Dietrich C F, Ignee A, Hocke M, Schreiber-Dietrich D, Greis C
Med. Klinik 2, Caritas-Krankenhaus Bad Mergentheim, Bad Mergentheim, Germany.
Z Gastroenterol. 2011 Mar;49(3):350-6. doi: 10.1055/s-0029-1245851. Epub 2011 Mar 9.
Ultrasound is the method of choice in the detection and characterization of diffuse and focal organic diseases. For B-mode and colour (power) Doppler ultrasound, besides manual skills, (hands-on) a technical knowledge about ultrasound images is of the upmost importance for the investigator. Contrast enhanced ultrasound (CEUS) has become an important diagnostic tool for hepatic, renal, pancreatic indications and several others due to: (a) an increasing rate of studies resulting in sufficient evidence especially in hepatic indications, (b) a rate of adverse events close to zero (1:10,000 in comparison to iodinated contrast agents from 1-12:100) enabling the application of CEUS in patients with severe renal insufficiency or thyroid gland autonomy, and (c) a reasonable price (depends on the country and influence of the health-care system [reimbursement]) and the dosage used. Mini-doses from 0.1 to 0.4 mL are used depending on the contrast agent and applied indication. Therefore a well founded knowledge concerning the technical aspects of CEUS is important for the investigator to avoid misinterpretation especially when artefacts specific for CEUS occur. Special literature is rare. In the presented article we present pitfalls concerning CEUS. The following aspects are considered and illustrated by images: (i) acoustic power (mechanical index) and other aspects resulting in micro bubble destruction, (ii) the possibility of false positive contrast signals in non-vascularized areas, (iii) attenuation caused by too high contrast agent dose, (iv) influence of the frame rate on the spatial resolution, (v) dealing with deep located lesions, (vi) differences in focus positioning in detection and characterization studies, (vii) advantages and disadvantages of replenishment studies, (viii) reliability of contrast enhanced spectral Doppler measurements.
超声是检测和鉴别弥漫性及局灶性器质性疾病的首选方法。对于B型和彩色（能量）多普勒超声，除了手动操作技能外，研究人员对超声图像的技术知识至关重要。对比增强超声（CEUS）已成为肝脏、肾脏、胰腺及其他多种疾病的重要诊断工具，原因如下：（a）研究数量不断增加，尤其在肝脏疾病方面有足够证据；（b）不良事件发生率接近零（与碘造影剂的1:100至12:100相比为1:10,000），使得CEUS可应用于严重肾功能不全或甲状腺自主性疾病患者；（c）价格合理（取决于国家和医疗保健系统的影响[报销情况]）以及所用剂量。根据造影剂和应用指征，使用0.1至0.4 mL的小剂量。因此，研究人员掌握扎实的CEUS技术知识对于避免误解非常重要，尤其是在出现CEUS特有的伪像时。专门的文献很少。在本文中，我们介绍了CEUS的陷阱。通过图像对以下方面进行了考虑和说明：（i）声功率（机械指数）及导致微泡破坏的其他方面；（ii）非血管化区域出现假阳性对比信号的可能性；（iii）造影剂剂量过高引起的衰减；（iv）帧率对空间分辨率的影响；（v）处理深部病变；（vi）检测和鉴别研究中焦点定位的差异；（vii）补充研究的优缺点；（viii）对比增强频谱多普勒测量的可靠性。
