Cone-beam CT faster, potentially more accurate than mammography
Cone-beam breast CT provides exceptional tissue contrast and can potentially reduce examination time with comparable radiation dose to conventional 2D mammography, according to a new study published in the December issue of the American Journal of Roentgenology.

Researchers from the University of Texas M.D. Anderson Cancer Center in Houston, investigated the feasibility of diagnostic breast imaging using a flat-panel, detector-based, cone-beam CT system.

For the study, the researchers, using cone-beam CT on 12 mastectomy specimens with a voxel size of 145 or 290 µm, found that structured noise on cone-beam CT was minimal because of the absence of overlapping tissue. The breast anatomy was well resolved on all images as skin, adipose, and glandular regions; and the microcalcifications within cancers were clearly shown. In addition, they discovered that the detection of cancers based on morphologic assessment of tissue structures could potentially be improved compared with mammography because of the lack of overlapping glandular tissue.

“Despite the advantage of excellent spatial resolution, conventional mammography is unable to diagnose all cancers, especially early cancers in dense breasts, and cancers in high risk women such as genetic carriers,” said Wei Tse Yang, MD, lead author.

The researchers said that cone-beam CT may be used to replace mammography in screening and diagnostic breast imaging. “In addition to overcoming the problem of overlapping breast tissue, cone-beam breast CT has the ability to provide true 3D images of the breast that may help depict the 3D morphology and distribution of lesions, and that may provide incremental benefit in the differentiation of abnormalities from background breast tissue. In addition, the multiplanar high-resolution surveys it provides are at a radiation dose comparable to routine mammography,” Yang said.

Besides those benefits of cone-beam breast CT, the researchers highlighted others as well. “Scanning using this method takes less than one minute. This compares with 40 minutes for breast MRI, and 10 minutes for mammography. It also eliminates the discomfort associated with compression during mammography and the problem of claustrophobia during MRI,” Yang said.