Ultrasonographic examination (US) is a useful diagnostic imaging procedure. However, it requires a high level of medical knowledge and technical skill of the examiner. Examiners may miss significant findings in an ultrasonic image unless they are familiar with both normal and abnormal images. Because of their divergent nature, the examiner must possess broad extensive medical knowledge of blood vessels, urinary systems, and gynecological organs to arrive at an accurate diagnosis of acute abdominal disorders of the gastrointestinal tract. Yet, ultrasonography is only one of a battery of diagnostic tests. The final diagnosis will often require findings from other imaging modalities as well. Accordingly, the ultrasonographic study of acute abdomen requires that the examiner should be able to identify abnormal findings precisely and to report them accurately.

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The advantage of endoscopic ultrasonography (EUS) is its high resolution and its superior capacity for local observation. It is one of the most accurate diagnostic methods, particularly for the pancreatobiliary region, while advances in various imaging diagnostic methods are seen today. Since it is most useful for diagnosing small lesions, its use for early diagnosis of pancreatobiliary cancer is anticipated. However, the operating techniques are difficult, and education and training of operators has been a challenge. With the aim of solving this problem, standard imaging techniques in the pancreatobiliary region using radial scanning EUS have been established in Japan and published internationally. On the other hand, EUS guided fine needle aspiration is now coming into wide use in Japan, though the practice is behind that in Western countries. Consequently, pathological diagnosis has been made possible in addition to imaging diagnosis, and application of the techniques to treatment is also progressing. As EUS provides much information, it will be necessary to foster a large number of operators.

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Before a galactose-based microbubble ultrasound contrast agent (Levovist^®) became available, ultrasound contrast agents for enhancing tumors used carbon dioxide microbubbles. Now, Levovist^® is used in various organs including kidney, urinary bladder, and prostate in the field of urology, and its usefulness has been reported. It is used for the diagnosis of renal function by enhancing small normal blood vessels. Also, pathological changes in blood vessels are diagnosed by enhancing abnormal vessels. Furthermore, it is applied to spread of neoplastic lesions and is used for the differential diagnosis between benign or malignant tumors. Moreover, its usefulness in hemodialysis patients has also been reported. The blood-flow distribution and tumor itself in the case of renal-pelvic or ureter tumors are also enhanced, although the blood-flow of these tumors is not revealed by color Doppler. It is used for judging the clinical stage of bladder cancers after these cancers are diagnosed by ultrasonography. Moreover, the vesicoureteral reflux is diagnosed easily by ultrasonography using the contrast agent. The sensitivity and specificity are the same as voiding-vesicourethrography using an iodine contrast agent. The ultrasound contrast agent will be used for the diagnosis and follow-up of vesicoureteral reflux patients. As the vessels in prostate cancer are enhanced, the tumor sites are seen clearly, and the sensitivity in the case of prostate cancer increases by using the ultrasound contrast agent at prostate biopsy. However, early prostate cancers also have many small tumor sites several mm in size. Therefore, an increase in specificity for cancer detection is not gained by using enhancement. It is expected that effective use of the ultrasound contrast agent will increase the positive rate of prostate biopsy and lessen the number of biopsy sites.

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Purpose: We aimed to identify the electrical stimulation sites of pacemaker leads using a tissue tracking method of tissue Doppler imaging. Methods: The study group consisted of 30 patients who had undergone permanent pacemaker implantation. During tissue Doppler imaging, the initial contraction site was seen as a red area stimulated by the pacemaker lead. This red area was analyzed precisely using time-distance curves generated by tissue tracking. Results: The initial contraction site of the myocardium was located in the interventricular septum in seven patients and in the apical portion of the right ventricle in 11 patients. Furthermore, analysis of time-distance curves demonstrated that one point within the red area started to move earlier than the others. Conclusion: The site of electrical stimulation within the myocardium can be determined from the time-distance curves generated by the tissue tracking method.

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Cesarean scar pregnancy causes uterine rupture and hemorrhage. If diagnosed early, treatment options are capable of preserving the uterus and subsequent fertility. In this center, early diagnosis is achieved by transvaginal scan. Upon decreasing the blood human chorionic gonadotropin (hCG) level by methotrexate (MTX), and uterine artery embolism (UAE), we were able to remove pregnancy tissue with little blood loss by dilatation and curettage (D&C) in many cases. We encountered a case in which we were not able to remove pregnant tissue by D&C, despite having decreased the blood hCG level. A 31-year-old woman, gravida 2, para 1, had a history of lower segment cesarean section. Eight-week missed abortion was diagnosed and D&C performed at another hospital, but the procedure was terminated with insufficient treatment, due to massive blood loss. She left that hospital after the operation, although the hemorrhage continued. Afterwards, she was admitted to our hospital for diagnosis of a pre-shock state. At admission, blood hCG level was 387 mIU/m. A transvaginal scan confirmed that a mass suspected of being pregnancy tissue with abundant blood supply was a caesarean scar. Cesarean scar pregnancy was diagnosed, and systemic MTX was administered resulting in a decrease in blood hCG level to 142 mIU/ml. We attempted to remove the pregnancy tissue by D&C with uterine artery embolism. However, the procedure was not successful, because the cesarean scar was very thin, and there was a possibility of uterine perforation. Afterwards, the mass got smaller, and the blood supply for the pregnancy tissue vanished. However, bleeding continued. Laparotomy was done 13 days after D&C. The cesarean scar adhered to the bladder, and the uterine muscle layer was very thin. After we lysed the adhesions between the bladder and the uterus, the pregnancy tissue was resected via a vertical incision into the anterior wall of the lower uterine segment, and the uterine defect was repaired. We examine the medical guidelines for cesarean scar pregnancy and the Doppler ultrasound findings in this case.

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