Tuomas Svrd1, Tomos G. Williams2,
Eveliina Lammentausta1, Yang Xia3, Miika T. Nieminen4
1Department of Diagnostic Radiology,
Oulu University Hospital, Oulu, Finland; 2School of Cancer,
Enabling Science and Technology, The University of Manchester, United
Kingdom; 3Department of Physics and Center for Biomedical
Research, Oakland University, Rochester, MI, United States; 4Department
of Medical Technology, University of Oulu, Oulu, Finland
T2
relaxation time in articular cartilage could provide an early biomarker of
cartilage quality in disease. T2 measures are dependent on the orientation of
collagen fibrils with respect to the B0 field. Variation in joint positioning
has a detrimental effect on the reproducibility of T2. In a study of three
volunteers, imaged five times each, the variation in orientation of
load-bearing femoral joint surfaces was determined using an Active Appearance
Model of the distal femur bone. Simulations revealed that the variation in T2
due to joint positioning is acceptable (0.1-4.7ms) compared to the expected
elevation related to pathological changes.