MRI protocols for whole-organ assessment of the knee in osteoarthritis

Synarc Inc., San Francisco, CA 94105, USA.
Osteoarthritis and Cartilage (Impact Factor: 4.66). 02/2006; 14 Suppl A:A95-111. DOI: 10.1016/j.joca.2006.02.029
Source: PubMed

ABSTRACT One of the critical challenges in developing structure-modifying therapies for arthritis, especially osteoarthritis (OA), is measuring changes in progression of joint destruction. Magnetic resonance imaging (MRI) offers considerable promise in this regard. Not only can MRI quantify articular cartilage volume and morphology with high precision and accuracy, but it can also examine several other important articular components, and thus offer a unique opportunity to evaluate the knee and other joints as whole organs. On December 5 and 6, 2002, OMERACT (Outcome Measures in Rheumatology Clinical Trials) and OARSI (Osteoarthritis Research Society International), with support from various pharmaceutical companies listed at the beginning of this supplement, held a Workshop for Consensus on Osteoarthritis Imaging in Bethesda, MD. The aim of the Workshop was to provide a state-of-the-art review of imaging outcome measures for OA of the knee to help guide scientists and pharmaceutical companies who want to use MRI in multi-site studies of OA. Applications of MRI were initially reviewed by a multidisciplinary, international panel of expert scientists and physicians from academia, the pharmaceutical industry and regulatory agencies. The findings of the panel were then presented to a wider group of participants for open discussion. The following report summarizes the results of these discussions with respect to MRI acquisition techniques for whole-organ assessment of the knee in OA. The discussion reviews the selection and qualification of imaging sites for clinical trials, designing imaging protocols for whole-organ assessment of OA, and key considerations in image quality (IQ) control and data management.

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Available from: Bernard Dardzinski, Oct 08, 2014
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    • "The standard sequences in literature for these scanners have high in-plane resolution but usually have a larger interslice distance, and many assessment methods developed for such sequences are on a slice-by-slice basis. For a thorough review of MRI scan protocols for knee OA assessment, see [5]. A recent study shows that low-field dedicated extremity MRI can provide similar information on bone erosions and synovitis as expensive high-field MRI units [6]. "
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    ABSTRACT: We present a fully automatic method for articular cartilage segmentation from magnetic resonance imaging (MRI) which we use as the foundation of a quantitative cartilage assessment. We evaluate our method by comparisons to manual segmentations by a radiologist and by examining the interscan reproducibility of the volume and area estimates. Training and evaluation of the method is performed on a data set consisting of 139 scans of knees with a status ranging from healthy to severely osteoarthritic. This is, to our knowledge, the only fully automatic cartilage segmentation method that has good agreement with manual segmentations, an interscan reproducibility as good as that of a human expert, and enables the separation between healthy and osteoarthritic populations. While high-field scanners offer high-quality imaging from which the articular cartilage have been evaluated extensively using manual and automated image analysis techniques, low-field scanners on the other hand produce lower quality images but to a fraction of the cost of their high-field counterpart. For low-field MRI, there is no well-established accuracy validation for quantitative cartilage estimates, but we show that differences between healthy and osteoarthritic populations are statistically significant using our cartilage volume and surface area estimates, which suggests that low-field MRI analysis can become a useful, affordable tool in clinical studies
    IEEE Transactions on Medical Imaging 02/2007; 26(1-26):106 - 115. DOI:10.1109/TMI.2006.886808 · 3.80 Impact Factor
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