Kitano Masayuki, Kamata Ken, Imai Hajime, Miyata Takeshi, Yasukawa Satoru, Yanagisawa Akio, Kudo Masatoshi
Department of Gastroenterology and Hepatology, Kinki University Faculty of Medicine, Osaka, Japan.
Dig Endosc. 2015 Apr;27 Suppl 1:60-7. doi: 10.1111/den.12454.
The combination of second-generation ultrasound contrast agents and an endoscopic ultrasonography (EUS) system with a broad-band transducer has allowed contrast-enhanced harmonic imaging in the field of EUS. In contrast-enhanced harmonic EUS (CH-EUS), diffuse homogeneous enhancement is obtained in normal parenchyma of the pancreas. The bile duct and pancreatic duct are depicted as non-enhanced ductal structures with strong contrast in comparison to the surrounding parenchyma. CH-EUS identifies pancreatic adenocarcinomas as solid lesions exhibiting hypo-enhancement with a sensitivity and specificity of 88-96% and 88-94%, respectively. In particular, 80-100% of false-negative cases in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) are correctly classified by CH-EUS, suggesting CH-EUS complements EUS-FNA. Moreover, CH-EUS improves depiction of some subtle lesions in conventional EUS, thus facilitating EUS-FNA. For quantitative perfusion analysis, a time-intensity curve (TIC) for the region of interest can be generated during CH-EUS. The maximum intensity gain and the echo intensity reduction rate from the peak at 1 min obtained by TIC can be used for differentiation of pancreatic adenocarcinoma from other tumors. CH-EUS is also useful for differentiation of invasive intraductal papillary mucinous neoplasms (IPMN) from non-invasive IPMN, identification of malignant lesions in the gallbladder, and T- and N-staging of pancreatobiliary tumors.
第二代超声造影剂与配备宽带换能器的内镜超声（EUS）系统相结合，使得在EUS领域能够进行对比增强谐波成像。在对比增强谐波EUS（CH-EUS）中，胰腺正常实质可获得弥漫性均匀增强。与周围实质相比，胆管和胰管表现为无增强的导管结构，造影剂强烈。CH-EUS将胰腺腺癌识别为表现为低增强的实性病变，其敏感性和特异性分别为88%-96%和88%-94%。特别是，CH-EUS能正确分类80%-100%的内镜超声引导下细针穿刺活检（EUS-FNA）假阴性病例，表明CH-EUS可补充EUS-FNA。此外，CH-EUS能改善传统EUS中一些细微病变的显示，从而便于进行EUS-FNA。对于定量灌注分析，在CH-EUS过程中可生成感兴趣区域的时间-强度曲线（TIC）。TIC获得的1分钟时的最大强度增益和回声强度从峰值处的降低率可用于鉴别胰腺腺癌与其他肿瘤。CH-EUS对于鉴别浸润性导管内乳头状黏液性肿瘤（IPMN）与非浸润性IPMN、识别胆囊恶性病变以及胰胆管肿瘤的T分期和N分期也很有用。
