Intra-aneurysmal thrombosis as a possible cause of delayed aneurysm rupture after flow-diversion treatment.
OBJECTIVE
FD technology enables reconstructive repair of otherwise difficult-to-treat intracranial aneurysms. These stentlike devices may induce progressive aneurysm thrombosis without additional implants and may initiate complete reverse vessel remodeling. The associated vascular biologic processes are as yet only partially understood.


METHODS
From 12 different centers, 13 cases of delayed postprocedural aneurysm rupture were recorded and analyzed. Symptom, aneurysm location and morphology, and the time elapsed from treatment until rupture were analyzed.


RESULTS
There were 10 internal carotid and 3 basilar artery aneurysms. Mean aneurysm diameter was 22 ± 6 mm. Eleven patients were symptomatic before treatment. A single FD was used for all saccular aneurysms, while fusiform lesions were treated by using multiple devices. A supplementary loose coiling of the aneurysm was performed in 1 patient only. Ten patients developed early aneurysm rupture after FD treatment (mean, 16 days; range, 2-48 days); in 3 patients, rupture occurred 3-5 months after treatment. In all cases, most of the aneurysm cavity was thrombosed before rupture. The biologic mechanisms predisposing to rupture under these conditions are reviewed and discussed


CONCLUSIONS
FDs alone may modify hemodynamics in ways that induce extensive aneurysm thrombosis. Under specific conditions, however, instead of reverse remodeling and cicatrization, aggressive thrombus-associated autolysis of the aneurysm wall may result in delayed rupture.
Department of Neuroradiology, Swiss Neuro Institute Hirslanden, Clinic Hirslanden, Zurich, Switzerland. zsolt.kulcsar@hirslanden.ch
Z
Z
Kulcsár
E
E
Houdart
A
A
Bonafé
G
G
Parker
J
J
Millar
A J P
AJ
Goddard
S
S
Renowden
G
G
Gál
B
B
Turowski
K
K
Mitchell
F
F
Gray
M
M
Rodriguez
R
R
van den Berg
A
A
Gruber
H
H
Desal
I
I
Wanke
D A
DA
Rüfenacht
D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging* / Q000209:etiology*; D002548:Cerebral Revascularization / Q000009:adverse effects*; D005260:Female; D006801:Humans; D038622:Internationality; D002532:Intracranial Aneurysm / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery*; D020767:Intracranial Thrombosis / Q000150:complications* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D016896:Treatment Outcome