OBJECTIVE: To investigate the effect of exposure factors used in digital screening mammography on image quality of different breast compositions. MATERIAL AND METHODS: A digital mammography unit, with tungsten (W) as target, rhodium (Rh) and silver (Ag) as filters, and amorphous selenium detectors, was used to image Computerized Imaging Reference Systems (CIRS) Model 12A phantoms of thickness 4, 5, and 6 cm. Images of each phantom were obtained using target-filter combinations of W/Rh and W/Ag, at 28, 30, and 32 kVp. Images were evaluated by 5 senior technologists with experience in mammography. Image scores were assigned, for each type of feature present in the phantom. Statistical analysis was performed using nonparametric tests to compare sets of image scores at p = 0.05. RESULTS: A small but statistically significant improvement was detected in the visibility of microcalcifications (8.8 ± 0.2; p = 0.031) for the W/Rh combination but this did not show any differences in the visibility of masses or fibers. The entrance skin dose (ESD) and mean glandular dose (MGD) were lower for the W/Ag (ESD = 1.30-3.70; MGD = 0.44-0.93 mGy) combination compared to W/Rh (ESD = 1.66-5.40; MGD = 0.52-1.12 mGy). The Mann-Whitney test revealed that 30-kV exposure with the W/Rh combination showed a significantly better visibility of specks in the 30/70 phantom compared to other exposures. CONCLUSION: The use of an Rh filter showed a better image quality for all phantoms. 28 and 30 kVp with the W/Rh combination provided a slightly better image quality, and the MGD is less than 1.2 mGy.
OBJECTIVE: To investigate the effect of exposure factors used in digital screening mammography on image quality of different breast compositions. MATERIAL AND METHODS: A digital mammography unit, with tungsten (W) as target, rhodium (Rh) and silver (Ag) as filters, and amorphous selenium detectors, was used to image Computerized Imaging Reference Systems (CIRS) Model 12A phantoms of thickness 4, 5, and 6 cm. Images of each phantom were obtained using target-filter combinations of W/Rh and W/Ag, at 28, 30, and 32 kVp. Images were evaluated by 5 senior technologists with experience in mammography. Image scores were assigned, for each type of feature present in the phantom. Statistical analysis was performed using nonparametric tests to compare sets of image scores at p = 0.05. RESULTS: A small but statistically significant improvement was detected in the visibility of microcalcifications (8.8 ± 0.2; p = 0.031) for the W/Rh combination but this did not show any differences in the visibility of masses or fibers. The entrance skin dose (ESD) and mean glandular dose (MGD) were lower for the W/Ag (ESD = 1.30-3.70; MGD = 0.44-0.93 mGy) combination compared to W/Rh (ESD = 1.66-5.40; MGD = 0.52-1.12 mGy). The Mann-Whitney test revealed that 30-kV exposure with the W/Rh combination showed a significantly better visibility of specks in the 30/70 phantom compared to other exposures. CONCLUSION: The use of an Rh filter showed a better image quality for all phantoms. 28 and 30 kVp with the W/Rh combination provided a slightly better image quality, and the MGD is less than 1.2 mGy.
Authors: Kalpana M Kanal; Elizabeth Krupinski; Eric A Berns; William R Geiser; Andrew Karellas; Martha B Mainiero; Melissa C Martin; Samir B Patel; Daniel L Rubin; Jon D Shepard; Eliot L Siegel; Judith A Wolfman; Tariq A Mian; Mary C Mahoney Journal: J Digit Imaging Date: 2013-02 Impact factor: 4.056
Authors: Lucy M Warren; Alistair Mackenzie; Julie Cooke; Rosalind M Given-Wilson; Matthew G Wallis; Dev P Chakraborty; David R Dance; Hilde Bosmans; Kenneth C Young Journal: Med Phys Date: 2012-06 Impact factor: 4.071
Authors: Hanaa Abdulla Alkhawari; Akram Mahmoud Asbeutah; Abdullah Abdulaziz Almajran; Latifa Abdullah AlKandari Journal: Ann Saudi Med Date: 2021-10-07 Impact factor: 1.526