Elevated adiabatic T 1ρ and T 2ρ in articular cartilage are associated with cartilage and bone lesions in early osteoarthritis: A preliminary study

To evaluate adiabatic T and T of articular cartilage in symptomatic osteoarthritis (OA) patients and asymptomatic volunteers, and to determine their association with magnetic resonance imaging (MRI)-based structural abnormalities in cartilage and bone. A total of 24 subjects (age range: 50-68 years; 12 female) were enrolled, including 12 early OA patients and 12 volunteers with normal joint function. Patients and volunteers underwent 3T MRI. T , adiabatic T , and T relaxation times of knee articular cartilage were measured. Proton density (PD)- and T -weighted MR image series were also obtained and separately evaluated for morphological changes using the MRI OA Knee Scoring (MOAKS) system. Comparisons using the Mann-Whitney nonparametric test were performed after dividing the study participants according to physical symptoms as determined by Western Ontario and McMaster Universities (WOMAC) score or presence of cartilage lesions, bone marrow lesions, or osteophytes. Elevated adiabatic T and T relaxation times of articular cartilage were associated with cartilage loss (P = 0.024-0.047), physical symptoms (0.0068-0.035), and osteophytes (0.0039-0.027). Elevated adiabatic T was also associated with bone marrow lesions (0.033). Preliminary data suggest that elevated adiabatic T and T of cartilage are associated with morphological abnormalities of cartilage and bone, and thus may be applicable for in vivo OA research and diagnostics. 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:678-689.