Objective To study the application value of magnetic resonance (MR) imaging of three dimensional water selective excitation (3D-WATS) in cartilage injury of knee joint. MethodsA total of 60 patients with confirmed cartilage injury of knee joint in our hospital between January and November 2019 were recruited in this study. They all underwent MR imaging

including T1WI

T2WI

PDWI

T2-mapping

and 3D-WATS sequences. With the results of arthroscopy as the diagnostic standard

the diagnostic efficacy of PDWI

T2-mapping and 3D-WATS for cartilage injury were compared with Chi-square test

and staging coincidence was studied with Spearman correlation analysis. ResultsThe diagnostic efficacy of PDWI

T2-mapping and 3D-WATS sequences statistically differed from each other in knee cartilage injury (AUC=0.842

0.934 and 0.974; P=0.000). Compared with the results of arthroscopy

the 3D-WATS sequence revealed cartilage injury in 58 cases

and the consistency of staging was good with the results of arthroscopy (rho=1.00

P=0.00). T2-mapping sequence found cartilage injury in 53 cases

and took the second in consistency of staging (rho=0.80

P=0.20). PDWI sequence revealed cartilage injury in 51 cases

with poor staging with the results of arthroscopy (rho=0.20

P=0.80)

and more minor injuries were missed. Conclusion3D-WATS sequence has good diagnostic efficacy and consistency of staging for cartilage injury

and can be used as a routine sequence of MRI knee imaging.