title: Multifactorial relationship between 18F-fluoro-deoxy-glucose positron emission tomography signaling and biomechanical properties in unruptured aortic aneurysms.
abstract: BACKGROUND
  The relationship between biomechanical properties and biological activities in aortic aneurysms was investigated with finite element simulations and 18F-fluoro-deoxy-glucose (18F-FDG) positron emission tomography.
  
  
  RESULTS
  The study included 53 patients (45 men) with aortic aneurysms, 47 infrarenal (abdominal aortic) and 6 thoracic (thoracic aortic), who had ≥1 18F-FDG positron emission tomography/computed tomography. During a 30-month period, more clinical events occurred in patients with increased 18F-FDG uptake on their last examination than in those without (5 of 18 [28%] versus 2 of 35 [6%]; P=0.03). Wall stress and stress/strength index computed by finite element simulations and 18F-FDG uptake were evaluated in a total of 68 examinations. Twenty-five (38%) examinations demonstrated ≥1 aneurysm wall area of increased 18F-FDG uptake. The mean number of these areas per examination was 1.6 (18 of 11) in thoracic aortic aneurysms versus 0.25 (14 of 57) in abdominal aortic aneurysms, whereas the mean number of increased uptake areas colocalizing with highest wall stress and stress/strength index areas was 0.55 (6 of 11) and 0.02 (1 of 57), respectively. Quantitatively, 18F-FDG positron emission tomographic uptake correlated positively with both wall stress and stress/strength index (P<0.05). 18F-FDG uptake was particularly high in subjects with personal history of angina pectoris and familial aneurysm.
  
  
  CONCLUSIONS
  Increased 18F-FDG positron emission tomographic uptake in aortic aneurysms is strongly related to aneurysm location, wall stress as derived by finite element simulations, and patient risk factors such as acquired and inherited susceptibilities.
authors.affiliation: Departments of Cardiovascular and Thoracic Imaging.
authors.forename: Alain
authors.initials: A
authors.lastname: Nchimi
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Cheramy-Bien
authors.forename: T Christian
authors.initials: TC
authors.lastname: Gasser
authors.forename: Gauthier
authors.initials: G
authors.lastname: Namur
authors.forename: Pierre
authors.initials: P
authors.lastname: Gomez
authors.forename: Laurence
authors.initials: L
authors.lastname: Seidel
authors.forename: Adelin
authors.initials: A
authors.lastname: Albert
authors.forename: Jean-Olivier
authors.initials: JO
authors.lastname: Defraigne
authors.forename: Nicos
authors.initials: N
authors.lastname: Labropoulos
authors.forename: Natzi
authors.initials: N
authors.lastname: Sakalihasan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*; D017545:Aortic Aneurysm, Thoracic / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology*; D001027:Aortography / Q000379:methods; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D005260:Female; D020342:Finite Element Analysis; D019788:Fluorodeoxyglucose F18; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011379:Prognosis; D019275:Radiopharmaceuticals; D012039:Regional Blood Flow; D012307:Risk Factors; D013314:Stress, Mechanical; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D051598:Whole Body Imaging
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: aneurysm; aorta; tomography