Templates
General
GU
Mammography
MSK
neuro
Neuroradiology
NM
Nuclear Medicine
Pediatric
Physics
Ultrasound
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Brain Aneurysms

  • 5% of population, risk of bleeding 1% per year in previously non-ruptured aneurysms
  • 90% of all intracranial aneurysms arise from Circle of Willis (COW)
  • 90% of subarachnoid hemorrhage (SAH) is from aneurysm
  • SAH in old patient: 1.) Amyloid, 2.) Venous thrombosis
  • SAH in young pt: 1.) PRES, 2.) Vasculitis (almost never aneurysm)
  • 90% ruptures occur between 30-70 yrs
  • Aneurysms < 5 mm are unlikely to rupture (critical size 5-7 mm)
  • Rupture results in hydrocephalus in 10% of pts
  • 50% of patients will die within 30 days following initial rupture
  • Almost all aneurysms are result of hemodynamic stress, only 2% are found in children
  • Risk of rebleeding 20-50% during the 2 wks following initial rupture
  • Increased risk for aneurysm: FMD, PCKD, vasculitis, aortic coarctation, AVMs, hypervascular tu (GBM, meningioma) --> MRA screening


A-COMM: Anterior Communicating Artery Aneurysm

30% of intracranial aneurysms. SAH into gyri recti, anterior interhemispheric fissure, septum pellucidum, frontal horns of lateral ventricles. Most common to show intra-axial hemorrhage (then MCA, P-Comm, Basilar)


P-COMM: Posterior Communicating Artery Aneurysm

30%. May be mirror-like, ipsilateral 3rd CN palsy or SAH: diffuse, temporal, perimesencephalic or may be concentrated into basilar cisterns


MCA Bifurcation Aneurysm

30%, may be mirror-like; SAH in Sylvian fissure, frontal opercula, basilar cisterns


Basilar Artery Tip Aneurysm

10%, SAH in basilar cisterns and 3rd ventricle, increased incidence of giant aneurysms in this location


Infratentorial Aneurysms

1%, SAH into posterior fossa and 4th ventricle. PICA aneurysm at origin and choroidal points. AICA and SCA are dissecting in nature


Multiple Intracranial Aneurysms

which aneurysm bled? largest, irregular, lobulated (excrescence sign), surrounded by clot or SAH, adjacent vasospasm, A-comm