title: Contrast-enhanced MRI of the knee in children unaffected by clinical arthritis compared to clinically active juvenile idiopathic arthritis patients.
abstract: OBJECTIVE
  To evaluate enhancing synovial thickness upon contrast-enhanced magnetic resonance imaging (MRI) of the knee in children unaffected by clinical arthritis compared with clinically active juvenile idiopathic arthritis (JIA) patients. A secondary objective was optimization of the scoring method based on maximizing differences on MRI between these groups.
  
  
  METHODS
  Twenty-five children without history of joint complaints nor any clinical signs of joint inflammation were age/sex-matched with 25 clinically active JIA patients with arthritis of at least one knee. Two trained radiologists, blinded for clinical status, independently evaluated location and extent of enhancing synovial thickness with the validated Juvenile Arthritis MRI Scoring system (JAMRIS) on contrast-enhanced axial fat-saturated T1-weighted MRI of the knee.
  
  
  RESULTS
  Enhancing synovium (≥2 mm) was present in 13 (52 %) unaffected children. Using the total JAMRIS score for synovial thickening, no significant difference was found between unaffected children and active JIA patients (p = 0.091). Additional weighting of synovial thickening at the JIA-specific locations enabled more sensitive discrimination (p = 0.011).
  
  
  CONCLUSIONS
  Mild synovial thickening is commonly present in the knee of children unaffected by clinical arthritis. The infrapatellar and cruciate ligament synovial involvement were specific for JIA, which-in a revised JAMRIS-increases the ability to discriminate between JIA and unaffected children.
  
  
  CONCLUSIONS
  • Synovial inflammation is the primary disease feature in juvenile idiopathic arthritis (JIA). • Appearance of the synovium on contrast-enhanced MRI in unaffected children is unknown. • Validation of existing scoring methods requires comparison between JIA and unaffected children. • Mild enhancing synovial thickening was detected in half of the unaffected children. • Location-weighting for JIA-specific locations increased discriminative value of the scoring methods (p = 0.011).
authors.affiliation: Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands. c.m.nusman@amc.nl.|Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands. c.m.nusman@amc.nl.
authors.forename: Charlotte M
authors.initials: CM
authors.lastname: Nusman
authors.affiliation: Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.|Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Robert
authors.initials: R
authors.lastname: Hemke
authors.affiliation: Department of Pediatric Gastroenterology, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Benninga
authors.affiliation: Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Dieneke
authors.initials: D
authors.lastname: Schonenberg-Meinema
authors.affiliation: Department of Pediatric Gastroenterology, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Angelika
authors.initials: A
authors.lastname: Kindermann
authors.affiliation: Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.|Department of Pediatric Rheumatology, Reade, Dr. Jan van Breemenstraat 2, Amsterdam, The Netherlands.
authors.forename: Marion A J
authors.initials: MA
authors.lastname: van Rossum
authors.affiliation: Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: J Merlijn
authors.initials: JM
authors.lastname: van den Berg
authors.affiliation: Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
authors.forename: Mario
authors.initials: M
authors.lastname: Maas
authors.affiliation: Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital AMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Taco W
authors.initials: TW
authors.lastname: Kuijpers
mesh_terms: D000293:Adolescent; D001171:Arthritis, Juvenile / Q000473:pathology*; D015331:Cohort Studies; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement; D007719:Knee Joint / Q000033:anatomy & histology / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies
chemical_list: D003287:Contrast Media
keywords: Control group; Juvenile idiopathic arthritis; Knee; Magnetic resonance imaging; Synovium