CT灌注成像对肺癌的诊断研究

目的 探讨CT灌注成像对肺癌的临床诊断价值。方法 选择临床鉴别诊断困难,可疑肺肿瘤的47例孤立性肺结节患者做CT灌注检查,按入选标准共有20例纳入研究。先行常规CT扫描,确定肺肿瘤中心部位,对选定肿瘤层面行灌注成像,包括组织的时间-密度曲线（Time-density curve,TDC）、血流量（Blood flow,BF）、血容量（Blood volume,BV）、对比剂平均通过时间（Mean transit time,MTT）、表面通透性（Permeability surface,PS）等参数,以此来评价并定量地反映孤立性肺结节的血流灌注状态。结果 孤立性肺结节的恶性与良性病变BV、MTT、BF、PS经分别进行两样本独立t检验,四组差异均有统计学意义（P〈0.01）;恶性病变BV、BF、PS明显高于良性病变,而MTT明显低于良性病变。比较传统CT常规扫描方法和CT灌注检查对孤立性肺结节的术前诊断准确率,分别为70%和95%,经χ2检验,其差异有统计学意义（P〈0.05）,显示CT灌注检查诊断符合率更高。结论 CT灌注能反映出孤立性肺结节的血流特点,其结合肺结节常规CT扫描的形态学特征能为肺癌的临床诊断提供重要依据,对临床治疗方案制定起到积极的指导作用。

Diagnositic value of CT perfusion imaging in lung cancer

Objective To assess the clinical value of CT perfusion imaging in diagnosing lung can-cer. Methods Forty-seven solitary pulmonary nodules patients with difficult differential diagnoses and suspicious lung tumor were chosen to receive CT perfusion examination. A total of 20 patients were selected according to the in-clusion criteria. Those patients received regular CT scan at first and the center of lung cancer was located. Then, CT perfusion scan at the chosen lay was carried out. The parameters of CT perfusion were calculated by GE CT perfusion software, including Time-density curve （TDC）, blood flow （BF）, blood volume （BV）, mean transit time （MTT） and permeability surface （PS）. The blood perfusion of solitary pulmonary nodules was evaluated and quantificationally re-flected by these parameters. Results BV, MTT, BF, PS in malignant and benign solitary pulmonary nodules were ana-lyzed by double-sample independent T test with statistically significant （P〈0.01）. BV, BF, PS of malignant solitary pul-monary nodules were significantly higher than that of benign solitary pulmonary nodules, while MTT was significant-ly lower than that of benign solitary pulmonary nodules. The accuracy rate of diagnosis of conventional CT scan and CT perfusion imaging were compared, which were 70% and 95% respectively. The value was evaluated by χ2 test, which showed that the accuracy rate of diagnosis of CT perfusion imaging was significantly higher than that of con-ventional CT scan. Conclusion CT perfusion can reflect the blood-flow characteristics of solitary pulmonary nod-ules. Combined with morphological characteristics of pulmonary nodules by regular CT scan, CT perfusion imaging can provide important bases for the diagnosis of lung cancer and guide clinical treatment.