In an effort to improve the early stage detection and diagnosis of breast cancer, a handful of research groups have been investigating the use of x-ray computerized tomographic (CT) imagers dedicated for use in imaging the breast. Preliminary results suggest that dedicated breast CT systems can provide improved visualization of 3D breast tissue as compared to conventional mammography. However, current breast CT prototypes that are being investigated have limitations in terms of detectors used, acquisition geometry and signal processing that result in less than desirable spatial resolution, lesion contrast, and signal-to-noise (SNR) ratio. These CT prototypes also measure a substantial amount of scattered radiation, and have inadequate detector coverage for breast tissue located near the chest wall. These physical limitations will prohibit current breast CT technology from providing the maximum performance in detecting and diagnosing early-stage breast cancer. The overall goal of this proposal is to develop and validate an innovative detector system and imaging methodology for improved performance in dedicated CT imaging of the breast. The CT breast imaging system that we propose herein will use semiconductor detectors operating in a photon counting mode, acquiring projections in a helical CT geometry. For over a century now, clinical x-ray imaging devices have operated in energy integrating mode, whereby images are formed by integrating x-ray events over a finite acquisition time. For a number of reasons which we outline in the proposal, the performance of energy integrating detectors are sub-optimal for use in CT imaging of the breast. However, due to the high count rate (i.e., x-ray fluence incident on the detector) typically present in x-ray CT, it has historically been impossible to operate CT detectors in a photon counting mode. Due to recent technological improvements in x-ray detectors and associated electronics, it has now become feasible for photon counting detectors to be used for breast CT applications. Simulation and modeling will be used to examine certain design specifications for such a photon- counting x-ray CT system, and a prototype will be constructed and validated by imaging breast phantoms and fresh mastectomy specimens. Using a bench-top prototype of the proposed CT imager, we will validate its performance and compare it to a conventional flat-panel CT breast imager using an indirect conversion, energy integrating detector.

Public Health Relevance

Tomographic x-ray imaging dedicated to imaging of the breast can potentially improve the detection and diagnosis of breast cancer by providing radiologists with 3D images of the breast. This research proposes to develop an improved, innovative detector system for breast CT imaging.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA140400-03
Application #
8220792
Study Section
Special Emphasis Panel (ZRG1-SBIB-P (02))
Program Officer
Zhang, Yantian
Project Start
2010-05-01
Project End
2014-02-28
Budget Start
2012-03-01
Budget End
2013-02-28
Support Year
3
Fiscal Year
2012
Total Cost
$587,977
Indirect Cost
$107,475
Name
University of Massachusetts Medical School Worcester
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
603847393
City
Worcester
State
MA
Country
United States
Zip Code
01655
Kalluri, Kesava S; Mahd, Mufeed; Glick, Stephen J (2013) Investigation of energy weighting using an energy discriminating photon counting detector for breast CT. Med Phys 40:081923
Makeev, Andrey; Glick, Stephen J (2013) Investigation of statistical iterative reconstruction for dedicated breast CT. Med Phys 40:081904
O'Connor, J Michael; Das, Mini; Dider, Clay S et al. (2013) Generation of voxelized breast phantoms from surgical mastectomy specimens. Med Phys 40:041915