Initial evaluation of a modified dual-energy window scatter correction method for CZT-based gamma cameras for breast SPECT

Steve D. Mann; Martin P. Tornai

doi:10.1117/12.2082195

20 March 2015 Initial evaluation of a modified dual-energy window scatter correction method for CZT-based gamma cameras for breast SPECT

Steve D. Mann, Martin P. Tornai

Author Affiliations +

Proceedings Volume 9413, Medical Imaging 2015: Image Processing; 94132X (2015) https://doi.org/10.1117/12.2082195
Event: SPIE Medical Imaging, 2015, Orlando, Florida, United States

Abstract

Solid state Cadmium Zinc Telluride (CZT) gamma cameras for SPECT imaging offer significantly improved energy resolution compared to traditional scintillation detectors. However, the photopeak resolution is often asymmetric due to incomplete charge collection within the detector, resulting in many photopeak events incorrectly sorted into lower energy bins (“tailing”). These misplaced events contaminate the true scatter signal, which may negatively impact scatter correction methods that rely on estimates of scatter from the spectra. Additionally, because CZT detectors are organized into arrays, each individual detector element may exhibit different degrees of tailing. Here, we present a modified dualenergy window scatter correction method for emission detection and imaging that attempts to account for positiondependent effects of incomplete charge collection in the CZT gamma camera of our dedicated breast SPECT-CT system. Point source measurements and geometric phantoms were used to estimate the impact of tailing on the scatter signal and extract a better estimate of the ratio of scatter within two energy windows. To evaluate the method, cylindrical phantoms with and without a separate fillable chamber were scanned to determine the impact on quantification in hot, cold, and uniform background regions. Projections were reconstructed using OSEM, and the results for the traditional and modified scatter correction methods were compared. Results show that while modest reduced quantification accuracy was observed in hot and cold regions of the multi-chamber phantoms, the modified scatter correction method yields up to 8% improved quantification accuracy with 4% less added noise than the traditional DEW method within uniform background regions.

Citation Download Citation

Steve D. Mann and Martin P. Tornai "Initial evaluation of a modified dual-energy window scatter correction method for CZT-based gamma cameras for breast SPECT", Proc. SPIE 9413, Medical Imaging 2015: Image Processing, 94132X (20 March 2015); https://doi.org/10.1117/12.2082195

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

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
10 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Directed energy weapons

Sensors

Single photon emission computed tomography

Cameras

Breast

Calibration

Cadmium

Show All Keywords

Keywords/Phrases

Search In:

Publication Years