title: MRI after arthroplasty: comparison of MAVRIC and conventional fast spin-echo techniques.
abstract: OBJECTIVE
  The goal of this study was to evaluate the quality of images obtained with a prototype imaging technique, multiacquisition variable-resonance image combination (MAVRIC), compared with fast spin-echo (FSE) images in the evaluation of patients who have undergone hip, shoulder, or knee arthroplasty.
  
  
  METHODS
  MRI with metal-artifact reduction FSE and MAVRIC sequences was performed in the care of 122 patients who had undergone 74 hip, 27 shoulder, and 21 knee arthroplasties. The FSE and MAVRIC images were subjectively graded for visualization of the synovium, prosthesis-bone interface, and hip abductors or supraspinatus tendon. The presence of synovitis, osteolysis, or supraspinatus tendon tear was recorded.
  
  
  RESULTS
  Visualization of the synovium was significantly better on MAVRIC images than on FSE images of the hip (p < 0.0001), shoulder (p < 0.01), and knee (p < 0.01). Synovitis was detected only on the MAVRIC images of nine subjects (12%) who had undergone hip arthroplasty and five subjects (18%) who had undergone shoulder arthroplasty. Visualization of the periprosthetic bone was significantly better on MAVRIC images of the hip (p < 0.0001), shoulder (p < 0.0001), and knee (p < 0.01). Osteolysis was detected only on the MAVRIC images of 12 subjects (16%) who had undergone hip arthroplasty, six (22%) who had undergone shoulder arthroplasty, and five (24%) who had undergone knee arthroplasty. Visualization of the supraspinatus tendon was significantly better on MAVRIC images (p < 0.0001). Supraspinatus tendon tears in 12 subjects (44%) were detected only on MAVRIC images.
  
  
  CONCLUSIONS
  MAVRIC complements the information on FSE images after arthroplasty and is a useful additional sequence, particularly when there is concern about synovitis, periprosthetic osteolysis, or the presence of a supraspinatus tendon tear.
authors.affiliation: Department of Radiology and Imaging, Hospital for Special Surgery, 535 E 70th St, New York, NY 10021, USA.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Hayter
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Koff
authors.forename: Parina
authors.initials: P
authors.lastname: Shah
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Koch
authors.forename: Theodore T
authors.initials: TT
authors.lastname: Miller
authors.forename: Hollis G
authors.initials: HG
authors.lastname: Potter
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement; D016477:Artifacts; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008670:Metals; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis*; D018709:Statistics, Nonparametric
chemical_list: D008670:Metals