Direct Detection of Microcalcification Pairs in Simulated Digital Mammograms

Abstract

Using the MCMIS (Monte Carlo for Mammography Image Simulation) code, several possible scenarios of microcalcification images were simulated for the Fischer Senoscan™ digital mammography system, which has been approved for clinical use by the F.D.A. The cases simulated included detectors that have 100 μm x 100 μm, 50 μm x 50 μm, and 25 μm x 25 μm pixels in order to determine how much improvement can be obtained through decreased pixel size in the detection of microcalcification clusters in mammograms. Breast thickness was also varied for each modality from 4 to 7 cm in order to determine the effect that reduced breast compression will have on image quality under ideal conditions. The breast phantom used for each simulation included a region of microcalcification pairs of varying size and pair spacing. This microcalcification cluster phantom was designed such that simulated images would indicate the minimum required size and spacing for microcalcification clusters to become distinctly discernable in each of the modalities under scrutiny. Both qualitative and quantitative analyses were performed for each simulated image produced. A decrease in detector pixel size did not show the expected result of significant improvement in cluster detection ability, even under ideal conditions. However, for the range of breast thickness studied, results indicate that decreasing the amount of compression during a mammogram did not significantly affect the image quality in terms of image resolution or contrast for all detector modalities tested. These results suggest that new detector modalities incorporating smaller detector pixel sizes may not show significant improvement over current modalities. However, they also suggest that doctors may be able to make the mammogram process less painful for the patient while maintaining image quality.

Description

Keywords

resolution, contrast, microcalcifications, mammography

Citation

Degree

MS

Discipline

Nuclear Engineering

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