Advanced morphological 3D magnetic resonance observation of cartilage repair tissue (MOCART) scoring using a new isotropic 3D proton‐density, turbo spin echo sequence with variable flip angle distribution (PD‐SPACE) compared to an isotropic 3D steady‐state free precession sequence (True‐FISP) and standard 2D sequences

Abstract

Purpose: To evaluate a new isotropic 3D proton-density, turbo-spin-echo sequence with variable flip-angle distribution (PD-SPACE) sequence compared to an isotropic 3D true-fast-imaging with steady-state-precession (True-FISP) sequence and 2D standard MR sequences with regard to the new 3D magnetic resonance observation of cartilage repair tissue (MOCART) score. Materials and Methods:Sixty consecutive MR scans on 37 patients (age: 32.8 6 7.9 years) after matrix-associated autologous chondrocyte transplantation (MACT) of the knee were prospectively included. The 3D MOCART score was assessed using the standard 2D sequences and the multiplanar-reconstruction (MPR) of both isotropic sequences. Statistical, Bonferroni-corrected correlation as well as subjective quality analysis were performed.Results: The correlation of the different sequences was significant for the variables defect fill, cartilage interface, bone interface, surface, subchondral lamina, chondral osteophytes, and effusion (Pearson coefficients 0.514-0.865). Especially between the standard sequences and the 3D True-FISP sequence, the variables structure, signal intensity, subchondral bone, and bone marrow edema revealed lower, not significant, correlation values (0.242-0.383). Subjective quality was good for all sequences (P ! 0.05). Artifacts were most often visible on the 3D True-FISP sequence (P < 0.05).Conclusion: Different isotropic sequences can be used for the 3D evaluation of cartilage repair with the benefits of isotropic 3D MRI, MPR, and a significantly reduced scan time, where the 3D PD-SPACE sequence reveals the best results.

Comparison of Modern 3D and 2D MR Imaging Sequences of the Wrist at 3 Tesla

“…Also, TrueFISP was recommended for monitoring osteoarthritis disease progression at the knee, particularly due to the high SNR/ CNR values [16,17]. A regional decrease in image quality because of artifacts, as present in our patient group, was also reported in other studies [11,14,18]. Therefore, especially in the postoperative situation when susceptibility is expected, the use of TSE-instead of GRE-based sequences may be beneficial.…”

“…This in combination with its high resolution and isotropic voxels may facilitate the detection of cartilage defects, especially when regional cartilage integrity is crucial to decide between limited surgical procedures and total wrist arthrodesis [12,13]. TrueFISP has also proved advantages in cartilage imaging in other joints [14,15]. In a study of the knee joint [14], TrueFISP provided excellent image quality, reaching 3.78 ± 0.5 from a maximum of 4 points in 37 patients after matrixassociated autologous chondrocyte transplantation (MACT).…”

“…TrueFISP has also proved advantages in cartilage imaging in other joints [14,15]. In a study of the knee joint [14], TrueFISP provided excellent image quality, reaching 3.78 ± 0.5 from a maximum of 4 points in 37 patients after matrixassociated autologous chondrocyte transplantation (MACT). Also, TrueFISP was recommended for monitoring osteoarthritis disease progression at the knee, particularly due to the high SNR/ CNR values [16,17].…”

Comparison of 3D turbo spin-echo SPACE sequences with conventional 2D MRI sequences to assess the shoulder joint

“…Mohr et al [28] compared fat saturated 2D PD TSE sequences to water-excitation 3D fast low angle shot (WE 3D FLASH), but found the conventional 2D TSE to be superior to the 3D sequence. Welsch et al [12] compared 3D SPACE in PD-weighting, isotropic 3D true-fast-imaging with steady-stateprecession (True-FISP) and conventional 2D MR sequences in the observation of cartilage repair tissue in 37 patients. The authors reported the 3D SPACE sequences in PD weighting not only to be equivalent at reduced scan time, but also superior to the other imaging modalities.…”

“…Due to the recently developed MRI techniques and the increasing performance of workstations and Picture Archiving and Communication System (PACS) capabilities, the use of 3D sequences and their immediate post-processing, has become clinically feasible [9][10][11], for example in cartilage imaging of the kneeand ankle joint [12][13][14]. Therefore, the aim of this study was to determine the accuracy and reliability of 3D TSE proton-density (PD) weighted and T1-weighted sequences with applicationoptimized contrasts using different flip-angle evolution (SPACE, Siemens Healthcare, Erlangen, Germany) compared with conventional 2D TSE PD and T1-weighted sequences in the assessment of the shoulder joint.…”