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:
Jan. 22, 2002
Filed:
Feb. 28, 1997
Ming Xu, San Ramon, CA (US);
Zheng Chen, Pleasant Hill, CA (US);
Siemens Medical Systems, Inc., Iselin, NJ (US);
Abstract
An improved acquisition scheme for a medical imaging and treatment system According to one aspect of the invention, adaptive radiation detection, for determining when therapeutic or diagnostic radiation is being applied, is provided. The imaging device acquires several test images during a preacquisition delay. The maximum intensity level from these test images is defined as the upper limit of a camera 's response in the darkness. The standard deviation of the intensity distribution is also computed. The image intensity level of the subsequent test images are compared to a radiation detection threshold which is determined to be the upper limit of the camera's dark signal, plus twice the standard deviation of pixel intensity distribution of the dark test images. If the intensities of a statistically significant number of pixels exceeds the threshold, the radiation is considered to be on. According to another aspect of the invention, a single look-up table is used for both the test images and the actual acquisition images. The single look-up table is downloaded upon detection of power to a linear accelerator According to still another aspect of the present invention calibration of a lower bound of a signal of interest occurs using a histogram based algorithm, so that only the histogram needs to be transferred from the imaging board to the host computer. Furthermore, the present invention is capable of automatically calculating the upper bound of a signal of interest. In addition, the present invention is configured for continuous image integration such that each acquisition cycle is repeated until the linear accelerator is turned off. Thus, the final image is the integration of images from each acquisition cycle.