An Innovative Concept of a 3D-Coded Aperture Imaging System Proposed for Early Breast Cancer Detection

Area of Science:

• Nuclear Medicine
• Medical Imaging
• Biomedical Engineering

Background:

• Coded Aperture (CA) imaging is emerging in nuclear medicine, but commercial SPECT cameras for cancer detection are lacking.
• Existing CA methods excel in planar and thin 3D imaging, yet thick 3D reconstruction for small lesions remains a challenge.

Purpose of the Study:

• To present a novel Coded Aperture (CA) SPECT imaging system for improved 3D breast phantom reconstruction.
• To evaluate the system's efficacy in detecting small lesions within a 3D breast phantom.

Main Methods:

• Utilized a mosaic modified uniformly redundant array (MURA) mask/antimask Coded Aperture (CA).
• Employed the maximum-likelihood expectation-maximization (MLEM) iterative algorithm for slice-by-slice 3D reconstruction.
• Stacked reconstructed slices to create a complete 3D breast phantom image from single-projection data.

Main Results:

• Successfully reconstructed a 3D anthropomorphic breast phantom with lesions as small as 3 mm.
• Demonstrated effective background noise suppression by leveraging the mask/antimask difference.
• Quantified lesion quality using contrast-to-background ratio (CBR), peak signal-to-noise ratio (PSNR), and mean square error (MSE).

Conclusions:

• The proposed CA SPECT imaging system shows promise for reconstructing 3D breast phantoms from single-projection data.
• This technology has the potential to enhance small lesion detection in nuclear medicine applications.
• Further development could lead to advanced SPECT imaging cameras for improved cancer diagnostics.