3D ultrasound aids breast tumor identification
Three-dimensional (3D) power Doppler ultrasound helps radiologists distinguish between malignant and benign breast masses, according to a study published in the November issue of Radiology.

“Using 3D scans promises greater accuracy due to more consistent sampling over the entire tumor,” said the study’s lead author Gerald L. LeCarpentier, PhD, assistant professor in the department of radiology at University of Michigan in Ann Arbor. “Our study shows that 3D power Doppler ultrasound may be useful in the evaluation of some breast masses.”

Malignant breast masses often exhibit increased blood flow compared to normal tissue or benign masses. Using 3D power Doppler ultrasound, the researchers said that radiologists are able to detect vessels with higher flow speeds, which likely indicate cancer.

LeCarpentier and colleagues studied 78 women between the ages of 26 and 70 with an average age of 49 years, who were scheduled for biopsy of a suspicious breast mass. Each of the women underwent a 3D Doppler ultrasound exam followed by core or excisional biopsy of the breast.

The ultrasound exams were performed with GE Healthcare’s Logiq 700 scanner using an M12 linear-matrix-array transducer. A handheld linear position-encoding apparatus interfaced to a computer system was used to obtain parallel images and record image plane positions, which were nominally spaced 0.5 mm apart, the authors noted.

Image data was transferred to a workstation, where 3D image volumes were reconstructed from 2D image data and recorded section positions. Each 3D volume was displayed as a series of three intersecting orthogonal planes by using data visualization software, AVS/Express, from Advanced Visualization Systems.

The results showed that 3D power Doppler ultrasound was highly accurate in identifying malignant breast tumors, according to the researchers. When combined with age-based assessment and grayscale visual analysis, the investigators found that 3D Doppler showed a sensitivity of 100 percent in identifying cancerous tumors and a specificity of 86 percent in excluding benign tumors.

According to the study, flow velocity-weighted color-Doppler pixel measurements appear to be the most effective for mass characterization as compared with Doppler power measurements and mean velocities. The implication for patient care is that enhanced diagnostic performance of 3D Doppler-based multivariable indexes over grayscale ultrasound evaluation alone may possibly lead to the elimination of some biopsies.

“Using speed-weighted 3D power Doppler ultrasound, higher flow velocities in the malignant tumor-feeding vessels may be detected, whereas vessels with slower flow velocities in surrounding benign masses may be excluded,” LeCarpentier noted.