| Autor: |
P.N. Burns, P. L. Hilpert, B.B. Goldberg |
| Rok vydání: |
2005 |
| Předmět: |
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| Zdroj: |
[1990] Proceedings of the Twelfth Annual International Conference of the IEEE Engineering in Medicine and Biology Society. |
| DOI: |
10.1109/iembs.1990.691097 |
| Popis: |
A new contrast agent capable of traversing pulmonary and cardiac circulations was used to create echo enhancement from arterial blood following peripheral-venous injection. In vivo dose-response measurements for this agent were made by analysis of Doppler signals acquired directly from systemic vessels and tumor tissue. Ten woodchucks with naturally occurring hepatomas were studied using duplex scanning and lOMHz pulsed Doppler transducers positioned surgically on the tumor, portal and celiac vessels. 0.05lmVkg injections of 3.5~ air-filled albumin microspheres (AlbnnexTM) were made into a peripheral vein. Signal enhancement was computed using digital frequency domain methods. Angiographic correlation was obtained in three animals. A 7dB enhancement of systemic arterial signals was measured at the lowest dose of 0.05mVkg. Signal enhancement rose monotonically but non-linearly to 20dB at ImVkg. No effect was detected from saline control injections or from cumulation of consecutive injections. A maximum 13dB was measured in the tumor signals. No enhancement was detected from portal venous blood. It is concluded that the intravenous use of an ultrasound contrast agent is capabl e of lowering the threshold of detectability of tumor and tissue vascularization using conventional Doppler instruments. Enhancement originates from hepatic arterial supply. Intravenous ultrasound contrast agents therefore hold promise for radiologic diagnosis. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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