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Published on: September 25, 2016
The donut sign: a new angiographic sign for partially thrombosed aneurysms with flow-induced intraluminal thrombus
Sanne B van Rooij1, Ratna S Bechan2, Jeroen E Markenstein3
1Department of Radiology, Medisch Centrum Alkmaar; Alkmaar, The Netherlands - wjjvanrooij@gmail.com.
Abstract:
Three patients are described with unruptured large partially thrombosed aneurysms with a peculiar donut-shaped remaining lumen. Observations suggest that the flow geometry of the aneurysm and parent vessels induces a preferential circular laminar flow inside the aneurysm followed by partial intraluminal thrombosis leaving a donut-shaped lumen to accommodate the circular flow. This flow mechanism of thrombus formation inside aneurysms is different from the more common repeated intramural dissections and hemorrhages that cause growth in most large and giant partially thrombosed aneurysms.
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