Author:
Liu Di,Hu Ping,Cai Zi-Jun,Lu Wen-Hao,Pan Lin-Yuan,Liu Xu,Peng Xian-Jing,Li Yu-Sheng,Xiao Wen-Feng
Abstract
Abstract
Objectives
To determine whether dual-energy CT (DECT) can be used to accurately and reliably detect anterior cruciate ligament (ACL) rupture.
Materials and methods
Participants with unilateral ACL rupture were prospectively enrolled, and the bilateral knees were scanned by DECT. A tissue-specific mapping algorithm was applied to improve the visualization of the ACLs. The 80-keV CT value, mixed-keV CT value, electron density (Rho), and effective atomic number (Zeff) were measured to quantitatively differentiate torn ACLs from normal ACLs. MRI and arthroscopy served as the reference standards.
Results
Fifty-one participants (mean age, 27.0 ± 8.7 years; 31 men) were enrolled. Intact and torn ACLs were explicitly differentiated on color-coded DECT images. The 80-keV CT value, mixed-keV CT value, and Rho were significantly lower for the torn ACLs than for the intact ACLs (p < 0.001). The optimal cutoff values were an 80-keV CT value of 61.8 HU, a mixed-keV CT value of 60.9 HU, and a Rho of 51.8 HU, with AUCs of 98.0% (95% CI: 97.0–98.9%), 99.2% (95% CI: 98.6–99.7%), and 99.8% (95% CI: 99.6–100.0%), respectively. Overall, DECT had almost perfect reliability and validity in detecting ACL integrity (sensitivity = 97.1% [95% CI: 88.1–99.8%]; specificity = 98.0% [95% CI: 89.5–99.9%]; PPV = 98.0% [95% CI: 93.0–99.8%]; NPV = 97.1% [95% CI: 91.7–99.4%]; accuracy = 97.5% [95% CI: 94.3–99.2%]). There was no evidence of a difference between MRI and DECT in the diagnostic performance (p > 0.99).
Conclusion
DECT has excellent diagnostic accuracy and reliability in qualitatively and quantitatively diagnosing ACL rupture.
Clinical relevance statement
DECT could validly and reliably diagnose ACL rupture using both qualitative and quantitative methods, which may become a promising substitute for MRI to evaluate the integrity of injured ACLs and the maturity of postoperative ACL autografts.
Key Points
• On color-coded DECT images, an uncolored ACL was a reliable sign for qualitatively diagnosing ACL rupture.
• The 80-keV CT value, mixed-keV CT value, and Rho were significantly lower for the torn ACLs than for the intact ACLs, which contributed to the quantitative diagnosis of ACL rupture.
• DECT had an almost perfect diagnostic performance for ACL rupture, and diagnostic capability was comparable between MRI and DECT.
Funder
National Key R&D Program of China
National Natural Science Foundation of China
Provincial Clinical Medical Technology Innovation Project of Hunan
National Clinical Research Center for Geriatric Disorders
National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation
Innovation-Driven Project of Central South University
Wu Jieping Medical Foundation
CMA▪Young and Middle-aged Doctors Outstanding Development Program-Osteoporosis Specialized Scientific Research Fund Project
Key Program of Health Commission of Hunan Province
Fundamental Research Funds for the Central Universities of Central South University
Publisher
Springer Science and Business Media LLC
Subject
Radiology, Nuclear Medicine and imaging,General Medicine