Purpose: To compare magnetic resonance imaging of the ankle joint at 1.5 Tesla (T) and 3.0 T in the assessment of cartilage and ligament pathology in fresh human cadaver specimens.
Materials and methods: The study was performed in line with institutional and legislative requirements; all donors had dedicated their body for educational and research purposes before death. Thirteen fresh human cadaver ankle joints were imaged at 1.5 T and 3.0 T using an optimized clinical ankle protocol consisting of T1-weighted (T1-w), fat-saturated (fs) T2-w, and short tau inversion recovery fast spinecho (FSE) sequences. For dedicated cartilage imaging, fs-intermediate (IM)-w FSE, fs-spoiled gradient echo, and balanced free precession steady state sequences were acquired. Artificial cartilage and ligament lesions were created in 6 and 5 specimens, respectively. MR imaging was repeated in those ankles. Four radiologists independently assessed pathology in all image datasets. Macroscopic findings after dissection served as a reference standard.
Results: Sensitivities and ROC-values were higher at 3.0 T for detecting cartilage pathology (sensitivity up to 0.71 at 3.0 T vs. 0.49 at 1.5 T; AZ up to 0.88 vs. 0.74; both differences P < 0.05) and highest for the fs-IM FSE sequence at 3.0 T. Average sensitivity for detecting ligament pathology was higher at 3.0 T (0.69 vs. 0.50; P < 0.05). Specificity was high among all protocols and both field strengths for assessing ligament and cartilage pathology (>0.95).
Conclusion: Compared with 1.5-T imaging, the 3.0-T imaging of the ankle joint at improved diagnostic performance in assessing cartilage significantly and there was a higher sensitivity for assessing ligamentous pathology.