Clinical and Translational Research
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Aug 26, 2020; 8(16): 3431-3439
Published online Aug 26, 2020. doi: 10.12998/wjcc.v8.i16.3431
Application of molybdenum target X-ray photography in imaging analysis of caudal intervertebral disc degeneration in rats
Qi-Hang Su, Yan Zhang, Bin Shen, Yong-Chao Li, Jun Tan
Qi-Hang Su, Yan Zhang, Bin Shen, Yong-Chao Li, Jun Tan, Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
Author contributions: Su QH designed the research and wrote the paper; Su QH, Zhang Y, Li YC and Shen B performed the research; Su QH and Zhang Y contributed new analytic tools; Su QH and Tan J analyzed the data.
Supported by the National Key Research and Development Program of China, No. 2017YFA0105404.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board at Shanghai East Hospital (East Hospital Affiliated to Tongji University) Medical Ethics Committee.
Institutional animal care and use committee statement: Shanghai East Hospital (East Hospital Affiliated to Tongji University) Medical Ethics Committee approved the study protocol, which met the relevant guidelines and regulations of Shanghai Medical Ethics Committee in accordance with internationally accepted principles for the use of laboratory animals.
Conflict-of-interest statement: The authors declare that they have no financial or other conflicts of interest in relation to this research and its publication.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Qi-Hang Su, MD, Doctor, Department of Orthopedics, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China. 15221378017@163.com
Received: April 30, 2020
Peer-review started: April 30, 2020
First decision: June 4, 2020
Revised: June 9, 2020
Accepted: July 17, 2020
Article in press: July 17, 2020
Published online: August 26, 2020
Abstract
BACKGROUND

Conventional plain X-ray images of rats, the most common animals used as degeneration models, exhibit unclear vertebral structure and blurry intervertebral disc spaces due to their small size, slender vertebral bodies.

AIM

To apply molybdenum target X-ray photography in the evaluation of caudal intervertebral disc (IVD) degeneration in rat models.

METHODS

Two types of rat caudal IVD degeneration models (needle-punctured model and endplate-destructed model) were established, and their effectiveness was verified using nuclear magnetic resonance imaging. Molybdenum target inspection and routine plain X-ray were then performed on these models. Additionally, four observers were assigned to measure the intervertebral height of degenerated segments on molybdenum target plain X-ray images and routine plain X-ray images, respectively. The degeneration was evaluated and statistical analysis was subsequently conducted.

RESULTS

Nine rats in the needle-punctured model and 10 rats in the endplate-destructed model were effective. Compared with routine plain X-ray images, molybdenum target plain X-ray images showed higher clarity, stronger contrast, as well as clearer and more accurate structural development. The McNemar test confirmed that the difference was statistically significant (P = 0.031). In the two models, the reliability of the intervertebral height measured by the four observers on routine plain X-ray images was poor (ICC < 0.4), while the data obtained from the molybdenum target plain X-ray images were more reliable.

CONCLUSION

Molybdenum target inspection can obtain clearer images and display fine calcification in the imaging evaluation of caudal IVD degeneration in rats, thus ensuring a more accurate evaluation of degeneration.

Keywords: Molybdenum target inspection, Routine plain X-ray, Intervertebral disc degeneration model, Animal experiment, Imaging analysis, McNemar test

Core tip: Imaging evaluation is a crucial, easy to use, low-cost and effective technique, especially for evaluating intervertebral disc space height, and is the most commonly used quantitative indicator of intervertebral disc degeneration in animal models. However, in rats with small vertebral bodies and narrow intervertebral disc spaces, conventional plain X-ray images have poor definition and low contrast, micro-calcifications are unclear, and the imaging effect on the boundary of the narrow intervertebral disc space is poor. This is the first study to apply molybdenum target X-ray photography to the imaging evaluation of caudal intervertebral disc degeneration in rat models.