title: [X-ray phase imaging using a X-ray tube with a small focal spot -improvement of image quality in mammography-].
abstract: Phase contrast X-ray imaging has been studied intensively using X-rays from synchrotron radiation and micro-focus X-ray tubes. However, these studies have revealed the difficulty of this technique's application to practical medical imaging. We have created a phase contrast imaging technique using a molybdenum X-ray tube with a small focal spot size for mammography. We identified the radiographic conditions in phase contrast magnification mammography with a screen-film system, where edge effect due to phase contrast overcomes geometrical unsharpness caused by the 0.1mm-focal spot of a molybdenum X-ray tube. The edge enhancement due to phase imaging was observed in an image of a plastic tube, and then geometrical configuration of the X-ray tube, the object and the screen-film system was determined for phase imaging of mammography. In order to investigate a potential for medical application of this method, we conducted evaluation of the images of ACR 156 mammography phantom. We obtained higher scores for phase imaging using high speed screen-film systems without any increase of X-ray dose than the score for contact imaging using a standard speed screen-film system.
authors.affiliation: MG Research and Development center, Konica Corporation, Japan. C.Honda@konica.co.jp
authors.forename: Chika
authors.initials: C
authors.lastname: Honda
authors.forename: Hiromu
authors.initials: H
authors.lastname: Ohara
authors.forename: Akira
authors.initials: A
authors.lastname: Ishisaka
authors.forename: Fumio
authors.initials: F
authors.lastname: Shimada
authors.forename: Tokiko
authors.initials: T
authors.lastname: Endo
mesh_terms: D005260:Female; D006801:Humans; D008327:Mammography / Q000295:instrumentation* / Q000379:methods; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods; D011858:Radiographic Magnification / Q000295:instrumentation* / Q000379:methods