Development and Spatial Resolution Characterization of A Dedicated Pulsed X-Ray, Cone-Beam Breast Ct System

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 x-ray source (generator and tube) instead of continuous x-ray sources, and also in using the non-binning mode of the flat-panel 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.