Biomaterial Database

Comparison of contrast-enhanced fundamental imaging, second-harmonic imaging, and pulse-inversion harmonic imaging. 2001

A Y Kim, and B I Choi, and T K Kim, and K W Kim, and J Y Lee, and J K Han

Department of Radiology at Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

OBJECTIVE To investigate the feasibility of recent contrast-specific ultrasound techniques in depicting vascular flow and the effects of changing the output power of the transducer and insonation mode on contrast enhancement, the authors performed an experimental study with a flow phantom. METHODS While changing the mechanical index and the sound insonation mode (continuous and intermittent), images were obtained with three contrast-enhanced ultrasound techniques: fundamental, second-harmonic, and pulse-inversion harmonic imaging (PIHI) after a bolus injection of microbubble contrast agent. The images were compared on a time-intensity curve. RESULTS In assessing fixed flow (10 cm/s), PIHI showed the best depiction of flow signal. In intermittent scanning, increases in the mechanical index caused stronger flow signals and longer enhancement duration in all techniques. However, continuous scanning revealed poor depiction of flow signal regardless of the technique or changes in the mechanical index because of significant bubble destruction. CONCLUSIONS Microbubble-enhanced PIHI with intermittent scanning at a high mechanical index can depict vascular flow highly effectively without shortening the duration of enhancement.

UI	MeSH Term	Description	Entries
D011134	Polysaccharides	Long chain polymeric CARBOHYDRATES composed of MONOSACCHARIDES linked by glycosidic bonds.	Glycan,Glycans,Polysaccharide
D001783	Blood Flow Velocity	A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.	Blood Flow Velocities,Flow Velocities, Blood,Flow Velocity, Blood,Velocities, Blood Flow,Velocity, Blood Flow
D003287	Contrast Media	Substances used to allow enhanced visualization of tissues.	Radiopaque Media,Contrast Agent,Contrast Agents,Contrast Material,Contrast Materials,Radiocontrast Agent,Radiocontrast Agents,Radiocontrast Media,Agent, Contrast,Agent, Radiocontrast,Agents, Contrast,Agents, Radiocontrast,Material, Contrast,Materials, Contrast,Media, Contrast,Media, Radiocontrast,Media, Radiopaque
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014463	Ultrasonography	The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.	Echography,Echotomography,Echotomography, Computer,Sonography, Medical,Tomography, Ultrasonic,Ultrasonic Diagnosis,Ultrasonic Imaging,Ultrasonographic Imaging,Computer Echotomography,Diagnosis, Ultrasonic,Diagnostic Ultrasound,Ultrasonic Tomography,Ultrasound Imaging,Diagnoses, Ultrasonic,Diagnostic Ultrasounds,Imaging, Ultrasonic,Imaging, Ultrasonographic,Imaging, Ultrasound,Imagings, Ultrasonographic,Imagings, Ultrasound,Medical Sonography,Ultrasonic Diagnoses,Ultrasonographic Imagings,Ultrasound, Diagnostic,Ultrasounds, Diagnostic
D018608	Ultrasonography, Doppler	Ultrasonography applying the Doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. (Stedman, 25th ed)	Doppler Ultrasonography,Doppler Ultrasound,Doppler Ultrasound Imaging,Doppler Ultrasound Imagings,Doppler Ultrasounds,Imaging, Doppler Ultrasound,Imagings, Doppler Ultrasound,Ultrasound Imaging, Doppler,Ultrasound Imagings, Doppler,Ultrasound, Doppler,Ultrasounds, Doppler
D019047	Phantoms, Imaging	Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)	Phantoms, Radiographic,Phantoms, Radiologic,Radiographic Phantoms,Radiologic Phantoms,Phantom, Radiographic,Phantom, Radiologic,Radiographic Phantom,Radiologic Phantom,Imaging Phantom,Imaging Phantoms,Phantom, Imaging