| 摘要 |
The disclosure is directed to a method and apparatus for generating a processed image of a cross-section through a body. Fluoroscopic tomography is achieved wherein a series of video frames of a cross-section of a body can be viewed in real time. In this manner, for example, one can monitor the progress of a bolus of contrast material moving through a blood vessel in the cross-section being viewed. In a form of the disclosure, a recorded series of frames of a principal plane of a body being imaged can be processed to obtain a corresponding series of frames that represent a plane of interest that is spaced from the principal plane, thereby avoiding the necessity of re-exposure for each new plane to be viewed. In accordance with the disclosed method, a body is disposed between a combination of a source of radiation and an associated detector, such that a beam of radiation from the source impinges angularly on the body and passes through to the detector. Relative rotational motion is effected between the beam and the body, such that a principal plane of interest in the body remains substantially in focus during the relative rotational motion. A series of frames of electronic video signals are derived from the detector, at different rotational positions, the frames representing images of the radiation transmission characteristics of the body at a series of successive times. The series of frames are temporally filtered and then displayed. In a preferred embodiment, the temporal filtering step comprises filtering the series of frames of video signals with a filter function having a temporal frequency response that corresponds substantially the temporal frequency of the movement of a bolus of contrast material through the region being imaged.
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