Abstract
The effect of pixel size on shape determination in screening digital mammography systems was studied using a shape identification task as the measured outcome. Ten microcalcifications on screen-films were digitised to a range of pixel sizes (2.5-200 μm) and extracted from computed radiography (CR) images (50 μm) acquired under equivalent imaging conditions. Fifteen observers attempted to identify the shape of each microcalcification at each pixel size. The results were collated to provide a fraction of correct responses vs. pixel size curve for each microcalcification. Averaging over all shapes, pixel values > 100 μm lead to a significant decrease in shape determination ability (p < 0.01) for digitised screen-film. For CR images, half the shapes were not properly identified. Hence, although 20-100 μm was sufficient for microcalcification shape determination for digitised screen-film images, 50 μm was only borderline sufficient for the CR digital images
Original language | English |
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Pages (from-to) | 415-423 |
Journal | Radiation Protection Dosimetry |
Volume | 114 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - 2005 |
Event | Second Malmo Conference on Medical X-Ray Imaging - Malmo, Sweden Duration: 2004 Apr 25 → … |
Subject classification (UKÄ)
- Radiology, Nuclear Medicine and Medical Imaging
Free keywords
- computed radiography
- 2.5 to 200 micron
- digitised screen-film
- shape identification
- digital mammography
- microcalcification
- shape determination
- threshold pixel size