Related Experiment Video
Updated: May 16, 2026
05:28
Clinical Imaging of Microwave Mammography
Published on: November 14, 2025
Implementation and evaluation of an expectation maximization reconstruction algorithm for gamma emission breast
Zongyi Gong1, Kelly Klanian, Tushita Patel
1Department of Physics, University of Virginia, Charlottesville, VA, USA.
Medical Physics
|December 13, 2012
Summary
This study introduces a new reconstruction algorithm for gamma emission breast tomosynthesis (GEBT), improving lesion detection and image quality. The developed method enhances contrast and signal-to-noise ratio compared to traditional planar imaging.
Area of Science:
- Medical Imaging
- Nuclear Medicine
- Image Reconstruction
Background:
- Developing a dual modality tomosynthesis breast scanner combining X-ray transmission and gamma emission.
- Acquiring projection data with incomplete and asymmetrical angular sampling (<180°) from one side of the breast.
Purpose of the Study:
- Implement and evaluate a maximum likelihood expectation maximization (MLEM) reconstruction algorithm for gamma emission breast tomosynthesis (GEBT).
- Utilize prior information from X-ray tomosynthesis for compensation and correction.
Main Methods:
- Employ Monte Carlo simulations and phantom experiments to test the MLEM algorithm for GEBT.
- Incorporate prior information, attenuation correction (AC), and resolution recovery (RR) into the algorithm.
- Evaluate image quality metrics including spatial resolution, artifacts, contrast, and SNR across various angular ranges (45°, 90°, 135°).
Main Results:
- Achieved near-isotropic, spatially uniform 3D resolution of approximately 4.3 mm FWHM with a 135° acquisition.
- Demonstrated significant improvements in lesion contrast (2.6-8.8x) and SNR (2.3-5.6x) compared to planar scintigraphy.
- Showed that AC and RR substantially reduce artifacts and depth-dependent degradation of lesion signal.
Conclusions:
- A promising EM-based reconstruction scheme for GEBT has been demonstrated.
- GEBT offers superior, position-independent lesion contrast, SNR, and spatial resolution compared to planar breast scintigraphy.
- GEBT enables more accurate quantification of lesion-to-background activity concentration ratios.
Related Concept Videos
01:27Imaging Studies III: Computed Tomography
DefinitionComputed Tomography (CT) of the genitourinary (GU) tract is a non-invasive imaging modality that utilizes X-rays and computer processing to generate detailed cross-sectional images of the urinary system, encompassing the kidneys, ureters, bladder, and adjacent structures such as the adrenal glands.PurposeCT scans of the GU tract serve several diagnostic and therapeutic purposes, including:Diagnosis of Urinary Tract Diseases: Detects kidney stones, tumors, cysts, and congenital...
01:10Computed Tomography
Tomography refers to imaging by sections. Computed tomography (CT) is a non-invasive imaging technique that uses computers to analyze several cross-sectional X-rays to reveal minute details about structures in the body.
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...