2021 年 7 巻 p. 28-35
Chest X-ray (CXR) is the most commonly used diagnostic examination in lung cancer screening. The temporal subtraction (TS) processing of CXRs using computer-aided diagnosis (CAD) software is a technique in which a previous CXR is used to enhance evaluation of changes in an intervening time. However, if the superpositioning of the two images is not accurate, excessive misregistration artifacts will make it diffi cult for radiologists to differentiate between true changes and simple artifacts. In this study, we aimed to use bone suppression (BS) processing as a method to reduce artifacts when detecting a lesion became diffi cult due to the occurrence of artifacts between two images. The contrast-to-noise ratios (CNRs) of TS processing images with and without BS processing were calculated and compared based on several types of positions including anterior inclination, lateral inclination, right anterior oblique (RAO), and left anterior oblique (LAO). Our results showed that CNRs were signifi cantly improved with BS processing.
