Novel MR imaging method--MAVRIC--for metal artifact suppression after joint replacement in musculoskeletal tumor
Michiro Susa1,2, Sota Oguro3, Kazutaka Kikuta4
1Department of Orthopaedic Surgery, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan. mitchsusa@gmail.com.
Background:
Standard imaging modality for the follow-up after prosthetic replacements for musculoskeletal tumor patients has been conventional radiography. This technique is effective in detecting subtle changes in bone adjacent to metal implants, but in many cases, radiographs do not lead to definitive diagnosis of postoperative adverse events such as acute infection, local recurrence of soft tissue tumor or soft tissue local recurrence of osseous sarcoma. Conventional MRI sequences have not been effective due to metal artifacts. In this study, we tried to elucidate the effectiveness of metal artifact suppression using novel sequence, multiacquisition variable-resonance image combination (MAVRIC), after musculoskeletal tumor surgeries.
Methods:
We retrospectively analyzed 5 cases of malignant bone and soft tissue sarcoma patients who were reconstructed with metal prosthesis after wide resection of tumors. Images obtained using MAVRIC and short tau inversion recovery (STIR) were compared side by side. The paired MAVRIC and STIR images were qualitatively compared independently by two specialists for 4 parameters: visualization of bone - implant interface, visualization of surrounding soft tissues, image blurring, and overall image quality. Quantitatively, paired images were reviewed to identify the slice where the metal artifact was maximal, and a region of interest encompassing the implant and surrounding artifact was drawn using Advantage Workstation (GE Healthcare, Japan).
Results:
There were no local recurrences that were detected. By utilizing MAVRIC, visualization of the bone - implant interface and visualization of the surrounding soft tissue were significantly improved in MAVRIC compared to STIR. Although blurring was worse on the MAVRIC acquisitions, the overall image quality was still better on MAVRIC. Quantitatively, the area of metal artifact measured using MAVRIC was markedly less compared to STIR (61.4 cm(2) vs 135.9 cm(2)).
Conclusion:
Despite the relatively small number of cases in the present study, our observation strongly suggests that MAVRIC is able to improve the quality of images by decreasing the artifact caused by endoprosthesis, frequently utilized in reconstruction of musculoskeletal tumor patients. Further installments of conventional imaging sequences with the addition of gadolinium - enhancement will enable increased accuracy in diagnosing local recurrences of sarcoma patients.
Insights
The novel MAVRIC sequence significantly reduces metal artifacts in MRI scans for musculoskeletal tumor patients with prostheses. This improved imaging quality aids in better visualization of the bone-implant interface and surrounding tissues.
Area of Science:
- Orthopedic Oncology
- Radiology
- Medical Imaging
Background:
- Conventional radiography is standard for follow-up after musculoskeletal tumor surgery but struggles with diagnosing complications.
- Conventional MRI sequences are limited by metal artifacts, hindering visualization of critical structures.
- Postoperative adverse events like infection or tumor recurrence require advanced imaging techniques.
Purpose of the Study:
- To evaluate the effectiveness of the multi-acquisition variable-resonance image combination (MAVRIC) sequence for metal artifact reduction.
- To compare MAVRIC with conventional STIR sequences in patients with musculoskeletal tumor prostheses.
- To assess the impact of MAVRIC on the visualization of the bone-implant interface and surrounding soft tissues.
Main Methods:
- Retrospective analysis of 5 sarcoma patients with metal prostheses.
- Side-by-side comparison of MAVRIC and STIR MRI sequences.
- Qualitative assessment by two specialists for image quality parameters.
- Quantitative measurement of metal artifact area.
Main Results:
- MAVRIC significantly improved visualization of the bone-implant interface and surrounding soft tissues compared to STIR.
- Overall image quality was superior with MAVRIC, despite slightly worse blurring.
- The metal artifact area was markedly reduced with MAVRIC (61.4 cm²) compared to STIR (135.9 cm²).
Conclusions:
- MAVRIC effectively reduces endoprosthesis-induced artifacts in musculoskeletal tumor patients.
- Improved image quality with MAVRIC facilitates better assessment of the surgical site.
- Future studies incorporating gadolinium enhancement with MAVRIC may further enhance diagnostic accuracy for tumor recurrence.
Related Concept Videos
01:24Magnetic Resonance Imaging
01:30Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
01:27Imaging Studies IV: Magnetic Resonance Imaging
01:21Imaging Studies for Cardiovascular System IV: CMRI
01:27Imaging Studies III: Computed Tomography
01:14Imaging Studies I: CT and MRI
Description of the Procedures
Computed Tomography (CT) scan:
Computed Tomography (CT) scans use X-ray technology to generate detailed images of bones, organs, and tissues. During the scan, the patient lies on a moving table...