Most pancreatic neoplasms show a grossly characteristic cut surface, and the macroscopic findings can identify the histological type. Transabdominal or endoscopic ultrasound provides a clear image reflecting the tumor cut surface, and this modality is useful for differentiating pancreatic neoplasms. Ultrasound can classify pancreatic neoplasms into three types: solid, cystic, and mixed tumors. It is important to evaluate the shape, margin, internal echo, and posterior echo. An invasive or expansive growth pattern, tumor thrombus into the main pancreatic duct or portal venous system, and intratumoral flow signals in Doppler mode are useful information for narrowing down the differential diagnosis. On the basis of evaluation of macroscopic and microscopic findings of pancreatic neoplasms, we explain characteristic ultrasound findings for the purpose of differential diagnosis.

Ultrasonography is a minimally invasive imaging modality used in routine clinical practice. No special environment is needed to perform this examination; therefore, it is widely used by urologists to perform comprehensive medical examinations and mass screenings, among other such procedures. Ultrasonography is an effective screening modality for early detection of renal cancer. A renal examination should include close observation of the size and shape of the kidneys and the echogenicity of the renal cortex and medulla. Clinicians should also carefully assess renal sinus abnormalities, as well as the presence of tumors. This paper describes the fundamental concepts and knowledge required for beginners to perform ultrasonographic examinations. Details regarding probe scanning methods, specific points requiring close observation, and the typical conditions clinicians encounter in routine clinical practice are summarized. This article provides an overview of each of the following conditions: congenital anomalies (horseshoe kidneys among other such abnormalities), kidney failure, pyelonephritis, urinary calculi, cystic disease, and neoplastic lesions (angiomyolipoma, renal cell carcinoma).

As high-frequency ultrasound transducers have become readily available in recent years, ultrasound imaging is being adopted widely in the field of dermatology. As an introduction to ultrasound imaging in the field of dermatology, I describe the characteristics of benign tumors, such as epidermal cysts (atheromas), calcifying epitheliomas, lipomas, and foreign body granulomas, on ultrasound. Specifically, I discuss characteristics that help distinguish inflammatory epidermal cysts from normal cysts, as well as trichilemmal cysts and dermoid cysts from epidermal cysts. Ultrasound imaging can also be used to characterize calcifying epitheliomas as the degree of calcification affects ultrasound images, and help diagnose conditions that involve proliferation of adipocytes, including lipomas, angiolipomas, and nevus lipomatosus cutaneous superficialis. I describe the clinical findings, ultrasound characteristics, and pathological findings of common benign subcutaneous tumors.

An 82-year-old male with paroxysmal atrial fibrillation was referred to our hospital for catheter ablation therapy. Transthoracic echocardiography (TTE) showed a dilated coronary sinus (CS), and there appeared to be a communication between the CS and the left atrium (LA) in the two-chamber view, suggestive of unroofed coronary sinus (UCS), but right-sided chambers were not dilated. Transesophageal echocardiography (TEE) was performed for a detailed investigation. Intravenous agitated saline contrast echocardiography through the left upper arm could not identify a persistent left superior vena cava. Three-dimensional transesophageal echocardiography (3D-TEE) revealed a direct communication between the terminal portion of the CS and LA through the deficit hole with a diameter of 15 mm. Moreover, the CS ostium was covered with a fenestrated membranous structure and stenosed. We diagnosed UCS with CS ostial stenosis. The CS ostial stenosis likely restricted the left-to-right shunt flow, preventing remarkable right heart volume overload. 3D-TEE was useful for evaluation of the structure of UCS and CS ostial stenosis.

A cystic nodule, 15 mm in diameter, was detected by ultrasonography (US) in the S4 segment of the left hepatic lobe in a 78-year-old male who achieved eradication of hepatitis C virus and was undergoing regular US surveillance every 6 months. A solid nodule, 8 mm in diameter, was found in this cystic nodule 20 months after detection of the cystic nodule and was subjected to further evaluation. A solid part was enhanced in the arterial phase of contrast-enhanced US (CEUS), whereas the imaging evaluation of this solid nodule was difficult by computed tomography or magnetic resonance cholangiopancreatography due to its minute size. The B4 bile duct was not depicted by endoscopic retrograde cholangiography (ERC), but intraductal US (IDUS) from the B2＋3 bile duct depicted a hyperechoic nodule at the proximal site of the B4 branch. CEUS and ERC findings of this nodule suggested intraductal papillary neoplasm of the bile duct (IPNB), and the left hepatic lobe and the caudate lobe were resected surgically. Macroscopic examination of the resected specimen revealed a multilocular lesion including a papillary nodule, and the pathologic diagnosis was papillary adenocarcinoma without interstitial infiltration. The morphology of tumor cells was similar to that of gastric epithelium, and therefore we diagnosed this nodule as gastric IPNB. This case showed that US surveillance was useful for the detection of cystic and solid nodules in an early stage. Moreover, CEUS provided useful findings for an accurate diagnosis of IPNB.

A man in his 50s was admitted to our hospital with left lower back pain. Ultrasonography (US) showed a hypoechoic area on the left side from the infrarenal abdominal aorta to the right common iliac artery. Soft tissue thickening around the artery was confirmed by delayed phase contrast-enhanced computed tomography. The serum IgG4 level was elevated at 235 mg/dl. We suspected IgG4-related periaortitis/periarteritis and started steroid therapy. The symptom subsequently improved and the hypoechoic area gradually reduced. US was a useful modality for the diagnosis and follow-up treatment of IgG4-related periaortitis/periarteritis.

Purpose: We aimed to investigate whether a smartphone-type ultrasound device could be used to satisfactorily evaluate bladder capacity. Subjects and Methods: Forty-four cases in which urological ultrasonography examination was requested were included in the study and patient consent was obtained. A smartphone-type ultrasound device was used by a sonographer to measure the transverse, vertical, and anteroposterior diameters of the bladder. Next, the same dimensions were measured using a high-performance ultrasound device that was operated by another sonographer who was blinded to the results obtained using the smartphone-type ultrasound device. The bladder capacity was calculated using the following formula: (transverse diameter × vertical diameter × anteroposterior diameter) × 0.52. Results and Discussion: The correlation coefficient of the bladder capacity measured by the smartphone-type ultrasound device and high-performance ultrasound device was high (R＝0.851). However, in cases in which the entire bladder could not be visualized owing to the small viewing angle, differences in measurement values between the high-performance ultrasound device and smartphone-type ultrasound device were observed. Conclusion: The smartphone-type ultrasound device has an accuracy equivalent to that of a high-performance ultrasound device in bladder capacity measurement. This can be utilized in medical practice outside hospitals, such as in home medical care for urination care.