Nuñez-Peralta Claudia, Montesinos Paula, Alonso-Jiménez Alicia, Alonso-Pérez Jorge, Reyes-Leiva David, Sánchez-González Javier, Llauger-Roselló Jaume, Segovia Sonia, Belmonte Izaskun, Pedrosa Irene, Martínez-Noguera Antonio, Matellini-Mosca Briano, Walter Glenn, Díaz-Manera Jordi
Radiology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
Philips Healthcare Iberia, Madrid, Spain.
Front Neurol. 2021 Mar 16;12:634766. doi: 10.3389/fneur.2021.634766. eCollection 2021.
Magnetization transfer (MT) imaging exploits the interaction between bulk water protons and protons contained in macromolecules to induce signal changes through a special radiofrequency pulse. MT detects muscle damage in patients with neuromuscular conditions, such as limb-girdle muscular dystrophies or Charcot-Marie-Tooth disease, which are characterized by progressive fiber loss and replacement by fatty tissue. In Pompe disease, in which there is, in addition, an accumulation of glycogen inside the muscle fibers, MT has not been tested yet. Our aim is to estimate MT ratio (MTR) in the skeletal muscle of these patients and correlate it with intramuscular fat fraction (FF) and results of muscle function tests. We obtained two-point axial Dixon and Dixon-MT sequences of the right thigh on a 1.5 Teslas MRI scanner in 60 individuals, including 29 late onset Pompe disease patients, 2 patients with McArdle disease, and 29 age and sex matched healthy controls. FF and MTR were estimated. Muscle function using several muscle function tests, including quantification of muscle strength, timed test quality of life scales, conventional spirometry obtaining forced vital capacity while sitting and in the supine position, were assessed in all patients. MTR was significantly lower in Pompe patients compared with controls (45.5 ± 8.5 vs. 51.7 ± 2.3, Student -test, < 0.05). There was a negative correlation between the MTR and FF muscles studied (correlation coefficient: -0.65, Spearman test: < 0.05). MTR correlated with most of the muscle function test results. We analyzed if there was any difference in MTR values between Pompe patients and healthy controls in those muscles that did not have an increase in fat, a measure that could be related to the presence of glycogen in skeletal muscles, but we did not identify significant differences except in the adductor magnus muscle (48.4 ± 3.6 in Pompe vs. 51 ± 1.3 in healthy controls, Student -test = 0.023). MTR is a sensitive tool to identify muscle loss in patients with Pompe disease and shows a good correlation with muscle function tests. Therefore, the MT technique can be useful in monitoring muscle degeneration in Pompe disease in clinical trials or natural history studies.
磁化传递（MT）成像利用大量水质子与大分子中所含质子之间的相互作用，通过特殊射频脉冲诱导信号变化。MT可检测神经肌肉疾病患者的肌肉损伤，如肢带型肌营养不良症或夏科-马里-图斯病，其特征是进行性纤维丧失并被脂肪组织替代。在庞贝病中，除了肌肉纤维内糖原积累外，MT尚未进行过检测。我们的目的是评估这些患者骨骼肌中的MT比率（MTR），并将其与肌内脂肪分数（FF）以及肌肉功能测试结果相关联。我们在一台1.5特斯拉的MRI扫描仪上，对60名个体的右大腿进行了两点轴向狄克逊序列和狄克逊-MT序列扫描，其中包括29名晚发型庞贝病患者、2名麦克尔迪氏病患者以及29名年龄和性别匹配的健康对照者。估算了FF和MTR。对所有患者使用多种肌肉功能测试评估肌肉功能，包括肌肉力量量化、定时生活质量量表测试、常规肺活量测定（分别在坐位和仰卧位获取用力肺活量）。与对照组相比，庞贝病患者的MTR显著更低（45.5±8.5对51.7±2.3，Student检验，<0.05）。所研究肌肉的MTR与FF之间存在负相关（相关系数：-0.65，Spearman检验：<0.05）。MTR与大多数肌肉功能测试结果相关。我们分析了在脂肪未增加的那些肌肉中，庞贝病患者与健康对照者的MTR值是否存在差异，脂肪增加这一指标可能与骨骼肌中糖原的存在有关，但除了大收肌外，我们未发现显著差异（庞贝病患者为48.4±3.6，健康对照者为51±1.3，Student检验=0.023）。MTR是识别庞贝病患者肌肉损失的敏感工具，且与肌肉功能测试显示出良好的相关性。因此，MT技术在临床试验或自然史研究中可用于监测庞贝病患者的肌肉退化情况。
