Aneurysms

Question 1

Where is the most common intracranial aneurysm?

Answer 1

ACOMM

Question 2

What is the overall incidence of intracranial aneurysms? What is the risk of bleeding?

Answer 2

2-8%

1-2%

Question 3

What is the most common cause of spontaneous SAH?

Answer 3

Ruptured aneurysm

Question 4

What are the causes of convexity SAH in adults or kids?

Answer 4

Adults: amyloid, venous thrombosis

Younger: PRES, vasculitis

RARELY aneurysm

Question 5

What is the critical size for aneurysm rupture?

Answer 5

5-7mm

Question 6

Where does the blood occur in ruptured ACOMM?

Answer 6

Gyri recti, anterior interhemispheric fissue, septum pellucidum, frontal horns lateral ventricles

Question 7

What is the association with ACOMM aneurysm?

Answer 7

Azygous or fenestrated ACA

Question 8

What is the symptoms of PCOMM aneurysm?

Answer 8

Ipsilateral CN III palsy +/- SAH

Question 9

What is the 30 day mortality of intracranial aneurysm?

Answer 9

50%

Question 10

What is the major cause of intracranial aneurysms?

Answer 10

Hemodynamic stress

Question 11

Where is the blood in MCA bifurcation aneurysm?

Answer 11

Sylvian fissue, frontal opercula, basilar cisterns

Question 12

When is the greatest risk of rebleed in aneurysm rupture?

Answer 12

20-50% in first 2 weeks

Question 13

What are the diseases assocaited with intracranial aneurysm rupture?

Answer 13

FMD, ADPKD, connective tissue disorder, aortic coarctation, AVM, hypervascular tumors

Question 14

What is the size limit on MRA vs CTA

Answer 14

MRA detects 3mm

CTA 1mm

Question 15

Where is the bleed in basilar tip rupture?

Answer 15

basilar cisterns, posterior third ventricle

Question 16

Which area has increased risk of giant aneurysms?

Answer 16

Basilar tip

Question 17

What is the percentage of intracranial aneurysms with aortic aneurysms?

Answer 17

10% have an associated aortci aneurysm

Question 18

Where are infratentorial aneurysms most common? Where do they bleed?

Answer 18

PICA (origin, choroidal) > AICA/SCA

posterior fossa and 4th ventricle

Question 19

What percentage of intracranial aneurysms are multiple? Who gets multiple?

What are the associated conditions?

Which aneurysm bleeds?

Answer 19

10-15%

Female, family history

AVM, tumors, infections, collagen vasular disorders, SCD, moyamoya, AIDS

LArgest, irregular, lobulated, surrounded most by SAH, adjacent vasospasm

Question 20

What is a giant aneurysm? What are the types?

Answer 20

> 2.5cm

Thin wall - small ones that grew
Thick wall - bleeding into walls
Fusiform - postviral, collagen vascular
Serpentine - recanalized thrombosed aneurysm

Question 21

Where are the common sites of giant aneurysms?

Answer 21

ICA bifurcation, intracavernous ICA, MCA bifurcation, basilar artery tip

Question 22

What is the difference in rupture of thin vs thick walled aneurysms?

Answer 22

Thin will bleed into SAH

Thick will be intramural hematoma

Question 23

What is a pseudoaneurysm?

Answer 23

Posttraumatic secondary to tear in parent artery wall

Irregular shape

Question 24

Where are the common sites of pseudoaneurysm?

Answer 24

ICA bifurcation, ICA entrance into base of skull, cavernous sinus, supraclinoid segment

Vertebral artery as it enters foramen transversarium, C1 and C2, as it pierces dura and enters foramen magnum

Question 25

Which type of SAH is more likely to have vasospasm?

Answer 25

Nontraumatic

Question 26

What is the timeline for vasospasm after SAH?

Answer 26

Begins 3-5 days

Peaks 7-10 days

Lasts up to 3 weeks

Question 27

What is the treatment of SAH vasospasm?

Answer 27

Hypertension, Hyperhydration, Hypervolemia (Triple H)

Question 28

What velocity suggests vasospasm after SAH?

Answer 28

MCA velocity >120cm/s