孤立性肺结节双源CT灌注成像与微血管构成的相关性研究

Solitary pulmonary nodules(SPN) is a common radiological signs, which is key to early diagnosis and treament of lung cancer. CT perfusion imaging(CTPI) has the significant value in the quantitative and qualitative research of tumor. Previous studies showed that there are significant differences between CT perfusion parameters of benign SPNs and malignant SPNs. However, CTPI findings of malignant SPNs and inflammatory SPNs are often overlapping, differential diagnosis is difficult. There is a relationship between CT perfusion parameters and microvessel density(MVD) in SPNs, but no statistical differences between benign SPNs and malignant SPNs in MVD. In recent years, the immunohistochemical study of tumor angiogenesis found that the maturity of microvessel was different among benign SPNs, malignant SPNs and inflammatory SPNs. According to a large number of recent documents and our studies,flash dual source computed tomography has obvious advantages in radiation protection technology, scanning speed, perfusion parameter types, perfusion image quality,etc. It is conducive to the study of CTPI in SPN.In the present project, We plan to introduce luminal vascular parameters to do a quantitative analysis of the microvascular structure in SPN, and perform a comparative analysis with flash dual source CT perfusion parameters of SPN, and provide a more objective theoretical basis for exploring CTPI characteristics of SPNs.This is helpful for the diagnosis and differential diagnosis of SPNs.

孤立性肺结节（SPN）是一种常见的放射学征象。SPN的诊断和鉴别诊断是肺癌早诊早治的关键。CT灌注成像（CTPI）在肿瘤的定量、定性研究中有重要价值。既往研究显示，良性、恶性SPN的CT灌注参数之间具有显著性差异，但是恶性、炎性SPN的CTPI表现常存在重叠，鉴别诊断困难；SPN的多项CT灌注参数与MVD具相关性，但是良性、恶性SPN的MVD之间无统计学差异。近年来，通过免疫组化对肿瘤血管生成的研究发现，良性、炎性及恶性SPN的微血管腔成熟度不同。根据大量文献和申请人的工作积累，炫速双源CT在辐射防护、扫描速度、灌注参数种类及灌注图像质量等具有明显优势，有利于开展SPN的CT灌注成像研究。本项目拟引入有腔血管参数来定量分析SPN的微血管构成，并与SPN的炫速双源CT灌注参数对比分析，为探究不同性质SPN的CTPI特点提供较为客观的理论依据，有助于SPN的诊断与鉴别诊断。

孤立性肺结节（SPN）的诊断和鉴别诊断是肺癌早诊早治的关键。不同性质SPN的微血管构成不同，CT灌注成像可在微血管水平反映肿瘤的血供状态，在肿瘤的定量、定性研究中有重要价值。双源CT在辐射防护技术、扫描速度及灌注图像质量等具有明显优势，有利于开展SPN的CT灌注成像研究。（1）应用双源CT灌注成像研究65例孤立性肺结节的CT灌注参数与MVD、有腔血管参数（LVN、LVA、LVP）及有腔血管比（LVN/MVD）的相关性，评价双源CT灌注成像对SPN的鉴别诊断价值。结果显示，良性组BV、BF、MVD、有腔血管参数明显低于恶性及炎性组，恶性组PMB高于炎性组。CT灌注参数BF、BV、PMB与微血管参数MVD、LVN、LVA、LVP及LVN/MVD均有相关性，BF与LVN相关性最好，BV与LVA相关性最好，PMB与LVN/MVD相关性最好。根据受试者操作特性（ROC）曲线分析，联合BF、BV与PMB，其ROC曲线下面积（AUC)为0.760，当BF≥44ml/100ml/min，BV≥6.00ml/100ml，PMB≥9.26ml/100ml/min时，SPN被诊断为恶性结节的敏感性为82%，特异性为61%。研究表明，良性、炎性、恶性组SPN的微血管数量和成熟度不同。双源CT灌注参数与有腔血管参数（尤其是有腔血管比）的相关性好于MVD。CT灌注参数可作为无创评价肿瘤血管生成的指标，有助于SPN的鉴别诊断。（2）应用双源CT灌注成像研究38例肺癌的CT灌注参数BF、BV、MTT、PS与肺癌大小的关系。研究表明，肺癌大小与CT灌注参数PS有相关性，肿瘤越大PS均值越小，与BF、BV、MTT无相关性。双源CT 灌注成像可为不同大小肺癌的生物学行为评价提供理论基础。（3）应用双源CT灌注成像研究42例非小细胞肺癌（NSCLC）CT灌注参数与区域淋巴结转移的相关性，探讨双源CT灌注成像诊断NSCLC区域淋巴结转移的价值。结果显示，NSCLC有淋巴结转移组的BF及LVA均高于无淋巴结转移组，MTT及PMB低于无淋巴结转移组。BF及LVA与NSCLC发生区域淋巴结转移具相关性。BF对诊断NSCLC区域淋巴结转移具有较高的价值，可作为术前预测NSCLC区域淋巴结转移的参考指标。