高分辨MRI对胸膜病变诊断价值的初步探讨

目的　探讨高分辨磁共振成像 (highresolutionmagneticresonanceimaging ,HR MRI)对胸膜病变的诊断价值。方法　对 5例正常志愿者和 4 4例胸膜病变患者行常规MRI和HR MRI检查 ,对其中 2 0例进行了图像对比噪声比 (CNR)与信号强度比 (SIR)的测量 ,比较分析常规MRI和HR MRI对胸膜病变的诊断价值。结果　HR MRIT1WI对 5例正常人胸壁主要结构的显示情况明显优于常规MRT1WI (P <0 .0 0 5 )。在HR MRI与常规MRI比较中 ,2 0例胸膜病变的CNR及SIR的绝对值前者均高于后者 (P <0 .0 5 )。HR MRI对胸壁或膈肌浸润的发现率较常规MRI要高 ,而对弥漫性胸膜增厚、纵隔胸膜受累和不规则环绕形胸膜增厚的发现率与常规MRI相当甚至更差 ,但上述差异均无显著性意义(P >0 .0 5 )。常规MRI与HR MRI 常规MRI对良、恶性胸膜病变的鉴别诊断的敏感性分别为 72 %、88% ,特异性为 5 3%、75 % ,正确率为 6 8%、84 % ,阳性预测值为 82 %、90 % ,阴性预测值为 4 4 %、6 9%。但常规MRI与HR MRI相结合对良恶性胸膜病变的鉴别诊断价值与单纯的常规MRI比较无明显差异(P >0 .0 5 )。结论　HR MRI提高了图像空间分辨率 ,增加了胸膜病变与肋间肌信号的对比 ,并且可以清楚地显示最内肋间肌及其内侧的胸膜外脂肪线等邻近胸膜的胸壁深层结构 ,有利

Value of high resolution MRI in the diagnosis of pleural disease

Objective To explore the value of high resolution magnetic resonance imaging (HR MRI) in the diagnosis of pleural disease. Methods Five normal volunteers and 44 patients with pleural disease were examined with HR MRI and routine MRI. The values of contrast to noise ratio (CNR) and signal intensity ratio (SIR) of the images from 20 patients were measured.Results The chest wall structures of 5 normal volunteers were displayed more clearly by HR MRI T 1WI than routine MRI T 1WI ( P <0.005). The absolute values of CNR and SIR of HR MRI images of pleural lesions were higher than those of routine MRI ( P <0.05). Chest wall and/or diaphragmatic invasion could be better detected by HR MRI than by routine MRI. However, HR MRI was not so sensitive as routine MRI in demonstrating the mediastinal pleural involvement. Using routine MRI alone and routine MRI in combination with HR MRI, the sensitivities, specificities, corrective rates, positive predictive values, and negative predictive values in distinguishing malignant from benign pleural disease were 72% and 88%, 53% and 75%, 68% and 84%, 82% and 90%, and 44% and 69%, respectively. But in general, no significant superiority was found in routine MRI in combination with HR MRI than that of routine MRI alone ( P >0.05). Conclusion HR MRI improves not only spatial resolution of the tissues, but also increases the contrast of signal intensity between intercostal muscles and pleural lesions. HR MRI can reveal delicate deeper layer structure of chest wall which is closely next to parietal pleural such as extrapleural fat layer, innermost intercostal muscles and so on, so it has advantage in early detecting the pleural lesion infiltration on chest wall. HR MRI can be applied to the diagnosis of pleural disease as a supplementary method for the routine MRI.