^18F—FDGPET／CT诊断非小细胞肺癌纵隔淋巴结转移的方法和价值

目的本研究通过目测法、测量法以及模式识别方法对非小细胞肺癌（non—small cell lungcancer，NSCLC）患者纵隔淋巴结的PET／CT图像进行诊断分析，并与病理结果比较，探索各种诊断方法的诊断效能，为临床医生提供有关NSCLC区域淋巴结转移的准确信息。方法选择术前行全身PET／CT检查且经手术根治切除的NSCLC患者28例作为研究对象，由3名有经验的医生分别应用目测法及测量法对淋巴结的CT、PET以及PET／CT图像进行分析，并与病理结果进行对比；同时通过对淋巴结的PET和CT图像的提取，应用工程学一种新的模式识别方法进行分类诊断。结果CT、PET、PET／CT测量法对NSCLC淋巴结诊断的灵敏性分别为53．6％、80．4％、82．1％；特异度分别为92．2％、83．3％、90．6％；阳性预测值分别为68．2％、60．0％、73．0％；阴性预测值分别为86．5％、93．2％、94．2％；诊断符合率分别为83．1％、82．6％、88．6％；CT、PET、PET／CT目测法对NSCLC淋巴结诊断的灵敏性分别为53．6％、71．4％、69．6％；特异度分别为85．0％、82．2％、88．9％；阳性预测值分别为52．6％、55．6％、66．7％；阴性预测值分别为85．5％、90．2％、90．4％；诊断符合率分别为77．5％、79．7％、84．3％。模式识别法计算得出PET的灵敏度为88％，特异度为76％；CT的灵敏度为84％，特异度为66％。结论PET／CT测量法以及目测法对NSCLC淋巴结转移的诊断明显优于单独的CT或单独的PET；PET／CT测量法对NSCLC淋巴结转移的诊断明显优于目测法。初步探索了通过构建多分辨率直方图及支持向量机（SVM）分类判别的工程学方法对淋巴结图像进行分析，为今后多学科联合以及探索更准确的无创检查手段奠定了基础。

The method and efficacy of 18F-fluorodeoxyglucose PET/CT for diagnosing the metastasis of mediastinal lymph nodes in patients with non-small cell lung cancer

Objective The aim of this research is to diagnose and analyze the metastasis of mediastinal lymph nodes of non- small cell lung cancer（NSCLC） through the method of visual observation, measurement and the computer pattern recognition;then compared with the pathological diagnosis results, explored the diagnostic ef- ficiency of every method,Which can provide more accuracy information about N staging of NSCLC for the clinicians. Methods 28 cases of preoperative whole body PET/CT imaging with pathological - proven NSCLC were included in the study. Three practised doctors read the lymph nodes images of CT, PET and PET/CT through the method of visual observation and measurement, then compared with the pathological diagnosis. To analyze the lymph node images which were extracted through the new computer pattern recognition of engineering. Results Among CT,PET and PET/CT, the sensibility of mediastinal lymph node involvement was 53.6% , 80.4% and 82.1% respectively,the specificity was 92.2%, 83.3% and 90.6% respectively, the positive predictive value was 68.2% ,60% and 73.0% respectively, the negative predictive value was 86.5% ,93.2% and 94.2% respectively and the diagnosis coincidence rate was 83.1% ,82.6% and 88.6% respectively; For the method of visual observation, the sensibility of mediastinal lymph node involvement was 53.6% ,71.4% and 69.6% respectively,the specificity was 85.0% ,82.2% and 88.9% respectively, the positive predictive value was 52.6%, 55.6% and 66.7% respectively,the negative predictive value was 85.5% ,90.2% and 90.4% respectively and the diagnosis coincidence rate was 77.5% ,79.7% and 84.3% respectively. For the computer pattern recognition,the sensibility of PET and CT imaging were 88% and 84% separately, and the specificity was 76% and 66% separately. Conclusion The method of visual observation and measurement of PET/CT imaging for diagnosing the metastasis of mediastinal lymph nodes in patients with non - small cell lung cancer was advantage over the CT and PET imaging. And the method of measurement was advantage over the method of visual observation. This research preliminary explore the engineering method of SVM and multi - resolution histogram to analyze the image of lymph node, and settle a basis for the further combination of multiple subjects.