Cruciate ligament injuries of the knee: A meta-analysis of the diagnostic performance of 3D MRI

BACKGROUND: Despite the advantages of 3D MRI in evaluation of cruciate ligament injuries, its use in clinical practice is still a matter of debate due to controversy regarding its diagnostic performance. PURPOSE: To evaluate the diagnostic performance of 3D MRI for detecting cruciate ligament injuries, using surgery or arthroscopy as the reference standard. STUDY TYPE: Meta-analysis. POPULATION: Patients with knee pain. FIELD STRENGTH/SEQUENCE: 3D and 2D MRI. ASSESSMENT: Four databases were reviewed according to PRISMA guidelines. STATISTICAL TESTS: Pooled values of sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated using a random-effects model. To investigate the effect of relevant covariates on the diagnostic performance of 3D MRI, sensitivity analysis was performed using meta-regression to calculate relative DOR. RESULTS: Of 731 initially identified reports, 22 (1298 3D MRI examinations) met our criteria and were included. Pooled estimates of sensitivity and specificity for 3D sequences were 91.4% (95% confidence interval [CI]: 87.4-94.2%) and 96.1% (95% CI: 93.8-97.6%), respectively. Fourteen studies also reported the results of 2D MRI, with pooled sensitivity of 90.6% (95% CI: 84.1-94.6%) and specificity of 97.1% (95% CI: 94.7-98.4%), which were not significantly different from 3D sequences. 3D MRI sequences performed using 3T scanners had significantly higher DOR compared with 3D sequences performed on 1.5T or lower scanners (relative DOR: 6.04, P = 0.01). DATA CONCLUSION: 3D MRI is equivalent to 2D MRI in the diagnosis of cruciate ligament injuries. The use of 3T scanners improves the performance of 3D MRI for detecting cruciate ligament injuries. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1545-1560.