“Vessel” is a generic term for arteries, veins, and lymphatic vessels, and arteries and veins are called “blood vessels.” Vascular disease is comprised of arterial disease (diseases of cerebral/carotid arteries, aorta, and arteries in the abdomen/kidney/periphery, etc.) and venous disease (e.g., deep venous thrombosis). With an increase in arteriosclerotic disease in recent years, methods for diagnosing arterial disease that are noninvasive and minimally invasive have been attracting more and more attention. Because arteries are located throughout the body, attention must be paid to all organs in the body as well as to the characteristics and specificity of arteries when diagnosing arterial disease. This report is aimed at providing a standard method for ultrasound assessment of “aortic and peripheral arterial lesions,” which are forms of arteriosclerosis that are on the rise in association with aging and lifestyle-related diseases (e.g., diabetes mellitus, dyslipidemia, hypertension, smoking, obesity). We have to know the details of vascular diseases and examine them by vascular ultrasound according to the standard method.

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As ultrasound (US) is a simple and less invasive modality, it is widely used for mass screening. Both gallbladder polyps and thickened wall are common findings. As the diagnostic accuracy of US depends on the skill and knowledge of the sonographer, sonographers should master the standard scanning method and learn characteristic findings for the differential diagnosis. First, we explain the important findings for the differential diagnosis of gallbladder tumors and thickened wall, citing the categorized criteria for US cancer screening of the Japanese Society of Gastroenterological Cancer Screening. Second, we highlight indirect US findings such as gallbladder distension and debris as useful findings for detecting small gallbladder carcinomas and occult lesions of the pancreatobiliary tract.

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Purpose: A method for determining the acoustic parameters of thin biological tissues using an acoustic microscope is proposed, taking into account multiple reflection. Subjects and Methods: In the method, the acoustic parameters of velocity, attenuation, and acoustic impedance are determined using measured phase and amplitude at around 10 different frequencies. Conclusion: The results of numerical calculations for simulation data including ±5% random errors show that the determination precision of the velocity, attenuation, and acoustic impedance are ±0.04%, ±2.7%, and ±1.2%, respectively.

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Purpose: The change in maximum tumor diameter is generally used to evaluate clinical response to neoadjuvant chemotherapy (NAC) for breast cancer. However, there are cases in which accurate evaluation cannot be performed due to internal necrosis or scar tissue. The objectives of this study were to examine whether accurate evaluation can be performed by addition of contrast-enhanced ultrasound (CEUS) using Sonazoid^® and to examine on what types of CEUS findings one should focus. Subjects and Methods: The subjects were 20 breast cancer patients (22 nodules) who had undergone CEUS before and after NAC followed by surgery in our hospital between July 2007 and July 2010. Sonazoid^® suspension (0.0075 ml/kg) was injected intravenously. The nodules were classified into the following five categories based on micro flow images and video taken for 1 min after injection: the tumor interior was not contrast enhanced, had the same enhancement as the non-tumor area, was slightly more enhanced than the non-tumor area, was more strongly enhanced than the non-tumor area, and was non-evaluable. Three categories were used to classify peritumoral contrast enhancement and intratumoral non-contrast enhanced areas: absent, present, and non-evaluable. The results based on these categories were compared with histological responses to NAC. Results and Discussion: Peritumoral and intratumoral contrast enhancement tended to decrease after NAC compared with before NAC. This tendency was stronger in nodules that showed a good histological response. There was no consistent trend between histological responses and intratumoral non-enhanced areas. It suggests the need to evaluate not only absence or presence of non-enhanced areas but also changes in tumor size and the state of enhanced areas. Conclusion: The effectiveness of NAC can be evaluated by the assessment of intratumoral and peritumoral contrast enhancement using CEUS.

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Purpose: We investigated whether ultrasound elastography was useful for evaluating uterine muscle contractions in women with threatened premature and terminal labor. Subjects and Methods: A total of 17 pregnant women (two women with threatened premature labor and 15 women with terminal labor) were recruited to the study. Elastographic images of abdominal fat and the uterine muscular layer were recorded during uterine contractions and relaxations, and color changes in the muscle were observed. We measured the elasticity of uterine muscle (A) and fatty tissue (B), and calculated B/A ratios. The ratio during contractions was compared with that during relaxations by Wilcoxon's test. Results and Discussion: The muscle color changed with its contraction in all women. The B/A ratios during contractions and relaxation were as follows, respectively: 28.2 and 1.3 for threatened premature labor, 31.2 and 2.5 for the latent phase of the first stage of labor, 49.9 and 2.64 for the active phase of the first stage of labor, and 47.9 and 6.13 for the second stage of labor. There were differences between the two in all stages. Conclusions: Ultrasound elastography made it possible to evaluate whether uterine muscle contracts or not in women with premature preterm and term labor.

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Collecting duct carcinoma, also known as Bellini duct carcinoma, is a renal tumor with poor prognosis that accounts for only 1% of all renal cancers. We encountered a rare case of collecting duct carcinoma infiltrating into the entire right kidney. The patient was a man in his 60s. Abdominal ultrasonography demonstrated an enlarged right kidney, which appeared to be occupied by a tumor with poorly defined margins. The central echo complex of the kidney appeared extremely narrow due to tumor growth. However, the reniform shape was relatively well-preserved despite the large size of the tumor. Tumor echogenicity was almost isoechoic when compared with the cortex of the normal left kidney. Doppler imaging demonstrated that the tumor was scarcely fed by the tumor vessels. To the best of our knowledge, no previous reports have precisely described sonographic features of collecting duct carcinoma. Although 63 reports have been published in Japan since 1988, most have described only the findings from computed tomography and/or pathological examination. According to this literature, preservation of a reniform shape was found in 72% (21/29) of cases, and tumor hypovascularity was evident in 96% (52/54). On the other hand, diffuse infiltrating growth into the entire kidney, as in the present case, was seen in only 11% (7/62). Considering these past reports and the findings in the present case, sonography of collecting duct carcinoma could show the following features: 1) infiltrative growth; 2) preservation of reniform shape irrespective of tumor size; 3) deformity or narrowing of the central echo complex due to tumor growth; 4) hypovascularity on Doppler imaging; and 5) non-characteristic echogenicity depending on individual cases. When such imaging findings are apparent on sonography, collecting duct carcinoma should be included among the differential diagnoses.

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