MAVRIC-SL (MVSL), a multi-spectral magnetic resonance imaging (MRI) sequence [1] used for visualization of tissues near hip arthroplasty, can be accelerated by a short calibration scan [2], permitting an isotropic acquisition in a clinically feasible scan time. Decreasing the repetition time (TR) can further reduce scan time. This study evaluated the feasibility of acquiring isotropic MAVRIC-SL images (MVISO) and reduced TR isotropic MAVRIC-SL images (TRMVISO) of hip arthroplasties to elucidate the added clinical benefit of such acquisitions. Following IRB approval, MVSL, MVISO and TRMVISO images were acquired for 93 hip arthroplasties (84 subjects). Images were reviewed by 2 radiologists to evaluate clinical and image quality features. Comparison of features between scanning sequences was assessed by mixed-effects ordinal logistic regression and odds ratios (OR). Inter/intra-rater agreement was determined using Gwet's agreement coefficient (AC).Introduction
Methods
Failure of metal on metal (MOM) total hip arthroplasty (THA) and resurfacing arthroplasty (HRA) due to development of adverse local tissue reaction (ALTRs) is a significant problem. The prevalence of ALTRs in asymptomatic MOM arthroplasty patients is highly variable. The purpose of this prospective, longitudinal study was to: 1) determine MRI ALTR prevalence in patients with HRA; 2) determine if patients with HRA have a greater rate of MRI ALTRs compared to control patients with ceramic on poly (COP) THA; and 3) evaluate changes in patient reported outcomes between these implant designs. Following IRB approval with informed consent, self-reported asymptomatic primary COP and HRA patients greater than one year post arthroplasty were evaluated with 4 annual (TP1–4) MRIs using a standardized protocol and serum ion level testing. Morphologic and susceptibility reduced images were acquired for each hip and evaluated for synovial thickness, volume, capsule dehiscence and the presence of ALTR. Patient reported outcomes were evaluated by Hip Disability and Osteoarthritis Outcome Scores (HOOS). Analyses were performed to detect differences of synovial thickness and volume, and HOOS subgroups between and within bearing surfaces at each time point and over time, and to compare the time to and the risk of developing MRI ALTR. Analyses were adjusted for age, gender, and length of implantation.Introduction
Methods
