An object-specific and dose-sparing scatter correction approach for a dedicated cone-beam breast CT system using a parallel-hole collimator

Kai Yang; George Burkett Jr.; John M. Boone

doi:10.1117/12.911093

23 February 2012 An object-specific and dose-sparing scatter correction approach for a dedicated cone-beam breast CT system using a parallel-hole collimator

Kai Yang, George Burkett Jr., John M. Boone

Author Affiliations +

Proceedings Volume 8313, Medical Imaging 2012: Physics of Medical Imaging; 831303 (2012) https://doi.org/10.1117/12.911093
Event: SPIE Medical Imaging, 2012, San Diego, California, United States

Abstract

X-ray scatter is a common cause of image artifacts for cone-beam CT systems due to the expanded field of view and degrades the quantitative accuracy of measured Hounsfield Units (HU). Due to the strong dependency of scatter on the object being scanned, it is crucial to measure the scatter signal for each object. We propose to use a beam pass array (BPA) composed of parallel-holes within a tungsten plate to measure scatter for a dedicated breast CT system. A complete study of the performance of the BPA was conducted. The goal of this study was to explore the feasibility of measuring and compensating for the scatter signal for each individual object. Different clinical study schemes were investigated, including a full rotation scan with BPA and discrete projections acquired with BPA followed by interpolation for full rotation. Different sized cylindrical phantoms and a breast shaped polyethylene phantom were used to test for the robustness of the proposed method. Physically measured scatter signals were converted into scatter to primary ratios (SPRs) at discrete locations through the projection image. A complete noise-free 2D SPR was generated from these discrete measurements. SPR results were compared to Monte Carlo simulation results and scatter corrected CT images were quantitatively evaluated for "cupping" artifact. With the proposed method, a reduction of up to 47 HU of "cupping" was demonstrated. In conclusion, the proposed BPA method demonstrated effective and accurate objectspecific scatter correction with the main advantage of dose-sparing compared to beam stop array (BSA) approaches.

Citation Download Citation

Kai Yang, George Burkett Jr., and John M. Boone "An object-specific and dose-sparing scatter correction approach for a dedicated cone-beam breast CT system using a parallel-hole collimator", Proc. SPIE 8313, Medical Imaging 2012: Physics of Medical Imaging, 831303 (23 February 2012); https://doi.org/10.1117/12.911093

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available