title: Automated analysis of hip joint cartilage combining MR T2 and three-dimensional fast-spin-echo images.
abstract: OBJECTIVE
  To validate a fully automated scheme to extract biochemical information from the hip joint cartilages using MR T2 mapping images incorporating segmentation of co-registered three-dimensional Fast-Spin-Echo (3D-SPACE) images.
  
  
  METHODS
  Manual analyses of unilateral hip (3 Tesla) MR images of 24 asymptomatic volunteers were used to validate a 3D deformable model method for automated cartilage segmentation of SPACE scans, partitioning of the individual femoral and acetabular cartilage plates into clinically defined sub-regions and propagating these results to T2 maps to calculate region-wise T2 value statistics. Analyses were completed on a desktop computer (∼ 10 min per case).
  
  
  RESULTS
  The mean voxel overlap between automated A and manual M segmentations of the cartilage volumes in the (clinically based) SPACE images was 73% (100 × 2|A∩M|/[|A|+|M|]). The automated and manual analyses demonstrated a relative difference error <10% in the median "T2 average signal" for each cartilage plate. The automated and manual analyses showed consistent patterns between significant differences in T2 data across the hip cartilage sub-regions.
  
  
  CONCLUSIONS
  The good agreement between the manual and automatic analyses of T2 values indicates the use of structural 3D-SPACE MR images with the proposed method provides a promising approach for automated quantitative T2 assessment of hip joint cartilages.
authors: School of Information Technology and Electrical Engineering, University of Queensland, Australia.
authors: Shekhar S
authors: SS
authors: Chandra
authors: Steadman Philippon Research Institute (SPRI), Colorado, USA.
authors: Rachel
authors: R
authors: Surowiec
authors: Steadman Philippon Research Institute (SPRI), Colorado, USA.
authors: Charles
authors: C
authors: Ho
authors: School of Information Technology and Electrical Engineering, University of Queensland, Australia.|Australian e-Health Research Centre, CSIRO Computational Informatics, Australia.
authors: Ying
authors: Y
authors: Xia
authors: School of Human Movement Studies, University of Queensland, Australia.
authors: Craig
authors: C
authors: Engstrom
authors: School of Information Technology and Electrical Engineering, University of Queensland, Australia.
authors: Stuart
authors: S
authors: Crozier
authors: Australian e-Health Research Centre, CSIRO Computational Informatics, Australia.
authors: Jurgen
authors: J
authors: Fripp
mesh_terms: D000328:Adult; D000465:Algorithms; D002358:Cartilage, Articular / Q000033:anatomy & histology*; D017352:Echo-Planar Imaging / Q000379:methods*; D005260:Female; D006621:Hip Joint / Q000033:anatomy & histology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D055815:Young Adult
keywords: 3D-SPACE; Active Shape Models; Graph-Cuts; Hip; T2 mapping