title: Shaken or swirled? Mixing gadolinium for arthrography.
abstract: OBJECTIVE
  To better understand how variability in preparation of gadolinium solutions may affect image quality for MRI arthrography studies.
  
  
  METHODS
  Two different mixing techniques were employed in preparation of gadolinium/saline dilutions (repeated inversion vs. swirling). Test syringes were then placed together with unmixed and control syringes in a specially prepared holder in the MRI machine and both initial and delayed T1FS sequences were performed. Qualitative assessment was performed to evaluate completeness of contrast mixing and overall signal intensity of contrast within the syringe. Quantitative measurements were performed using a circular region of interest centered on the lumen of each syringe. Three trials were performed.
  
  
  RESULTS
  Subjective and quantitative analysis revealed that the repeatedly inverted syringe demonstrated more uniform high signal with lower standard deviation than the swirled syringe in all three trials. Subjective evaluation of the swirled syringe revealed contrast/saline levels on both initial and delayed scans. The syringe that was not mixed after addition of gadolinium demonstrated even more obvious dependant layering of contrast than did the swirled syringe on both initial and delayed scans.
  
  
  CONCLUSIONS
  When preparing small volumes of diluted gadolinium solution for intraarticular injection, the technique of mixing may influence the composition of the injected solution.
authors.affiliation: Department of Medical Imaging, Royal University Hospital, 103 Hospital Drive, Saskatoon, Saskatchewan, Canada, S7N 0W8. andrew.denton@gmail.com
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Scott
authors.forename: David
authors.initials: D
authors.lastname: Leswick
mesh_terms: D003287:Contrast Media / Q000737:chemistry*; D008279:Magnetic Resonance Imaging; D009942:Organometallic Compounds / Q000737:chemistry*; D019047:Phantoms, Imaging; D012996:Solutions; D013594:Syringes
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D012996:Solutions; C112666:gadoversetamide