The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 28, 1997
Filed:
Jun. 21, 1996
Hung Y Wong, Solon, OH (US);
Robert J Vagi, Broadview Hts., OH (US);
Picker International, Inc., Highland Heights, OH (US);
Abstract
A patient is positioned on a patient support (12) and a gantry (16) carrying an x-ray source (10) and a radiation detector assembly (14) are rotated around the subject. The detector assembly includes a video camera (28) which is run in a synchronous mode to generate a first plurality of images at regular temporal intervals T.sub.blanking. Because each image requires a finite time for generation, it is acquired over an interval of arc between a starting angular orientation (A.sub.S .degree., B.sub.S .degree.) and a terminal angular orientation (A.sub.T .degree., B.sub.T .degree.). A position encoder (40) monitors the terminal positions of each of the first series of images. The patient is then injected with a radiographic dye and the gantry is rotated in a reverse direction. A comparator compares the stored terminal angular positions of each forward direction image and the current angular position of the gantry. A trigger circuit (54) triggers an asynchronous mode x-ray exposure controller (50) such that a video image is commenced at each terminal angular orientation. Images generated over substantially the same arc segment are subtracted (66) to form a difference image for storage in a difference image memory (68) and display on a monitor (72).