Development of Endoscopic Ultrasound System for Tissue Elasticity Imaging

超声组织弹性成像可以为我们提供基于组织硬度的新的诊断信息，因此有望以高对比度检测肿瘤并鉴别良恶性疾病。我们最近开发了基于组合自相关方法的商用实时组织弹性成像设备，该方法旨在通过简单的操作获得与普通超声检查一样高的诊断精度。另一方面，传统的弹性图像由于依赖于压缩程度而不是定量的。从这一角度出发，我们的目标是通过量化常规应变图像和扩展临床…的视野来开发用于组织弹性成像的内窥镜超声系统更多的应用。(1)主动压迫型组织弹性成像通过对组织的压缩，在组织内产生应变以及触诊。为此，对经直肠探头前列腺检查系统进行了研究。用水充气的气球是为了均匀的应力分布和不依赖操作者的技能而研制的。2)被动压缩型组织弹性成像在这种类型中，组织的变形是由心脏运动或血压引起的。研制了经食管型探头评价主动脉斑块的系统。3)组织弹性的定量测量为了阐明组织弹性与病理意义之间的关系，采用机械压缩试验机对体模和组织标本进行了测量，为发展超声内窥镜组织弹性成像系统提供了基础技术，为实际系统的开发提供了指导

Ultrasonic tissue elasticity imaging can provide us novel diagnostic information based on tissue hardness and consequently it is expected to detect tumor with high contrast and also discriminate benign and malignant disease. We recently developed commercial-based equipment for real-time tissue elasticity imaging based on the combined autocorrelation method which we have previously proposed to attain the high precision of diagnosis with simple operation as well as ordinary ultrasonic examination. On the other hand, there remains a problem that conventional elasticity image is not quantitative since it depends on the compression level. In addition, endoscopic measurement is expected to be useful for improving precision of diagnosis based on tissue characterization as well as percutaneous approaches.From this point of view, we aim to develop the endoscopic ultrasound systems for tissue elasticity imaging by quantification of conventional strain images and expansion of fields for clinical … More application.(1) Active compression type of tissue elasticity imagingBy compression of tissues, strain is induced within tissue as well as palpation. As this type, the system for prostate examination by using transrectal probe was investigated. The balloon which was inflated by water was developed for uniform distribution of stress and independence of operators' skill2) Passive compression type of tissue elasticity imagingDeformation of tissues is induced by cardiac motion or blood pressure in this type. The system for evaluation of aortic plaque by transesophageal type of probe was developed. Ultrasonic endoscope was used for reconstruct strain images of pancreas disease.3) Quantitative measurement of tissue elasticityTo elucidate the relation of tissue elasticity and pathological meaning, phantom and tissue specimen are measured by mechanical compression-tester.By way of these investigations, it was attained to develop the basic technology for the endoscopic ultrasound systems for tissue elasticity imaging and give direction to development of practical system Less