title: Quantitative versus semiquantitative MR imaging of cartilage in blood-induced arthritic ankles: preliminary findings.
abstract: BACKGROUND
  Recent advances in hemophilia prophylaxis have raised the need for accurate noninvasive methods for assessment of early cartilage damage in maturing joints to guide initiation of prophylaxis. Such methods can either be semiquantitative or quantitative. Whereas semiquantitative scores are less time-consuming to be performed than quantitative methods, they are prone to subjective interpretation.
  
  
  OBJECTIVE
  To test the feasibility of a manual segmentation and a quantitative methodology for cross-sectional evaluation of articular cartilage status in growing ankles of children with blood-induced arthritis, as compared with a semiquantitative scoring system and clinical-radiographic constructs.
  
  
  METHODS
  Twelve boys, 11 with hemophilia (A, n = 9; B, n = 2) and 1 with von Willebrand disease (median age: 13; range: 6-17), underwent physical examination and MRI at 1.5 T. Two radiologists semiquantitatively scored the MRIs for cartilage pathology (surface erosions, cartilage loss) with blinding to clinical information. An experienced operator applied a validated quantitative 3-D MRI method to determine the percentage area of denuded bone (dAB) and the cartilage thickness (ThCtAB) in the joints' MRIs. Quantitative and semiquantitative MRI methods and clinical-radiographic constructs (Hemophilia Joint Health Score [HJHS], Pettersson radiograph scores) were compared.
  
  
  RESULTS
  Moderate correlations were noted between erosions and dAB (r = 0.62, P = 0.03) in the talus but not in the distal tibia (P > 0.05). Whereas substantial to high correlations (r range: 0.70-0.94, P < 0.05) were observed between erosions, cartilage loss, HJHS and Pettersson scores both at the distal tibia and talus levels, moderate/borderline substantial (r range: 0.55-0.61, P < 0.05) correlations were noted between dAB/ThCtAB and clinical-radiographic constructs.
  
  
  CONCLUSIONS
  Whereas the semiquantitative method of assessing cartilage status is closely associated with clinical-radiographic scores in cross-sectional studies of blood-induced arthropathy, quantitative measures provide independent information and are therefore less applicable for that research design.
authors: Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, Canada, M5G1X8, andrea.doria@sickkids.ca.
authors: Andrea S
authors: AS
authors: Doria
authors: Ningning
authors: N
authors: Zhang
authors: Bjorn
authors: B
authors: Lundin
authors: Pamela
authors: P
authors: Hilliard
authors: Carina
authors: C
authors: Man
authors: Ruth
authors: R
authors: Weiss
authors: Gary
authors: G
authors: Detzler
authors: Victor
authors: V
authors: Blanchette
authors: Rahim
authors: R
authors: Moineddin
authors: Felix
authors: F
authors: Eckstein
authors: Marshall S
authors: MS
authors: Sussman
mesh_terms: D000293:Adolescent; D000465:Algorithms; D000843:Ankle Joint / Q000502:physiology*; D001168:Arthritis / Q000209:etiology* / Q000473:pathology*; D002358:Cartilage, Articular / Q000473:pathology*; D002648:Child; D006467:Hemophilia A / Q000150:complications* / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010363:Pattern Recognition, Automated / Q000379:methods; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity