Semi-quantitating Stiffness of Breast Solid Lesions in Ultrasonic Elastography

Rationale and Objectives

To explore whether strain ratio measurement could semi-quantitatively evaluate the stiffness of breast lesions.

Materials and Methods

From January 2008 to May 2008, 148 patients with 254 solid lesions (183 benign, 71 malignant) in the breast were included in the study. Ultrasound sonography found the lesions and ultrasonic elastography obtained the strain images. By using the strain ratio measurement method together with the ultrasound machine, the strain index of the lesion was calculated. Different depths of breast tissue were selected as the reference. The strain indexes of malignant and benign solid lesions were calculated with the same level of breast tissue as the reference.

Results

The strain indexes of breast lesions were different compared to the same depth of breast tissue and the superior level of fat tissue (P = 0.000). The strain indexes of breast lesions were different compared to different depths of breast glandular tissues (P = 0.003). At the same level of the breast lesions, 212 lesions were glandular tissue, 11 were fat tissue, and 40 were both. In the lesion plane, six lesions had almost no glandular tissue and 20 had almost no superior fat tissue. Compared to the same depth of breast tissue, the strain indexes of benign lesions (range, 0.62–11.07) and malignant lesions (range, 3.12–39.28) were different (P = 0.000).

Conclusion

Using the strain ratio measurement, stiffness of breast lesions could be semi-quantitated with the same depth of breast tissue as the reference. This method may provide another diagnostic method in addition to the 5-point scoring system used with ultrasonic elastography in the future.

Key Words: Ultrasonic elastography, breast lesion, stiffness