Hitachi Medical Corporation

Toshiyuki Irie

Koichi Hirokawa

Osamu Miyazaki

Taiga Goto

Hironori Ueki

Keisuke Yamakawa

Yoshiaki Sugaya

Yasuhiro Fukui

An X-ray CT apparatus is configured capable of properly calculating a radiation dosed amount more approximating to an actually exposed radiation dose that includes scattering rays of an examined object from data measured at the scanning time. A function or table showing a relationship between data obtained on the basis of the measured data of the object detected by an X-ray detector at the scanning time and the radiation dosed amount is stored in advance; and the X-ray CT apparatus calculates the radiation dosed amount of the object in accordance with the data obtained on the function or table showing the relationship between the data obtained on the basis of the measured data of the object stored in advance and the radiation dosed amount.

X-ray CT apparatus

A view image of high time resolution acquired in an imaging process of X-ray CT is displayed. In this display, by subtracting a background image obtained by forward projection calculation of a CT image from the view image, background is removed from the view image, and only a focused site is imaged. A transmission image of the focused site showing high display contrast and not easily influenced by a motion artifact can be thereby obtained. Thereby, in an X-ray CT device for diagnostic imaging, degradation of diagnostic ability due to motion artifacts can be prevented.

X-ray CT device

A tomographic system displays plural tomographic images, a relative distance between the tomographic images, whereby the operator can see the displayed data of the relative distances between tomographic images and the length of the treatment device instantaneously, and can therefore determine the insert position or the treatment device for the subject efficiently.

Tomographic system

An X-ray CT apparatus acquires a scanogram of an object to be examined, generates an ellipse model having an X-ray attenuation coefficient equivalent to that of water and approximated to a tomographic image of the obtained imaged portion from the feature quantity of the projection value profile, determines whether or not the generated elliptic model is adequate as a model of the imaged portion from another feature quantity with respect to the projection value profile, generates a corrected elliptic model according to yet another feature quantity with respect to the projection value profile if the elliptic model is determined to be inadequate, and controls the modulation of the tube current in an X-ray source so that a predetermined target SD value is maintained in any scanning position when a tomographic image is reconstructed according to X-rays transmitted through the object by using the elliptic model or the corrected elliptic model.

An X-ray CT apparatus includes a projection data analysis part that reconstructs a tomographic image at an imaging portion of the object used for analysis from the projection data and produces a control profile by reprojecting the reconstructed tomographic image, and a tube current control part that controls value of current to be fed to the X-ray tube based on the produced control profile.

Growing community of inventors

Tokyo, Japan

Toshiyuki Irie