Unlike X-rays, ultrasound diagnosis is a highly noninvasive and safe diagnostic method that can be used for fetal diagnosis without exposure to radiation. In addition, it is simple enough to acquire cross-sectional images of the body simply by applying an ultrasound probe to the body surface, and it has portability that allows the device to be miniaturized. Therefore, ultrasound examinations are also available at the bedside or in the surgical field. Furthermore, it is excellent for real-time observation of moving tissues such as the heart and blood and serves as an indispensable diagnostic method in clinical practice. B mode (brightness mode) is the most basic image diagnosis mode in ultrasonic diagnosis. To correctly interpret B-mode images that reflect the complicated wave propagation in living tissues, it is important to understand the principle of image reconstruction based on the pulse-echo method, image resolution, and the mechanism of artifact generation. This paper highlights these and outlines them with some experimental results. Also, examples of new developments in B-mode imaging are presented.

Contrast-enhanced ultrasound (CEUS) is a powerful tool to detect viable tumor lesions effectively because of the higher diagnostic sensitivity of images; however, it is difficult to evaluate microvascular perfusion quantitatively. Alternatively, time intensity curve (TIC) parameters measured using CEUS have been compared as quantitative analysis for blood perfusion. There are two major analysis methods using TIC: wash-in and wash-out curve and flash replenishment curve. Unfortunately, there is a big fluctuation of intensity in decibel according to the depth and/or size of the region of interest on CEUS, and it is also inevitable that curve fitting analysis runs the risk of error on TIC parameters according to the CEUS examination time. Basically, it is difficult for physicians to identify the degree of change in blood flow based on analysis of TIC parameters. Meanwhile, the epoch-making new technology, Contrast Vector Imaging^®, has been launched. It can directly measure microvascular perfusion by quantitative imaging analysis of Sonazoid bubble tracking. Recently, anti-tumor therapeutic strategies have been developed. We need to establish a standard technique for quantitative assessment of microvascular perfusion on CEUS, which is expected to contribute significantly to early tumor response assessment of anti-tumor therapies in the future.

Although Cushing’s syndrome causes left ventricular hypertrophy and increases cardiovascular risk, its mechanism remains mostly unclear. We report a case of a patient with Cushing’s syndrome caused by an adrenal adenoma, whose preoperative and postoperative cardiac morphology and function were observed over time using transthoracic echocardiography. The patient was a 30-year-old woman referred to us for refractory hypertension. Echocardiography revealed a left ventricular wall thickness of 14 mm and a relative wall thickness of 0.76, indicating significant concentric hypertrophy. We suspected secondary hypertension and performed various hormone tests. Blood adrenocorticotropic hormone (ACTH) was suppressed and blood cortisol was within the normal range. Detailed examinations revealed high nighttime cortisol levels, no response to ACTH in the adrenocorticotropic hormone-releasing hormone challenge test, and no inhibition of blood cortisol in the 1-mg dexamethasone suppression test, and autonomous cortisol secretion was observed. Cushing’s sign of moon face, hypertension, abnormal menstruation, and glucose intolerance were observed. Based on the above, Cushing’s syndrome was diagnosed. Abdominal computed tomography showed a tumor suspected to be a left adrenal adenoma. Adsterol scintigraphy was performed, which confirmed localization of the left adrenal gland tumor, so laparoscopic left adrenalectomy was performed. In the early postoperative period, there was little improvement in cardiac morphology and hypertension persisted. The findings of cardiac hypertrophy gradually improved, and her condition had mostly normalized 2 years after the operation.

The patient was a woman in her 50s. She was referred to our department with a diagnosis of papillary thyroid carcinoma. PET-CT performed for systemic search revealed a right breast mass with FDG accumulation and multi-organ metastasis, which was suspected to be an overlapping cancer with breast cancer. On palpation, a 1-cm-sized hard elastic mass was palpated just below the right nipple. Breast ultrasonography revealed an oval hypoechoic mass with a 10-mm diameter, smooth borders, and abundant blood flow at 6:00C section depth in the right breast. A needle biopsy was performed, and although the histological type was difficult to evaluate, a diagnosis of breast metastasis from papillary thyroid carcinoma was made based on immunohistochemical examination. Surgery was scheduled, but rapid progression of the disease was observed, and a total thyroidectomy and tracheostomy were performed urgently. Postoperative pathology diagnosed the thyroid tumor as anaplastic thyroid carcinoma, and although a final pathological diagnosis of the right breast mass was not reached, the diagnosis of breast metastasis from anaplastic thyroid carcinoma was considered appropriate given the rapid outcome and the findings consistent with a metastatic tumor on imaging. Breast metastasis from malignant tumors of other organs is extremely rare, and in this case, the definitive diagnosis of a breast mass was difficult to make. In addition to the imaging features of a metastatic breast tumor, it is important to consider the imaging features of the primary tumor and make a comprehensive judgment.