Ultrasound examination is performed on all patients with thyroid tumors. Papillary carcinoma of the thyroid presents typical malignant findings on ultrasonography:, irregular shape, jagged border, low echogenic and heterogeneous internal echo, small and multiple high echoic spots, and lymph node swelling. Some variants of papillary carcinoma present specific findings on ultrasonography. The encapsulated variant of papillary carcinoma presents benign findings, while the diffuse sclerosing variant presents tumor non-forming findings on ultrasonography. Differential diagnosis of follicular carcinoma from follicular adenoma is difficult. Malignant lymphoma presents characteristic findings of very low internal echo and attenuation of posterior echo. Findings of adenomatous goiter, adenomatous nodule, and cyst are explained as are indications for surgery or observation, and selection of the portion of nodules for cytolygic examination.

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Purpose: To compare the length of microbubble (MB) collapse of liver parenchyma brought about by repeated strong pulses in the post-vascular phase (Kupffer phase) of Sonazoid^® enhanced ultrasonography with ablation zone radiofrequency ablation (RFA) in patients with hepatocellular carcinoma. Subjects: This study was performed on 48 nodules of 48 patients with viral chronic hepatic diseases who had undergone RFA treatment using 20-mm cool-tip needles for HCC from January 2008 through December 2009. Methods: Ultrasonography with Sonazoid^® was carried out before RFA. The post-vascular phase (Kupffer phase) MB within the right hepatic lobe were collapsed by a flash-replenishment sequence 10 minutes after initiation of ultrasonography, and the length of the collapse was measured from the hepatic surface. RFA treatment was then performed and the ablation zone was measured by computed tomography (CT) after treatment and compared with the length of the collapse. Moreover, length of collapse was compared with various markers of hepatic fibrosis. Results: The width of the RFA ablation zone decreased significantly with increase in length of collapse (P=0.0001). Further, IV type collagen 7S increased significantly with length of MB collapse, suggesting a possible role of hepatic fibrosis in the length of collapse. Conclusion: The width of the RFA ablation zone decreased with increase in the length of post-vascular phase (Kupffer phase) MB collapse after ultrasonography with Sonazoid^®. This method is useful for estimating the ablation zone before RFA.

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A 50-year-old man was referred to this institution in August 2009 for further diagnostic evaluation of a mitral valve tumor. Transthoracic echocardiography performed at the previous hospital in December 2004 revealed a 4 mm mass attached to the mitral valve. Tumor size gradually increased, and transthoracic echocardiographic examination at time of admission to our hospital showed a 10 x 13 mm mobile spherical tumor attached to the posterior mitral leaflet, on the left atrial side of the middle scallop (P2). The margins were relatively regular, but were in a fluffing state in the extended image. The stalk of the tumor was not demonstrated, and no mitral valve regurgitation or valve stenosis was noted. Transesophageal echocardiography (TEE) showed an echolucent area in the tumor, and the tumor surface tumor was uneven. Three-dimensional TEE confirmed that the motion of the mitral valve did not affect the tumor. Because of the risk of thromboembolism, however, the tumor was completely removed surgically. The histological examination supported a definite diagnosis of papillary fibroelastoma. We report this as a case in which increase in tumor size was detected by echocardiography during a follow-up period of 5 years.

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Intussusception of the stomach can result from a tumor or from surgery. Although both gastroduodenal and gastrojejunal intussusception are known, gastrogastric intussusception is rare. We encountered a case of gastrogastric intussusception resulting from an unusually large hyperplastic polyp in a 54-year old woman. The characteristic multiple concentric ring sign was observed on ultrasonography. Computed tomography revealed an unusually large gastric polyp. The ultrasound longitudinal scan showed the typical multiple concentric ring and Hay-Fork signs indicative of a gastrogastric intussusception produced by a 40-mm polypoidal mass in the gastric antrum. With this diagnosis, endoscopic submucosal dissection was carried out and the histologic examination identified an unusually large hyperplastic polyp. These ultrasonographic signs are characteristic in gastrogastric intussusception, and ultrasonography proved useful in reaching this diagnosis.

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Radical resection may provide a favorable prognosis for patients with gallbladder carcinomas with only shallow subserosal invasion (<=2mm: shallow pT2), and use of ultrasound imaging to confirm in these cases has attracted much attention. On the other hand, depth of invasion in the related bile duct carcinomas remains difficult to determine. Although an ultrasound imaging of early bile duct carcinoma has been reported recently, no ultrasound images of shallow pT2 bile duct carcinomas have hitherto appeared. Here we document our experience with one such case, in which ultrasound depicted a swollen gallbladder and a dilated bile duct with a tumor. Magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiography (ERC) revealed an irregularly narrowed middle-to-superior bile duct, although additional intraductal ultrasonography demonstrated a tumor occupying the middle bile duct with no irregularity in the outermost hyperechoic layer. Under the diagnosis of early bile duct carcinoma, cholecystectomy and extirpation of the bile duct were carried out. Intraoperative ultrasonography showed a tumor at the junction of cystic duct and a thickened outermost hyperechoic layer with a worm-eaten area. Histopathology showed a 19×17 mm shallow pT2 bile duct carcinoma (pap>tub1 with pN0). Further studies should attempt to confirm the suitability of ultrasound in diagnosing cases with a thickened outermost hyperechoic layer in shallow pT2 bile duct carcinoma.

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