Background: Mediastinal involvement in lung cancer is an important prognostic factor affecting survival, and accurate staging of the mediastinum lymph node correctly identifies patients who can benefit the most from surgery. The aim of this study is to investigate the value of dual-energy spectral computed tomography (DEsCT) imaging in differentiating metastatic from non-metastatic lymph nodes in lung cancer.
Methods: Forty-eight patients with non-small cell lung cancer (NSCLC) underwent arterial (AP) and portal venous (PP) phase contrast-enhanced DEsCT imaging followed by surgical treatment. gemstone spectral imaging (GSI) data images were reconstructed and transmitted to an offline workstation. GSI quantitative parameters, including lymph-node size, CT value, IC, water concentration, and spectral curve. Differences were tested for statistical significance using the two-sample t test. ROC analysis was performed to assess diagnostic performance.
Results: The mean short-axis diameter of metastatic LNs, slope of the spectral Hounsfield unit curve (λHU), normalized iodine concentration measured during, and both AP and PP were significantly higher in metastatic lymph node than that in benign lymph nodes. The best parameter for detecting metastatic lymph nodes was AP λHU when a threshold λHU of 2.75 was used; sensitivity, specificity, and accuracy were 88.2%, 88.4%, and 87.0%, respectively.
Conclusions: Quantitative assessment with gemstone spectral imaging quantitative parameters showed higher accuracy than the qualitative assessment of conventional CT imaging features for the preoperative diagnosis of metastatic lymph nodes in patients with lung cancer. .
背景与目的 肺癌淋巴结转移是重要的生存预后因素，准确的纵隔淋巴结分期可以使患者最大程度地受益于手术。本研究旨在探讨宝石能谱计算机断层扫描（computed tomography, CT）定量参数在术前诊断非小细胞肺癌（non-small cell lung cancer, NSCLC）患者淋巴结转移的价值。方法 收集48例NSCLC患者，连续进行宝石能谱CT成像（gemstone spectral imaging, GSI）模式肺增强扫描和手术治疗。重建GSI数据，测量淋巴结的大小、动脉期和静脉期的CT值、能谱曲线的斜率、标准化碘浓度以及水浓度。采用独立样本的t检验，并进行受试者工作特征曲线（receiver operating characteristic, ROC）分析，确定诊断的最佳阈值及效能。结果 转移性淋巴结与非转移性淋巴结短轴直径、动脉期和静脉期的CT值、能谱曲线的斜率、标准化碘浓度均有统计学差异。当确定动脉期能谱曲线斜率的最佳临界值为2.75，其诊断的敏感性、特异性及总体的准确性分别为88.2%、88.4%、87.0%。结论 能谱CT的GSI模式定量参数较传统CT在术前诊断转移性淋巴结方面有更高的诊断效能。.