ABSTRACT
Objective:To explore the clinical application value of MRI in quantitative evaluation of anterior cruciate ligament mucoid degeneration (ACL-MD).Methods:From March to July 2020, 40 patients who were scheduled to undergo arthroscopic treatment were prospectively collected in the First Affiliated Hospital of Kunming Medical University.The anterior cruciate ligament tissue from the lateral edge of the tibial end was taken during the operation. Based on the pathologicalre sults, the patients were divided into the ACL-MD group ( n=19) and the normal group ( n=21). The sagittal plane three-dimensional steady-state rapid precession (3D-FIESTA), T 1 mapping, T 2 mapping, and T 2* mapping were performed before the knee joint surgery, and the scanned images were post-processed and analyzed to measure the T 1, T 2, and T 2* values of the tibial end of the anterior cruciate ligament.The relaxation time of the ACL-MD group and the normal group was compared using independent sample t test. The ROC curve was drawn using each parameter and the areas under the curve (AUC) for the diagnosis of ACL-MD were obtained.DeLong test was used to compare the differences of AUCs. Results:The T 1 [(1 291.9±273.4) ms], T 2 [(54.8±10.6) ms], and T 2* values [(30.6±6.4) ms] of anterior cruciate ligaments in the ACL-MD group were significantly higher than those in the normal group [ (1 087.0±121.0), (44.8±7.1), (20.4±4.8) ms; t=3.011, 3.473, 5.658, all P<0.001]. The AUCs of T 1, T 2, T 2* were 0.747, 0.764, 0.912, sensitivity of 63.2%, 63.2%, 100%, and the specificity of 100%, 95.2%, 76.2% in diagnosing ACL-MD. The AUC of the T 2* value was higher than those of the T 1 and T 2 values, and the differences were statistically significant ( Z=1.734, 2.162, P=0.043, 0.031). Conclusion:T 1, T 2, T 2*values measured by MRI quantitative imaging have high performance in assessing knee joint ACL-MD, and T 2* value has the largest AUC and the highest diagnostic efficiency.