MR spectroscopy is able to quantify intramyocellular lipids, intrahepatic lipids, and marrow adipose tissue in several clinical conditions.
Learning objectives: ·
To review MR spectroscopy techniques to assess muscle, liver, and marrow ·
To review clinical conditions associated with abnormal lipid distribution.
Obesity is associated with increased intramyocellular lipids (IMCL) and intrahepatic lipids (IHL) which play important roles in the pathogenesis of insulin resistance. Both fat compartments can be quantified using proton MR spectroscopy. Imaging protocols for quantification of IMCL and IHL and clinical applications will be reviewed.
Recent studies have revealed an important link between bone and fat. Both bone and fat cells arise from a common mesenchymal stem cell within bone marrow, capable of differentiation into osteoblasts and adipocytes. Elevation in marrow adipose tissue (MAT) has been shown to be an indicator of bone weakening. MAT content and composition can be quantified by proton MR spectroscopy. Clinical conditions associated with abnormal MAT content and composition and imaging protocols for MAT assessment will be reviewed.
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