Routine quality control tests for film-screen mammographic systems with automatic exposure control

Area of Science:

• Radiology
• Medical Imaging
• Quality Control

Background:

• Mammogram quality is crucial for patient dose and monitoring breast changes over time.
• Consistent contrast and density are essential for accurate mammographic interpretation.
• Existing quality control methods may not adequately address generator and phototiming system consistency.

Purpose of the Study:

• To develop and evaluate a phantom and test technique for monitoring mammographic contrast and density.
• To assess the consistency of mammographic generators and phototiming systems.
• To correlate phantom-derived quality control data with image quality and equipment performance.

Main Methods:

• A specialized phantom with an acrylic block and aluminum step wedge for low kVp mammography was developed.
• Optical densities of the phantom were measured to assess contrast and density constancy.
• The technique minimized variations from film processing and handling.
• Data were collected from two institutions.

Main Results:

• The developed technique effectively monitored mammographic contrast and density consistency.
• Fluctuations due to processing were minimized, allowing detection of generator and phototimer variations.
• Data correlated with processor function, indicating the phantom's utility in quality control.
• Changes in density and contrast values were linked to phototimer malfunction and reduced image quality.

Conclusions:

• The phantom and test technique provide a reliable method for quality control of mammographic contrast and density.
• This approach enhances the ability to detect equipment-related issues affecting image quality.
• Consistent mammography quality control is vital for accurate patient monitoring and effective breast cancer screening.