Improving Accuracy and Reproducibility of Cartilage T2 Mapping in the OAI Dataset Through Extended Phase Graph Modeling

作者：Marco Barbieri, Anthony A. Gatti, Feliks Kogan · 发表于：Journal of Magnetic Resonance Imaging · 年份：2024 · DOI：10.1002/jmri.29646 · 被引用次数：4 · 研究领域：Osteoarthritis Treatment and Mechanisms、Rheumatoid Arthritis Research and Therapies、Total Knee Arthroplasty Outcomes

Background The Osteoarthritis Initiative (OAI) collected extensive imaging data, including Multi‐Echo Spin‐Echo (MESE) sequences for measuring knee cartilage T 2 relaxation times. Mono‐exponential models are used in the OAI for T 2 fitting, which neglects stimulated echoes and B 1 inhomogeneities. Extended Phase Graph (EPG) modeling addresses these limitations but has not been applied to the OAI dataset. Purpose To assess how different fitting methods, including EPG‐based and exponential‐based approaches, affect the accuracy and reproducibility of cartilage T 2 in the OAI dataset. Study Type Retrospective. Population From OAI dataset, 50 subjects, stratified by osteoarthritis (OA) severity using Kellgren–Lawrence grades (KLG), and 50 subjects without OA diagnosis during OAI duration were selected (each group: 25 females, mean ages ~61 years). Field Strength/Sequence 3‐T, two‐dimensional (2D) MESE sequence. Assessment Femoral and tibial cartilages were segmented from DESS images, subdivided into seven sub‐regions, and co‐registered to MESE. T 2 maps were obtained using three EPG‐based methods (nonlinear least squares, dictionary matching, and deep learning) and three mono‐exponential approaches (linear least squares, nonlinear least squares, and noise‐corrected exponential). Average T 2 values within sub‐regions were obtained. Pair‐wise agreement among fitting methods was evaluated using the stratified subjects, while reproducibility using healthy subjects. Each method's T 2 a...