Five‐minute knee MRI for simultaneous morphometry and T2 relaxometry of cartilage and meniscus and for semiquantitative radiological assessment using double‐echo in steady‐state at 3T

• Published in: Journal of magnetic resonance imaging 2018-05, Vol.47 (5), p.1328-1341
• Main Authors: Chaudhari, Akshay S., Black, Marianne S., Eijgenraam, Susanne, Wirth, Wolfgang, Maschek, Susanne, Sveinsson, Bragi, Eckstein, Felix, Oei, Edwin H.G., Gold, Garry E., Hargreaves, Brian A.
• Format: Article
• Language: English
• Subjects: Agreements; Arthritis; Biocompatibility; Biomarkers; Biomedical materials; Bone marrow; Cartilage; Cartilage diseases; Coefficient of variation; Confidence intervals; Cysts; DESS; Field strength; Knee; Lesions; Magnetic resonance imaging; Mathematical analysis; Meniscus; MOAKS; Morphometry; Osteoarthritis; Osteophytes; Rank tests; Reproducibility; Sensitivity analysis; Statistical analysis; Statistical tests
• ISSN: 1053-1807; 1522-2586
• DOI: 10.1002/jmri.25883

Background Biomarkers for assessing osteoarthritis activity necessitate multiple MRI sequences with long acquisition times. Purpose To perform 5‐minute simultaneous morphometry (thickness/volume measurements) and T2 relaxometry of both cartilage and meniscus, and semiquantitative MRI Osteoarthritis Knee Scoring (MOAKS). Study Type Prospective. Subjects Fifteen healthy volunteers for morphometry and T2 measurements, and 15 patients (five each Kellgren–Lawrence grades 0/2/3) for MOAKS assessment. Field Strength/Sequence A 5‐minute double‐echo steady‐state (DESS) sequence was evaluated for generating quantitative and semiquantitative osteoarthritis biomarkers at 3T. Assessment Flip angle simulations evaluated tissue signals and sensitivity of T2 measurements. Morphometry and T2 reproducibility was compared against morphometry‐optimized and relaxometry‐optimized sequences. Repeatability was assessed by scanning five volunteers twice. MOAKS reproducibility was compared to MOAKS derived from a clinical knee MRI protocol by two readers. Statistical Tests Coefficients of variation (CVs), concordance confidence intervals (CCI), and Wilcoxon signed‐rank tests compared morphometry and relaxometry measurements with their reference standards. DESS MOAKS positive percent agreement (PPA), negative percentage agreement (NPA), and interreader agreement was calculated using the clinical protocol as a reference. Biomarker variations between Kellgren–Lawrence groups were evaluated using Wilcoxon rank‐sum tests. Results Cartilage thickness (P = 0.65), cartilage T2 (P = 0.69), and meniscus T2 (P = 0.06) did not significantly differ from their reference standard (with a 20° DESS flip angle). DESS slightly overestimated meniscus volume (P < 0.001). Accuracy and repeatability CVs were