title: The donut sign: a new angiographic sign for partially thrombosed aneurysms with flow-induced intraluminal thrombus.
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.
authors.affiliation: Department of Radiology, Medisch Centrum Alkmaar; Alkmaar, The Netherlands - wjjvanrooij@gmail.com.
authors.forename: Sanne B
authors.initials: SB
authors.lastname: van Rooij
authors.affiliation: Department of Radiology, St Elisabeth Ziekenhuis; Tilburg, The Netherlands.
authors.forename: Ratna S
authors.initials: RS
authors.lastname: Bechan
authors.affiliation: Department of Radiology, St Elisabeth Ziekenhuis; Tilburg, The Netherland.
authors.forename: Jeroen E
authors.initials: JE
authors.lastname: Markenstein
authors.affiliation: Department of Radiology, St Elisabeth Ziekenhuis; Tilburg, The Netherland.
authors.forename: Menno
authors.initials: M
authors.lastname: Sluzewski
authors.affiliation: Department of Radiology, St Elisabeth Ziekenhuis; Tilburg, The Netherland.
authors.forename: Willem Jan
authors.initials: WJ
authors.lastname: van Rooij
mesh_terms: D000368:Aged; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging*; D002533:Cerebral Angiography / Q000379:methods*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications* / Q000000981:diagnostic imaging*; D020767:Intracranial Thrombosis / Q000000981:diagnostic imaging* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
keywords: 3D rotational angiography; intracranial aneurysm; partial thrombosis