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Comparison of 3D MR imaging sequences in knee articular cartilage at 1.5 T

Mokhtar Mars, Zeineb Tbini, Mouna Chelli, Fethi Ladeb

Purpose: To compare 3D high-resolution MRI sequences in term of contrast, Signal to Noise Ratio (SNR), artefacts and cartilage thickness in knee articular cartilage at 1.5 T.

Materials and Methods: Fourteen healthy volunteers and seven patients underwent articular knee cartilage exam. The 3D sequences were VOLUME Imaging with Body Enhancement (VIBE), True Fast Imaging with Steady-state Precession (TRUEFISP), Dual Echo Steady State (DESS), Multi Echo Data Image Combination (MEDIC) and Sampling Perfection with Application optimized Contrasts using different flip angle Evolutions (SPACE). For all 3D sequences, we measured contrast ratio between cartilage-bone and cartilage-meniscus, SNR and cartilage thickness. In addition, we quantified magnetic susceptibility and flow artifacts. Statistical analyses were performed using the t-test and P<0.005 was considered statistically significant.

Results: Statistical results were significantly different (p>0.05). MEDIC and VIBE sequences showed the best contrast ratio between cartilage-meniscus (0.40 ± 0.14, p=0.000) and cartilage-bone (0.75 ± 0.4, p=0.022), respectively. TRUEFISP sequence showed the highest SNR (28.04 ± 14.05, p=0.000) whereas DESS sequence showed the lowest SNR (11.62 ± 3.99, p=0.000). VIBE sequence provided the highest cartilage thickness measurement compared to the remaining 3D sequences (2.0 ± 0.4 cm, IRR=75.33%, ICC=0.96). The quantification of magnetic susceptibility and flow artifacts revealed that TRUEFISP (IRR=59%, ICC=0.92) and SPACE (IRR=59%, ICC=0.96) sequences presented the highest artifacts compared to the others sequences.

Conclusion: 3D high-resolution sequences provide knee articular cartilage imaging with high image quality in relatively short acquisition time. MEDIC and VIBE sequences showed the best contrast and the lowest magnetic susceptibility and flow artifacts, TRUEFISP and SPACE sequence showed the highest SNR but they are more sensitive to artifacts, DESS sequence showed medium contrast and VIBE sequence provided the highest cartilage thickness.