Threshold pixel size for shape determination of microcalcifications in digital mammography: a pilot study.

• 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 microm) and extracted from computed radiography (CR) images (50 microm) 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 microm 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 microm was sufficient for microcalcification shape determination for digitised screen-film images, 50 microm was only borderline sufficient for the CR digital images.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Radiologi och bildbehandling (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Radiology, Nuclear Medicine and Medical Imaging (hsv//eng)

Nyckelord

Breast Diseases

diagnosis

Calcinosis

diagnosis

Female

Humans

Mammography

instrumentation

methods

Pilot Projects

Radiographic Image Interpretation

Computer-Assisted

methods

Radiographic Magnification

methods

computed radiography

2.5 to 200 micron

digitised screen-film

shape identification

digital mammography

microcalcification

shape determination

threshold pixel size

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)