摘要:

SummaryContrast agents enhance ultrasound by changing the ultrasound signal from within the body. Such agents can be introduced directly into body cavities or injected intravenously. The overwhelming number of agents under development utilize gas microbubbles to produce contrast. One agent has been approved for use in echocardiography and a number of agents are in clinical trials in the United States for virtually all types of ultrasound examinations. Agents that are injected intravenously can enhance the spectral and color Doppler in systemic vessels for several minutes. In preliminary trials, agents seem to be well tolerated. Gray scale enhancement of the cardiac chambers and myocardium is detectable with some agents and gray scale changes in other organs have been seen in animals and in preliminary human trials. Contrast has been shown to reduce the number of sub-optimal studies necessary for abdominal and peripheral circulations, increase diagnostic confidence, and increase detection of tumor neovascularity. Newer agents under development are being targeted for uptake by certain organs, e.g., liver, or by tumors. Newer instumentation, which allows harmonic imaging, may be a novel means by which to detect and display contrast agents. Injectable contrast agents offer potentially unique improvements to ultrasound.

ISSN:0894-8771    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

SummaryEndoscopic ultransonography (EUS) provides an almost histologic visualization of the gastrointestinal wall. Consequently, it has been demonstrated to be superior to other imaging modalities in determining the T stage of malignancies of the GI tract. As such, it is instrumental in the stage-dependent pretreatment evaluation of these malignancies. EUS is the examination of choice to evaluate submucosal masses of the GI tract, preventing the biopsy of normal or vascular structures. An overview of EUS of the esophagus, stomach, pancreas, biliary system, colon, and rectum is presented.

ISSN:0894-8771    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

SummaryCongenital brain anomalies are usually both complex and multiple. The diagnosis of these conditions requires an understanding of embryology and knowledge of the effects of these embryologic disturbances on the brain parenchyma and ventricles. Ultrasonography is usually the primary imaging examination in neonates with suspected intracranial malformations. This review describes the spectrum of sonographic findings associated with congenital brain anomalies.

ISSN:0894-8771    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0894-8771    

出版商:OVID    

年代:1995

数据来源: OVID