Contribution of tissue harmonic imaging and frequency compound imaging in interventional breast sonography

The purpose of this study was to retrospectively compare conventional imaging, frequency compound imaging (CI), and tissue harmonic imaging (THI) in interventional breast sonography.

Institutional Review Board approval and patient informed consent were not required. The authors reviewed 104 sonographically guided breast procedures in 83 patients. For each biopsy, 4 images obtained with conventional imaging, frequency CI at 10 and 14 MHz (CI10 and CI14), and THI were graded independently by 2 radiologists for lesion conspicuity, needle conspicuity, lesion and needle conspicuity, and overall image quality. Frequency CI at 10 MHz, CI14, and THI were compared with conventional imaging. Different clinical scenarios (fatty versus glandular background, fine needle versus core needle, and oblique versus horizontal needle direction) were evaluated.

Statistical analysis showed that for overall image quality, CI10 was the best setting (odds ratios [OR], 3.67 and 7.48). For lesion conspicuity, CI14 (OR, 3.55) and THI (OR, 1.77) improved lesion visibility in a fatty background, whereas THI (OR, 0.26) was very limited in a glandular background. For needle conspicuity, no setting was better than conventional, whereas THI was the least valuable setting (OR, 0.011 and 0.049). For lesion and needle conspicuity, CI10 showed significantly better results than conventional for a dense background (P = .0268 and .4028; OR, 2.435 and 1.383) with 1 reviewer, whereas THI was the least valuable setting (OR, 0.014 and 0.042).

Conventional imaging provided the best assessment of lesion and needle conspicuity. Frequency compounding is a useful setting for dense breast and for fine-needle aspiration. Tissue harmonic imaging has a role in the visualization of a lesion against a fatty background but is of limited value in needle visualization.