2013 Volume 5 Issue 4 Pages 228-240
Breast X-ray screening (mammography) was introduced in 2000 to detect breast cancer at an early stage. Since then, the number of examinees has increased steadily. The X-ray dose must be optimized to obtain high-quality images that ensure diagnosis reliability without compromising safety. Mammography utilizes low-energy X-rays with a special energy spectrum for breast cancer screening. This X-ray energy spectrum is significantly different from the reference X-ray spectrum used to calibrate dosimeters. Members of industry and academia were concerned about the reliability of dose evaluation for mammography quality control. Thus, the National Metrology Institute of Japan/National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has established an X-ray dose standard based on the X-ray energy spectrum for mammography and has disseminated this standard to industry. NMIJ has succeeded in rapidly establishing this standard by making the utmost use of existing research equipment and technology, and by utilizing the standard in the existing mammography quality control system. Moreover, it created a research and development (R&D) scenario beforehand considering both domestic and international situations regarding mammography dosimetry that has enabled rapid and extensive dissemination of the standard with international consistency.
