Transesophageal Ultrasonic Imaging of the Heart
In echocardiology ultrasound backscattering is used to visualize heart structures. The various realtime cardiac scanners give detailed dynamic pictures of the moving boundaries of cardiac anatomy [1, 2, 3, 4]. The intensity of ultrasonic backscattering from within the myocardial tissue may vary with the normal and ischemic status of the heart tissue [5, 6]. Balasubram-anian Rajagopalan, et al.,  first reported that regional myocardial perfusion could be imaged using ultrasonic backscattering when suitable contrast agents were arterially introduced. Using a 10 MHz high resolution B-scanner that was placed directly on the surface of the heart of anesthetized dog after a left thoracotomy, the authors showed that the backscattering from the myocardial mass was enhanced significantly if an ultrasound contrast agent such as indocyanine green was injected into the left ventricle or at the aortic root. This enhancement of backscattering was observed to be related to regional blood flow since after deprivation of blood supply to a region of the myocardium, the intensity of backscattering from the deprived region did not exhibit enhancement with the injection of the contrast agent.
KeywordsMitral Valve Aortic Root Indocyanine Green Ultrasonic Transducer Ultrasound Contrast Agent
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- 1.Kloster, F. E., J. Roelandt, F. J. Ten Cate, N. Born, and P. G. Hugenhotz: Multiscan echocardiography. II Techniques and initial clinical results. Circulation 48:1075–1084, 1973.Google Scholar
- 2.Griffith, J. M., and W. L. Henry: A sector scanner for real-time two-dimensional echocardiography. Circulation 49:1147–1152, 1974Google Scholar
- 3.Kisslo, J., O. T. Van Ramm, and F. L. Thurstone: Cardiac imaging using a phased array ultrasound system. II. Clinical technique and application. Circulation 53:262–267, 1976.Google Scholar
- 4.Tajik, A. J., J. B. Seward, D. J. Hagler, D. D. Mair, and J. T. Lie: Two-dimensional real-time ultrasonic imaging of the heart and great vessles: Technique, image orientation, structure identification, and validation. Mayo Clinic Proceedings 53:271–303, 1978.Google Scholar
- 5.Balasubramanian Rajagopalan and J. F. Greenleaf: 1977 Unpublished results.Google Scholar
- 6.O’Donnell, M., D. Bauwens, J. W. Mimbs, and J. G. Miller: In vivo detection of acute myocardial ischemia in the dog by quantitative ultrasonic backscatter. Fourth International Symposium on ultrasonic imaging and tissue characterization, June 18-20, Gaithersburg, Maryland.Google Scholar
- 7.Balasubramanian Rajagopalan, J. F. Greenleaf, P. A. Chevalier, and R. C. Bahn: Myocardial blood flow: visualization with ultrasonic contrast agents. Acoustical Imaging 8:719–729, 1980, edited by A. F. Metherell. Plenum Publishing Corporation.Google Scholar
- 8.Buxton, J., E. DiMagno, D. Wilson, J. Suarez, P. Regan, R. Hattery, and P. Green: Initial results in the development of an ultrasonic endoscope. Proceedings of the 24th Annual Meeting of AIUM, 1:121, 1979.Google Scholar
- 9.DiMagno, E. P., J. L. Buxton, P. T. Reagan, R. R. Hattery, D. A. Wilson, J. R. Suarez, and P. S. Green: Canine intragastroesophageal ultrasonography. Clinical Research 27:628A 1979.Google Scholar
- 10.DiMagno, E. P., J. L. Buxton, P. T. Reagan, R. R. Hattery, D. A. Wilson, J. R. Suarez, and P. S. Green: The Ultrasonic Endoscope (Lancet — to be published).Google Scholar
- 12.Hisanaga, K., and A. Hisanaga: A new transesophageal radial scanner using a rotating flexible shaft and initial clnical results. Proceedings of the 24th Annual Meeting of the AIUM, 1:122, 1979.Google Scholar
- 13.Tyler, T. D., A. H. Gobuty, J. Shewmaker, and N. F. Maklad: In vivo quantitation of induced ultrasonic contrast effects in the mouse. Ninth International Symposium on Acoustical Imaging, December 3-6, 1979, Houston, Texas. Acoustical Imaging, Vol. 9. Plenum Press.Google Scholar