title: Shoulder MR arthrography: intraarticular anesthetic reduces periprocedural pain and major motion artifacts but does not decrease imaging time.
abstract: OBJECTIVE
  To prospectively determine whether the addition of an intraarticular anesthetic to the magnetic resonance (MR) arthrography solution has an effect on periprocedural pain, motion artifacts, and imaging time.
  
  
  METHODS
  This study was approved by the institutional review board, and written informed consent was obtained from all patients. From September 2009 to March 2010, 127 patients, most imaged for shoulder pain, were randomized into two groups. The first group (group A, 63 patients) received intraarticular injection of gadopentetate dimeglumine, ropivacaine 0.5%, and normal saline in a ratio of 1:100:100. The second group (group B, 64 patients) received intraarticular injection of gadopentetate dimeglumine and normal saline in a ratio of 1:200. Pain was assessed before and after injection and immediately after 1.5-T MR imaging and rated on a scale of 0 to 10. Motion artifact was assessed by two musculoskeletal radiologists and two fellows by using a scale of 0 to 3 (0=no artifact, 1=artifact present but not affecting diagnostic image quality, 2=artifact present and diminishing diagnostic image quality, and 3=artifact present and rendering image nondiagnostic). MR imaging time and examinations with repeated sequences were recorded. Wilcoxon rank sum, analysis of covariance, and permutation data analyses were performed.
  
  
  RESULTS
  The mean pain levels before injection, after injection, and after MR imaging were 3.5, 2.3, and 2.5, respectively, for group A and 3.6, 3.1, and 3.2 for group B. After adjusting for age, sex, and preinjection pain level, the mean differences in pre- and postinjection pain and preinjection pain and post-MR imaging pain between the two groups were -0.9 (P=.017) and -0.8 (P=.056), respectively. No significant difference in mean total MR imaging time or number of patients with repeat sequences was noted. Radiologists 1 and 2 recorded grade 2 or 3 motion in six and five patients, respectively, in group A and 15 and 14 patients, respectively, in group B (P=.047 and .048, respectively). Radiologists 3 and 4 recorded grade 2 or 3 motion in 13 and 23 patients, respectively, in group A and 23 and 33 patients, respectively, in group B (P=.093 and .110, respectively).
  
  
  CONCLUSIONS
  The use of an intraarticular anesthetic significantly reduces periprocedural pain and major motion artifacts associated with MR shoulder arthrography; however, total MR imaging time is not reduced.
authors.affiliation: Department of Radiology, University of Virginia, 1218 Lee St, Box 800170, Charlottesville, VA 22908, USA. mf3kx@virginia.edu
authors.forename: Michael G
authors.initials: MG
authors.lastname: Fox
authors.forename: W Banks
authors.initials: WB
authors.lastname: Petrey
authors.forename: Bennett
authors.initials: B
authors.lastname: Alford
authors.forename: Bang H
authors.initials: BH
authors.lastname: Huynh
authors.forename: James T
authors.initials: JT
authors.lastname: Patrie
authors.forename: Mark W
authors.initials: MW
authors.lastname: Anderson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000577:Amides / Q000008:administration & dosage*; D000779:Anesthetics, Local / Q000008:administration & dosage; D018771:Arthralgia / Q000473:pathology* / Q000517:prevention & control*; D016477:Artifacts; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000187:drug effects; D015203:Reproducibility of Results; D000077212:Ropivacaine; D012680:Sensitivity and Specificity; D012785:Shoulder Joint / Q000187:drug effects* / Q000473:pathology*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D003287:Contrast Media; D000077212:Ropivacaine; D019786:Gadolinium DTPA