Associations between apparent diffusion coefficient and electromyography parameters in myositis-A preliminary study

作者：Meyers Hans Jonas; Emmer Alexander; Kornhuber Malte; Surov Alexey

来源：Brain and Behavior, 2018, 8(5): e00958.

DOI：10.1002/brb3.958

<jats:title>Abstract</jats:title><jats:sec><jats:title>Objective</jats:title><jats:p><jats:styled-content style="fixed-case">MRI</jats:styled-content> is widely used in several muscle disorders. Diffusion‐weighted imaging (<jats:styled-content style="fixed-case">DWI</jats:styled-content>) is an emergent imaging modality sensitive to microstructural alterations in tissue. The apparent diffusion coefficient (<jats:styled-content style="fixed-case">ADC</jats:styled-content>) is used to quantify the random motion of water molecules. Electromyography (<jats:styled-content style="fixed-case">EMG</jats:styled-content>) is a clinically used diagnostic tool in myositis. The aim of this study was to elucidate possible associations between <jats:styled-content style="fixed-case">ADC</jats:styled-content> values and <jats:styled-content style="fixed-case">EMG</jats:styled-content> findings in myositis patients.</jats:p></jats:sec><jats:sec><jats:title>Method</jats:title><jats:p>Seven patients (eight investigated muscles) with myositis (mean age 51.43 ± 19 years) were included in this study. The diagnosis was confirmed by histopathology in every case. <jats:styled-content style="fixed-case">DWI</jats:styled-content> was obtained with a 1.5‐T scanner using two b‐values 0 and 1000 s/mm². In all patients, a needle electromyography (<jats:styled-content style="fixed-case">EMG</jats:styled-content>) was performed within 3 days to the <jats:styled-content style="fixed-case">MRI</jats:styled-content>. The following <jats:styled-content style="fixed-case">EMG</jats:styled-content> parameters were studied: motor unit action potential (<jats:styled-content style="fixed-case">MUAP</jats:styled-content>) amplitudes and durations, as well as pathological spontaneous activity. Spearman's correlation coefficient was used to analyze associations between investigated parameters.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>The estimated mean <jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>mean</jats:sub> value was 1.51 ± 0.29 × 10<jats:sup>−3 </jats:sup>mm²/s, mean <jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>min</jats:sub> was 1.28 ± 0.27 × 10<jats:sup>−3 </jats:sup>mm²/s, and mean <jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>max</jats:sub> was 1.73 ± 0.28 × 10<jats:sup>−3 </jats:sup>mm²/s. Correlation analysis identified significant associations between <jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>mean</jats:sub> and duration of the <jats:styled-content style="fixed-case">MUAP</jats:styled-content> (p<jats:italic> </jats:italic>= .78 P = .0279) and between <jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>min</jats:sub> and duration of the <jats:styled-content style="fixed-case">MUAP</jats:styled-content> (p = .85, P = .01). There were no significant differences according to pathological spontaneous activity.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p><jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>mean</jats:sub> and <jats:styled-content style="fixed-case">ADC</jats:styled-content><jats:sub>min</jats:sub> showed strong positive correlations with the duration of the <jats:styled-content style="fixed-case">MUAP</jats:styled-content> in myositis patients. Both modalities might similarly reflect muscle fiber loss in myositis patients.</jats:p></jats:sec>

• 出版日期2018-5