Improved Image Quality in Digital Mammography Using Anti-Scatter Grids

Abstract

Curability and effective management of breast cancer are dependent on its early detection. Early diagnosis strategies focus on providing timely access to breast cancer treatments by reducing barriers and improving access to effective early diagnosis. Mammography is the screening method of choice but suffers from degrading effects of scatter photons obstructing visualization of ductal carcinoma in situ and micro-calcifications in the breast. Quantitative evaluation of scatter suppression by anti-scatter grid using the beam stopper method has been investigated. Breast tissue equivalent phantom, polymethyl methacrylate was evaluated at X-ray mammographic nominal energy ranges. The anti-scatter grid used had aluminium interspace material and carbon fibre covers with varying grid features. Transmitted scatter and primary photon to the detector was analysed and evaluated. A scintillator type detector–model a Dexela 2315 MAM of size 290.8 ×229.8 mm having a resolution of 3072×3888 pixels was used. Transmitted scatter values in the range of 0.123 to 0.243 across the polymethyl methacrylate thickness of 10 mm to 80 mm were observed, whereas transmitted primary values recorded ranged from 0.713 to 0.495. Object, anti-scatter grid and X-ray energy exposure factors influenced the scatter fraction significantly. Improved mammography images showed significant improvements with this scatter reduction method using anti-scatter grid.

Keywords: Digital mammography; Anti-scatter grids; Breast screening; Scatter image artifacts; Beam stopper method;