Anush Sridharan, Abstract Co-Author: Nothing to Disclose

John Robery Eisenbrey PhD, Abstract Co-Author: Nothing to Disclose

Flemming Forsberg PhD, Presenter: Equipment support, Toshiba Corporation Equipment support, Siemens AG Research collaboration, General Electric Company Research collaboration, Ultrasonix Medical Corporation Research collaboration, Toshiba Corporation Advisory Board, Siemens AG Advisory Board, Toshiba Corporation

Priscilla Machado MD, Abstract Co-Author: Nothing to Disclose

Daniel Arthur Merton, Abstract Co-Author: Nothing to Disclose

Kirk Wallace PhD, Abstract Co-Author: Employee, General Electric Company

Carl Chalek PhD, Abstract Co-Author: Employee, General Electric Company

Kai E. Thomenius PhD, Abstract Co-Author: Employee, General Electric Company

To develop a method for improving visualization of vascularity in breast lesions using 3D contrast-enhanced subharmonic imaging (SHI).

A modified Logiq 9 (GE Healthcare, Milwaukee, WI) scanner with a 4D10L probe was used for 3D harmonic imaging (HI) and SHI of breast lesions in 72 patients after bolus injection of an ultrasound contrast agent (UCA; Definity, Lantheus Medical Imaging, N Billerica, MA; dose: 0.25mL for HI and 20μL/kg for SHI). Fifteen biopsy-proven malignant cases were selected for image processing. A region-of-interest (ROI) corresponding to UCA flow (within the lesion) and tissue in both 3D HI and SHI were selected for each case. A volumetric map of the time-intensity curve for each slice within the volume was generated over time. Slices showing presence of UCA were identified and isolated. To improve visualization of flow a volumetric background template was generated (from baseline) and used to filter out tissue signals. Contrast-to-tissue ratios (CTR’s) were calculated for 3D HI and SHI before and after background subtraction for vessel-tissue ROIs and also compared between the isolated slices and the entire volume.

Both 3D HI and SHI showed significant suppression of tissue signal after background filtering (p<0.002). The level of tissue suppression was comparable between HI and SHI (72% vs. 77%, respectively). However, given that the inherent tissue suppression in SHI was significantly (p<0.001) higher than HI pre background filtering, the isolation of vasculature (i.e., UCA flow) in SHI post filtering was ~7.5 times greater compared to HI, although not significant (p=0.15) given the large variability between cases and small sample size (n=15). The vessel-tissue CTR was significantly higher for isolated slices in 3D SHI (p=0.02), but no significant improvements were seen in 3D HI (p=0.78).

3D SHI showed better visualization of vasculature in all cases via increased tissue suppression and sensitivity to UCA flow. The improvement in visualization of vasculature based on isolation of slices demonstrates the importance of 3D imaging to visualize breast cancer flow.

Visualizing the vascular structure of breast lesions may help improve characterization.

Sridharan, A, Eisenbrey, J, Forsberg, F, Machado, P, Merton, D, Wallace, K, Chalek, C, Thomenius, K, Visualization of Vascularity in Breast Lesions Using US Contrast Enhanced 3D Subharmonic Imaging.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13026054.html