Clinical Trials Study
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Mar 18, 2025; 16(3): 103169
Published online Mar 18, 2025. doi: 10.5312/wjo.v16.i3.103169
Role of WARP sequence magnetic resonance imaging with the removal of metal artifacts in the evaluation of lumbar adjacent
Wei Xu, Meng-Yun Xiong, Yi Wang, Qi-Feng Yu, Xiao-Jian Ye, Si-Lian Wang, Zhi-Kun Li
Wei Xu, Yi Wang, Qi-Feng Yu, Xiao-Jian Ye, Zhi-Kun Li, Department of Orthopedics, Shanghai Tongren Hospital, Shanghai 200336, China
Meng-Yun Xiong, Si-Lian Wang, Department of Imaging, Shanghai Tongren Hospital, Shanghai 200336, China
Co-first authors: Wei Xu and Meng-Yun Xiong.
Co-corresponding authors: Si-Lian Wang and Zhi-Kun Li.
Author contributions: Xu W, Wang SL, Xiong MY, Wang Y, Yu QF, Ye XJ and Li ZK designed the research study; Xu W, Wang SL, Xiong MY and Li ZK performed the research; Wang SL and Xiong MY performed magnetic resonance imaging (MRI); Li ZK, Wang Y, Yu QF and Ye XJ analyzed the data and wrote the manuscript. All authors have read and approve the final manuscript. Xu W and Xiong MY are co-first authors. This paper has two corresponding authors because it involves two professional fields: Spinal Surgery and Radiology. The two corresponding authors are from these two departments respectively. This paper requires the professional knowledge of both Spinal Surgery and Radiology. The expert in Spinal Surgery is responsible for the collection of clinical data, the diagnosis of adjacent segment disease patients and case analysis. The expert in Radiology is responsible for the parameter setting of artifact-removed MRI and the measurement of imaging parameters. Their joint participation ensures the comprehensiveness and scientificity of this study. Therefore, Wang SL and Li ZK are listed as co-corresponding authors.
Supported by Shanghai Tongren Hospital Scientific Research Funds, No. TRKYRC-xx202203; Shanghai Municipal Health Commission, No. 2022YQ006; and Science and Technology Commission of Shanghai Municipality, No. 22ZR1457200.
Institutional review board statement: This study was approved by the Ethics Committee of Shanghai Tongren Hospital.
Clinical trial registration statement: This study is registered at https://www.medicalresearch.org.cn/clinicalResearch/researchInfo?id=9db16381-5596-4215-a7fa-76a968c067eb. The registration identification number is [2024-08-28].
Informed consent statement: All study participants or their legal guardian provided informed written consent about personal and medical data collection prior to study enrolment.
Conflict-of-interest statement: The authors declare that they have no competing financial interests.
CONSORT 2010 statement: The authors have read the CONSORT 2010 Statement, and the manuscript was prepared and revised according to the CONSORT 2010 Statement.
Data sharing statement: Data not available to be shared.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Zhi-Kun Li, MD, Assistant Professor, Department of Orthopedics, Shanghai Tongren Hospital, No. 1111 Xianxia Road, Shanghai 200336, China. lizhikun@shsmu.edu.cn
Received: November 11, 2024
Revised: January 25, 2025
Accepted: February 20, 2025
Published online: March 18, 2025
Processing time: 121 Days and 15.1 Hours
Abstract
BACKGROUND

Posterior lumbar interbody fusion has good clinical results, but adjacent segment disease (ASD) affects its long-term efficacy. In patients with L4-5 fusion who were followed up for more than 10 years, the ASD incidence was 33.3%. Magnetic resonance imaging (MRI) is key for ASD diagnosis, but metal artifacts from internal fixation limit its use; therefore, removing the artifacts is crucial for ASD diagnosis and treatment.

AIM

To evaluate the value of WARP MRI for patients with lumbar ASD.

METHODS

In our hospital, the lumbar spines of patients with ASD were assessed via lumbar MRI, including conventional sequences and sequences for artifacts. A PACS workstation was used for image measurement, analysis, and assessment, which mainly included measurement of the internal fixation implant artifact area, evaluation of the visibility of the anatomical structures surrounding the implant, and diagnostic assessment of ASD in the section. Conventional MRI data sequences and artifacts to sequence the contrast analysis of the MRI data.

RESULTS

A total of 30 patients with ASD after lumbar fusion and internal fixation were included in the study; the patients included 13 male and 17 female patients and were aged 66.03 ± 5.83 years. The metal artifact area of the WARP T2-tirm sequence was significantly smaller than that of the conventional STIR sequence [(20.85 ± 6.27) cm² vs (50.56 ± 8.55) cm², P < 0.01]. The WARP T2-tirm sequence was observed around the implants, pedicles, intervertebral foramen, and vertebral bodies, and the conventional STIR sequence clearly displayed nerve roots within the intervertebral foramen. In all 30 patients, all adjacent segments of the WARP T2-tirm sequence could be clearly observed (above Grade 4), whereas it was difficult to observe these segments in the conventional STIR sequence due to the presence of more severe metal artifacts.

CONCLUSION

WARP sequences can significantly reduce the artifact area in the sagittal and cross-sectional images of titanium alloy spinal fixation, providing a good imaging reference for the diagnosis of ASD.

Keywords: Adjacent segment disease; Metal artifact; Metal artifact; Magnetic resonance

Core Tip: WARP magnetic resonance sequences can significantly reduce the artifact area in the sagittal and cross-sectional planes of titanium alloy spinal fixation, and the advantage of eliminating artifacts in the sagittal plane is more obvious. The resolution of the vertebral body, pedicle, intervertebral foramen, nerve root canal and herniated nucleus pulposus was significantly improved, which made the structures in the intervertebral space of the adjacent vertebrae clearly visible, providing a good imaging reference for the diagnosis of adjacent segment disease.