Prior studies have shown that breast CT (bCT) outperforms mammography in the visualization of mass lesions, yet underperforms in the detection of micro-calcifications. The Breast Tomography Project at UC Davis has successively developed and fabricated four dedicated breast CT scanners, the most recent code-named Doheny, that produce high resolution, fully tomographic images, and overcome the tissue superposition effects of mammography at equivalent radiation dose. Over 600 patients have been imaged thus far in an ongoing clinical trial. The Doheny prototype differs from prior bCT generations in its usage of a pulsed rather than continuous x-ray source and in its utilization of a CMOS flat-panel fluoroscopic detector rather than TFT. Spatial Resolution analysis performed on Doheny indicates that the MTF characteristics have been substantially improved.
Dedicated breast CT (bCT) technology may be useful for patients with high risk of developing breast cancer. Previous
studies have shown that bCT outperforms mammography in the visualization of mass lesions, however mammography is
superior in identifying microcalcifications. The Breast Tomography Project at UC Davis has led to development of three
dedicated breast CT scanners that produce high resolution, fully tomographic images, overcoming tissue superposition
effects found in mammography while maintaining an equivalent radiation dose. Over 600 patients have been imaged in
an ongoing clinical trial. The first patient scan was performed on the latest bCT scanner developed at UC Davis, called
Cambria, on April 12, 2012. The main differences between Cambria and the previous scanners are in using a pulsed xray
source (generator and tube) instead of continuous x-ray sources, and also in using the non-binning mode of the flatpanel
fluoroscopic detector. The spatial resolution characteristics of the new scanner were investigated and the results
show significant improvement in the overall MTF properties. Based on these results, it was concluded that using the
pulsed x-ray tube, we were able to restore the MTF degradation caused by motion blurring effect that exists in previous
generations of bCT. Moreover, MTF analysis shows that using the detector in the native acquisition mode (1 x 1) results
in superior spatial resolution which will likely bring considerable improvement to the delineation of microcalcifications.