Comparison of Tissue Harmonic Imaging with Conventional US in Abdominal Disease1

• Published in: Radiographics Vol. 20; no. 4; p. 1127
• Main Authors: Sabina Choudhry, Brian Gorman, J. William Charboneau, Donald J. Tradup, Rebecca J. Beck, James M. Kofler, Debra S. Groth
• Format: Journal Article
• Language: English
• Published: Radiological Society of North America 01-07-2000
• ISSN: 0271-5333; 1527-1323

Harmonic waves are generated from nonlinear distortion of an acoustic signal as an ultrasound wave insonates tissues in the
body. These beams are integer multiples of a fundamental transmitted frequency. Potential advantages of harmonic imaging include
improved axial resolution due to higher frequencies and better lateral resolution due to narrower beams. Decreased noise from
side lobes improves signal-to-noise ratios and reduces artifacts. Deleterious effects of the body wall are also reduced. The
authors prospectively studied ultrasonographic (US) findings in 100 adult patients with 202 abdominal lesions by comparing
harmonic US images with conventional US images. The results were subjected to statistical analysis. Harmonic imaging was superior
to conventional US in regard to lesion visibility and diagnostic confidence. Harmonic imaging was particularly useful for
depicting cystic lesions and those containing echogenic tissues such as fat, calcium, or air. In patients with a body mass
index of 30 or more, harmonic imaging was clearly better for lesion visibility and confidence of diagnosis. The authors recommend
routine use of harmonic imaging for abdominal US studies in all adult patients.