title: Simultaneous bilateral magnetic resonance angiography to evaluate thoracic outlet syndrome.
abstract: OBJECTIVE
  This paper presents a new magnetic resonance angiography (MRA) protocol for the evaluation of thoracic outlet syndrome (TOS) that allows for a separate assessment of veins and arteries while using a single, simultaneous and bilateral (SB-MRA) single contrast injection, valid for both abduction and adduction acquisitions.
  
  
  METHODS
  From 2009 to 2013 we performed 38 MRA studies for clinically suspected TOS (13 M, 25 F; mean age, 35.9 years; σ = 11.13). Twin peripheral 20G intravenous catheters were placed in a cubital vein in both arms and connected to a single power injector by two lines joined with a connector. A 3T MR system with a wide gantry was used. Two groups of four radiologists assessed all the images. Group A judged the full examinations, Group B had only the late acquisitions. Differences were evaluated using the Chi square test. TOS was confirmed only after integration with the clinical history.
  
  
  RESULTS
  Seventeen (45 %) patients were diagnosed with predominant venous TOS (VTOS), nine (24 %) with predominant arterial TOS (ATOS) and 12 (32 %) had an indeterminate or nonvascular condition. Group A radiologists identified significantly more VTOS than group B (p = 0.049). Interobserver agreement was very high.
  
  
  CONCLUSIONS
  SB-MRA is a safe and reliable protocol for the study of TOS. It provides a supplementary early acquisition that allows for separate assessment of veins and arteries, permits the investigation of the collateral venous flow with a single injection of contrast material and provides a higher diagnostic power for VTOS. SB-MRA is helpful for the diagnosis of TOS of vascular origin.
authors.affiliation: Dipartimento di Radiologia, IRCCS Istituto Clinico Humanitas, Via Alessandro Manzoni, 56, 20089, Rozzano, MI, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Poretti
authors.forename: Ezio
authors.initials: E
authors.lastname: Lanza
authors.forename: Luca Maria
authors.initials: LM
authors.lastname: Sconfienza
authors.forename: Giovanni
authors.initials: G
authors.lastname: Mauri
authors.forename: Vittorio
authors.initials: V
authors.lastname: Pedicini
authors.forename: Luca
authors.initials: L
authors.lastname: Balzarini
authors.forename: Francesco
authors.initials: F
authors.lastname: Sardanelli
mesh_terms: D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007275:Injections, Intravenous; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013901:Thoracic Outlet Syndrome / Q000175:diagnosis* / Q000209:etiology
chemical_list: D003287:Contrast Media