Aneurysm

Question 1

An aneurysm is the protrusion of the wall of a blood vessel. How can aneurysms be classified?

Answer 1

Aneurysms can be classified by the following:

• shape
• how it happened
• composition (true aneurysm or false)

Question 2

What is the difference between a true aneurysm and a false aneurysm?

Answer 2

True aneurysms comprise all three layers of a blood vessel

False aneurysms comprise a thick fibrous layer, usually due to scarring/trauma of the blood vessel

Question 3

What are the different shapes that aneurysms can adopt?

Answer 3

Saccular (large spherical outpouching)
Fusiform (spindle-like)
Cylindrical
Serpentine/varicose
Racemose/circoid

Question 4

Aneurysms can also be classified according to the pathogenetic mechanisms that contribute to their formation. Name some common causes.

Answer 4

Aneurysms can be caused by the following:

• atherosclerosis
• syphilis (found most common in the tertiary stage)
• dissecting (blood enters and fills the dissected wall of the blood vessel)
• mycotic (post-microbial infection)
• berry aneurysm (these commonly affect blood vessels in the circle of Willis in the brain

Question 5

What are the characteristic features of atherosclerotic-induced aneurys

Answer 5

Atherosclerotic-induce aneurysms are typically:

• infra-renal - just above the bifurcation of the aorta (they may extend to the iliac arteries)
• vary in size but typically 5-6 cm in diameter
• lumen of aneurysm typically contains thrombus
• can vary in morphology, but typically adopts a fusiform (spindle-like) shape

Question 6

What are the clinical manifestations of an aneurysm?

Answer 6

Clinical manifestations of an aneurysm are:

• rupture (the rupture of an abdominal aneurysm may result in blood filling in the peritoneum or retroperitoneum)
• compression onto other structures
• arterial occlusion

Question 7

Where are post-syphilitic aneurysms typically localised? What are the clinical manifestations of syphiltiic aneurysms?

Answer 7

post-syphilitic aneurysms are typically localised in the ascending aorta and aortic arch

Question 8

What are the clinical manifestations of post-syphilitic aneurysms?

Answer 8

• rupture (just like with atherosclerotic aneurysms); syphilitic ruptures may occur in the pleural cavity, pericardial sac, trachea and oesophagus
• compression may affect the trachea, oesophagus, recurrent laryngeal nerve
• ## cardiac malfunctioning (this occurs if the aortic root and valves are affected)

Question 9

What are the bones of the skull?

Answer 9

1 x occipital bone
1 x frontal bone
2 x temporal bone
2 x parietal bone
1 x sphenoid bone
1 x ethmoid bone