Type:
Educational Exhibit
Keywords:
Interventional vascular, Vascular, Emergency, CT-Angiography, Catheter arteriography, Diagnostic procedure, Embolisation, Stents, Haemorrhage
Authors:
F. Carchesio1, R. Iezzi2, A. Posa1, R. Manfredi2; 1Roma/IT, 2Rome/IT
DOI:
10.1594/ecr2018/C-2537
Background
Pseudoaneurysm is an enlargement of an arterial vessel which lack a complete arterial wall,
leading to a high risk of rupture with consequent bleeding,
thus requiring treatment.
Pseudoaneurysms are mostly asymptomatic and are consequences of trauma,
infections or surgical procedures,
after direct damage of the vessel wall.
The gold standard in pseudoaneurysm's diagnosis is the multidetector-row computed tomography (MDCT) examination,
which is a panoramic methodic,
helping in the assessment of the vessel from which the pseudoaneurysm originated and in detection of its cause.
Digital Subtraction Angiography (DSA) is nowadays used mostly for treatment purposes; it is a dynamic technique which permits to evaluate the flow in the sac and the presence of collateral vessels.
The choice of material or method to exclude the pseudoaneurysm’s sac from the circulation mostly depends on the type,
the size and the course of the vessel,
on the presence of collateral circles,
and the downstream parenchima or the tissue supplied.
Endovascular exclusion of pseudoaneurysm’s sac from the circulation can be achieved with stents,
coils or particles: stent preserves the patency of the vessel,
whereas the placement of space-occupying material (coils,
particles) in the target vessel helps achieving endoluminal thrombosis.
Embolization procedures are usually preferred in pseudoaneurysms involving distal vessels:
- Coils are metallic structures with a great variety of shapes and sizes,
and could be “pushable” or “detachable”; the latter,
in which the coil remains linked to the tip of the pushing wire,
facilitates a more accurate and controlled deployment,
allowing replacement in the vessel until the target location is reached.
Often,
multiple coils are needed for vessel occlusion.
Coils could be detached with “sandwich technique”,
upstream and downstream the sac,
to exclude it in presence of collateral circles.
- Particulate materials,
represented by gelatin sponge and injectable “cast-forming” liquids (like n-butyl cyanoacrylate,
ethylene vinyl alcohol copolymer) are used to embolize more distal vessels.
Also gelatin sponge and thrombin can be used to give rise to endoluminal coagulation.
- Vascular plugs are complex metallic structures that,
once placed in the target vessel,
determine a mechanical occlusion,
obtaining thrombosis and immediate resolution of the bleeding.
On the other hand,
among the vascular stents,
covered stents are used to preserve the patency of the artery when main visceral vessels,
in particular in their proximal segment,
are treated; however,
they have a high percentage of occlusion.