THREE-DIMENSIONAL DOSIMETRY OF MAMMOGRAPHY USING A BLOCK CUBE BREAST PHANTOM AND RADIOCHROMIC FILM

This study developed a phantom with a shape similar to that of the breast and use GAFCHROMIC films that can be placed inside the phantom to measure the detailed breast dose distribution in mammography. GAFCHROMIC EBT3 was placed on the block cube breast phantom and irradiated with a mammography device to measure the absorbed dose distribution inside the phantom in the horizontal and depth directions. The dose distribution in the horizontal plane was the highest in the centre on the chest wall side, and it decreased in a fan shape. Along the depth of the phantom, the doses absorbed across the entire cross-section were 16.15 mGy at the surface and 7.51, 3.25 and 1.68 mGy at depths of 10, 20 and 30 mm, respectively. Compared with the mean glandular dose, the proposed method can measure breast dose distributions in greater detail and is applicable to various breast shapes.