CT灌注成像的时间-密度曲线及灌注参数在肺内肿块诊断中的作用

目的 探讨多层螺旋CT灌注成像的时间密度曲线及灌注参数在肺内良、恶性肿块鉴别诊断中的作用.方法 对64例肺内良、恶性肿块患者行16层螺旋CT灌注成像,应用CT体部灌注软件,分析肺内肿块的时间密度曲线(TDC)、灌注图像和各灌注参数值(PH、PHa /PHpm、BF、BV、PS、MTT).利用免疫组化染色测定微血管密度(MVD)并标定血管内皮生长因子(VEGF),评价肺内良、恶性肿块各灌注参数与MVD 及VEGF的相关性.结果 周围型肺癌和炎性肿块的TDC相似,二者与良性肿块的TDC明显不同.周围型肺癌与炎性肿块的PH、PHpm/PHa、BV差异无统计学意义(P>0.05);二者高于良性肿块者,差异有统计学意义(P<0.05).周围型肺癌的PS值大于炎性肿块和良性肿块,差异有统计学意义(P<0.05).VEGF阳性表达的周围型肺癌的PH、PHpm/PHa、BF、BV、PS值和MVD明显高于VEGF阴性表达者(P值均<0.05),也高于VEGF阳性表达的良性肿块者(P值均<0.05).VEGF阳性表达的周围型肺癌PH、PHpm/PHa、BF、BV、PS与MVD均呈正相关(P值均＜0.05).结论 多层螺旋CT灌注成像的时间密度曲线及灌注参数与肿瘤血管生成具有良好的相关性,能够反映肿瘤的微血管密度及VEGF表达,提供了一种定量评价肺内肿块血流模式的非创伤性方法 ,有利于肺内良、恶性肿块的鉴别诊断.

Diagnostic effect of time-density curve and parameters of CT perfusionimaging of peripheral pulmonary masses

Objective To investigate the effects of time-density curve (TDC) and perfusion parameters of multi-slice spiral CT perfusion imaging on the differential diagnosis of benign and malignant pulmonary masses. Methods Sixty-four patients with benign or malignant pulmonary masses underwent 16-slice spiral CT perfusion imaging. The CT body perfusion software was used for analysing TDC, perfusion parametric maps and the perfusion parameters (PH, PHpm /PHa, BF, BV,MTT). Immunohistochemical staining was performed to assess MVD and mark VEGF, and to evaluate the correlation of the perfusion parameters of benign and malignant pulmonary masses with MVD and VEGF. Results The TDC shape of peripheral lung cancers was similar to that of inflammatory masses, and TDC shape of lung cancers and inflammatory masses was significantly different from that of benign tumors. No significant difference was found in the PH, PHpm/PHa, BF, BV values between peripheral lung cancers and inflammatory masses (all P>0.05), and all were significantly higher than those of benign masses (all P<0.05). The PS value of peripheral lung cancers was higher than that of inflammatory masses and benign tumors (all P<0.05). The PH, PHpm /PHa, BF, BV, PS and MVD values of peripheral lung cancers with VEGF positive expression were significantly higher than those of the peripheral lung cancers with VEGF negative expression(all P<0.05), and than those of benign tumors with VEGF positive expression (all P<0.05).There was positive correlation between MVD and PH, PHpm/PHa, BF, BV, and PS of peripheral lung cancers with VEGF positive expression (all P<0.05). Conclusion TDC and perfusion parameters of multi-slice spiral CT perfusion imaging are closely correlated with tumor angiogenesis, reflecting MVD and VEGF expression, and thus providing not only a non-invasive method of quantitative assessment for blood flow patterns of peripheral pulmonary masses, but also an applicable diagnostic method for peripheral pulmonary masses.