[A new method for eliminating scatter components from a digital X-ray image by later processing].

The anti-scatter grid is generally used as a way of eliminating scattered radiation from X-ray photographs. This does not change even if the detector system changes from an analogue system to a digital system such as the flat-panel detector. We developed a new method that uses software to eliminate scatter components from digital X-ray images taken without the use of an anti-scatter grid. With this software, scatter components are eliminated from the X-ray image according to primary-to-scatter ratios, which were calculated on the basis of an imaginary phantom constructed by the pixel value of the X-ray image and on the spectrum of irradiated X-rays. In a trial calculation using a simulation image, it was confirmed that scatter components are eliminated at a high rate that is generally constant on the whole, irrespective of the kind and presence of the inhomogeneous region. When using this technique, the amount of X-ray exposure to a patient can be substantially reduced compared with that of radiography using the anti-scatter grid. Subsequently, the patient dose can be reduced.