| 摘要 |
PURPOSE:To offer an X-ray diagnosis device furnished with a preexposure device prior to the main pick-up which enables the least equivalent water thickness of a subject and the thickness of the subject corresponding to ROI to be estimated. CONSTITUTION:In the prepick-up, the least equivalent water thickness lmin, being expressed in a transmission water phantom of a subject, which gives the greatest concentration in a picture, and the equivalent water thickness lx of the subject, which corresponds to ROI are estimated by a thickness fixing means 10E for outputting these to the third operation means 10F. The third operation means 10F sets the most suitable pick-up conditions of tube voltage, a tube current and gain, which are capable of making the S/N ratio of the picture to be maximum and attaining the supreme concentration resolution on the basis of said estimation for outputting it to an X-ray controller 9. In this way, the most suitable conditions of the X-ray tube 1 and an optical system 7 get to be realized. Accordingly, the picture obtained by injecting a contrast medium into the subject 2 for performing the X-ray pick-up under the most suitable condition said above gets to be displayed as an X-ray picture having a high contrast between the picture in the part to be discriminated of an object, for instance, of a blood vessel, wherein the contrast medium is existing, and the picture of the other part, together with good resolution. |
