gms | German Medical Science

Objectives: To investigate the quantitative diagnosis value of MRI T1rho and T2 mapping imaging techniques in cartilage damage of osteonecrosis of femoral head, and to assess the potential correlation of T1rho and T2 mapping.

Methods: 63 ONFH specimens in 50 patients in Association of Research Circulation Osseous (ARCO) I-III and 38 healthy participants (control group) were undergoing conventional MRI, MERGE, T1rho and T2 mapping examinations. Median patient age was 43.5 years (range 36-50 years). Through the workstation post-processing, we calculate the quantitative parameters of T1rho and T2 mapping values. Finally, we evaluate the correlation between T1rho and T2 mapping by Person correlation and to investigate the advance diagnosis value of them by ROC curve.

Results and Conclusion: T1rho and T2 mapping values of ONFH group (T1rho: 50.98±13.23 and T2: 25.47±9.04, T: -4.51, P<0.01) are higher than the same values of the control group (T1rho: 38.22±5.65 and T2: 18.13±4.22, T: -3.77, P<0.01). The values of T1rho showed a positive correlation with T2 mapping (r=0.381, P<0.01). The cut off T1rho value was 0.822 (95%CI: 0.726-0.918), with a sensitivity of 72.34% and a specificity of 70.83%. The cut off T2 mapping value was 0.791 (95%CI: 0.687-0.895), with a sensitivity of 72.33% and a specificity of 58.33%. Overall, T1rho and T2 mapping were positively correlated and the diagnostic value of T1rho is better than T2 mapping. T1rho/T2 mapping MRI is the promising new technique which could potentially be used for accurate assessment of cartilage injury of ONFH in ARCO I-III stages in order to guide diagnosis and treatment. Future studies need to be carried out to see if this technology could have a role of necrotic tissue assessment.