title: Quantification of Respiratory Movement of the Aorta and Side Branches.
abstract: OBJECTIVE
  To assess and quantify the magnitude and direction of respiratory movement of the aorta and origins of its side branches.
  
  
  METHODS
  A quantitative 3-dimensional (3D) subtraction analysis of computed tomography (CT) scans during inspiration and expiration was performed to determine the respiratory geometric movements of the aorta and side branches in 60 patients. During breath-hold expiration and inspiration, 1-mm-thick CT slices of the aorta were acquired in unenhanced and contrast-enhanced scans. The datasets were compared using dedicated multiplanar reformation image subtraction software to determine the change in position of relevant anatomic sections, including the ascending thoracic aorta (AA), the origins of the brachiocephalic artery (BA) and left subclavian artery (LSA), the descending thoracic aorta (DTA) at the level of the tenth thoracic vertebra, as well as the origins of the celiac trunk, superior mesenteric artery, and the renal arteries.
  
  
  RESULTS
  Complex movement was visible during inspiration; the regions of interest in the thoracic aorta and side branches moved in the anterior, medial, and caudal directions compared with the expiration state. Mean 3D movement vectors (± standard deviation) were 8.9±3.6 mm (AA), 12.0±4.1 mm (BA), 11.1±3.9 mm (LSA), and 4.9±2.5 mm (DTA). Abdominal side branches moved in the caudal direction 1.3±1.1 mm. There was significantly less movement in the DTA compared to AA (p<0.001). The correlation coefficient between the extent of LSA movement and thoracic excursion was 0.78.
  
  
  CONCLUSIONS
  The aorta and side branches undergo considerable respiratory movement. The results from this study provide an important contribution to understanding aortic dynamics.
authors.affiliation: Department of Radiology, Maastricht University Medical Centre, Maastricht, The Netherlands karmanna@stanford.edu.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Sailer
authors.affiliation: Department of Radiology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Bart A J M
authors.initials: BA
authors.lastname: Wagemans
authors.affiliation: Department of Radiology, Maastricht University Medical Centre, Maastricht, The Netherlands CARIM, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Marco
authors.initials: M
authors.lastname: Das
authors.affiliation: Department of Radiology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Michiel W
authors.initials: MW
authors.lastname: de Haan
authors.affiliation: Department of Epidemiology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Nelemans
authors.affiliation: Department of Radiology, Maastricht University Medical Centre, Maastricht, The Netherlands CARIM, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Joachim E
authors.initials: JE
authors.lastname: Wildberger
authors.affiliation: CARIM, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands Department of Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Geert Willem H
authors.initials: GW
authors.lastname: Schurink
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000502:physiology*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009068:Movement; D011446:Prospective Studies; D012119:Respiration; D014057:Tomography, X-Ray Computed
keywords: aortic motion; ascending aorta; computed tomography; descending aorta; fusion image guidance; respiration; stent-graft; thoracic aorta; thoracic endovascular aortic repair