title: Multimodality imaging assessment of the deleterious role of the intraluminal thrombus on the growth of abdominal aortic aneurysm in a rat model.
abstract: OBJECTIVE
  To evaluate imaging changes occurring in a rat model of elastase-induced abdominal aortic aneurysm (AAA), with emphasis on the intraluminal thrombus (ILT) occurrence.
  
  
  METHODS
  The post-induction growth of the AAA diameter was characterized using ultrasound in 22 rats. ILT was reported on 13 rats that underwent 14 magnetic resonance imaging (MRI) 2-18 days post-surgery, and on 10 rats that underwent 18 fluoro-deoxyglucose (FDG) positron emission tomography (PET)/microcomputed tomography examinations 2-27 days post-surgery. Logistic regressions were used to establish the evolution with time of AAA length, diameter, ILT thickness, volume, stratification, MRI and FDG PET signalling properties, and histological assessment of inflammatory infiltrates.
  
  
  RESULTS
  All of the following significantly increased with time post-induction (p < 0.001): AAA length, AAA diameter, ILT maximal thickness, ILT volume, ILT iron content and related MRI signalling changes, quantitative uptake on FDG PET, and the magnitude of inflammatory infiltrates on histology. However, the aneurysm growth peak followed occurrence of ILT approximately 6 days after elastase infusion.
  
  
  CONCLUSIONS
  Our model emphasizes that occurrence of ILT precedes AAA peak growth. Aneurysm growth is associated with increasing levels of iron, signalling properties changes in both MRI and FDG PET, relating to its biological activities.
  
  
  CONCLUSIONS
  • ILT occurrence in AAA is associated with increasing FDG uptake and growth. • MRI signalling changes in ILT reflect activities such as haemorrhage and RBC trapping. • Monitoring ILT activities using MRI may require no exogenous contrast agent.
authors.affiliation: Department of Medical Imaging, University Hospital Liège, Liège, Belgium. anchimi@chu.ulg.ac.be.|GIGA cardiovascular diseases, University Hospital Liège, Domaine Universitaire du Sart-Tilman B 35, B - 4000, Liege, Belgium. anchimi@chu.ulg.ac.be.
authors.forename: Alain
authors.initials: A
authors.lastname: Nchimi
authors.affiliation: Laboratory of Connective Tissue Biology, GIGA-R, University of Liège, Liège, Belgium.
authors.forename: Audrey
authors.initials: A
authors.lastname: Courtois
authors.affiliation: Department of Medical Imaging, University Hospital Liège, Liège, Belgium.
authors.forename: Mounia
authors.initials: M
authors.lastname: El Hachemi
authors.affiliation: Surgical Research Center, GIGA-Cardiovascular diseases, University of Liège, Liège, Belgium.
authors.forename: Ziad
authors.initials: Z
authors.lastname: Touat
authors.affiliation: Department of Experimental Surgery and Animal Care, University Hospital Liège, Liège, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Drion
authors.affiliation: Department of Nuclear Medicine, University Hospital Liège, Liège, Belgium.
authors.forename: Nadia
authors.initials: N
authors.lastname: Withofs
authors.affiliation: Cyclotron Research Center, University of Liège, Liège, Belgium.
authors.forename: Geoff
authors.initials: G
authors.lastname: Warnock
authors.affiliation: Cyclotron Research Center, University of Liège, Liège, Belgium.
authors.forename: Mohamed-Ali
authors.initials: MA
authors.lastname: Bahri
authors.affiliation: Department of Pharmacy, Namur Thrombosis and Hemostasis Center (NTHC), Namur Research Institute for Life Sciences (NARILIS), University of Namur, Namur, Belgium.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Dogné
authors.affiliation: Department of Cardiovascular Surgery, University Hospital Liège, Liège, Belgium.|Surgical Research Center, GIGA-Cardiovascular diseases, University of Liège, Liège, Belgium.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Cheramy-Bien
authors.affiliation: Department of Medical Imaging, University Hospital Liège, Liège, Belgium.
authors.forename: Laurent
authors.initials: L
authors.lastname: Schoysman
authors.affiliation: Department of Medical Imaging, University Hospital Liège, Liège, Belgium.
authors.forename: Julien
authors.initials: J
authors.lastname: Joskin
authors.affiliation: INSERM & Cardiology Department, Bichat Hospital, AP-HP, Paris, France.
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Michel
authors.affiliation: Department of Cardiovascular Surgery, University Hospital Liège, Liège, Belgium.
authors.forename: Jean-Olivier
authors.initials: JO
authors.lastname: Defraigne
authors.affiliation: Cyclotron Research Center, University of Liège, Liège, Belgium.
authors.forename: Alain
authors.initials: A
authors.lastname: Plenevaux
authors.affiliation: Department of Cardiovascular Surgery, University Hospital Liège, Liège, Belgium.
authors.forename: Natzi
authors.initials: N
authors.lastname: Sakalihasan
mesh_terms: D000818:Animals; D001011:Aorta / Q000000981:diagnostic imaging; D017544:Aortic Aneurysm, Abdominal / Q000150:complications* / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D008297:Male; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography; D051381:Rats; D017208:Rats, Wistar; D013927:Thrombosis / Q000150:complications* / Q000000981:diagnostic imaging* / Q000473:pathology; D055114:X-Ray Microtomography
keywords: Aneurysm; Aorta; Imaging; Iron; Thrombus