title: MR arthrography of the shoulder, hip, and wrist: evaluation of contrast dynamics and image quality with increasing injection-to-imaging time.
abstract: OBJECTIVE
  The purpose of our study was to investigate the contrast dynamics and the relationship between visualization of intraarticular structures and time elapsed between intraarticular injection of contrast agent and MRI in symptomatic patients referred for MR arthrography of the shoulder, hip, and wrist.
  
  
  METHODS
  Our local ethics committees and the national drug administration approved this multicentric study. We prospectively studied 11 shoulders, 11 hips, and 10 wrists. After the intraarticular gadolinium injection, patients underwent a baseline MR arthrography protocol (time point [TP] 1) and subsequent MRI at another four time points (TP 2-TP 5) up to 240 minutes. The course of contrast-to-noise ratio (CNR) over time was calculated. Three observers assessed the degree of visualization of different intraarticular structures and the overall image quality at each time point using a 3-point scale and a 5-point scale, respectively.
  
  
  RESULTS
  For all joints, CNR measurements showed peak CNR at TP 1 (21 minutes) and TP 2 (45 minutes) with a subsequent, near-logarithmic decline of CNR values over time. Visualization of different anatomic structures decreased over time. Overall image quality was insufficient for diagnostic purposes at TP 3 (96 minutes) in three (27%) of 11 shoulders and in three (27%) of 11 hips. In two (20%) of 10 wrists, image quality was insufficient at TP 2 (45 minutes).
  
  
  CONCLUSIONS
  For MR arthrography, the degree of visualization of intraarticular structures depends on the time elapsed between contrast injection and MRI. MR arthrography of the shoulder and hip should be performed within 90 minutes, and MR arthrography of the wrist should be performed within 45 minutes, after intraarticular injection.
authors: Institute for Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland.
authors: Gustav
authors: G
authors: Andreisek
authors: Sylvain R
authors: SR
authors: Duc
authors: Johannes M
authors: JM
authors: Froehlich
authors: Juerg
authors: J
authors: Hodler
authors: Dominik
authors: D
authors: Weishaupt
mesh_terms: D000293:Adolescent; D000328:Adult; D001175:Arthrography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006621:Hip Joint / Q000473:pathology*; D006801:Humans; D007270:Injections, Intra-Articular; D007592:Joint Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008536:Meglumine / Q000008:administration & dosage*; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage*; D011446:Prospective Studies; D012785:Shoulder Joint / Q000473:pathology*; D014955:Wrist Joint / Q000473:pathology*
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D008536:Meglumine; C072417:gadoterate meglumine