Method and apparatus for adjusting technical exposure factors during radiographic acquisition

摘要

A method and apparatus for acquiring a radiographic image of a patient includes using an X-ray source and at least a X-ray detector supported in opposed positions, the area under investigation being positioned between the X-ray source and detector in the propagation bundle of the radiation emitted by the X-ray source, the X-ray source and detector being movable along a pre-set trajectory due to at least two movements. The X-ray dose administered to a patient can be adjusted automatically, dispensing the minimum dose necessary to achieve a radiographic image of good quality. The method and apparatus provide for performing a scout acquisition, preceding the acquisition of a real panoramic image, in a particularly efficient way. During the scout acquisition, data are collected for adjusting the X-ray dose for the following radiographic image acquisition.

主权项

1. A method of patient specific, real time automatic adjustment of a technical exposure factor selected from the group consisting of X-ray tube power (kV), X-ray tube current (mA), exposure duration (sec), and film speed to acquire a radiographic image, the method comprising the following steps:
(a) performing a scout acquisition of an image of a specific anatomical area of a patient using pre-defined parameters; (b) extracting a region of interest (ROI) from the scout acquisition; (c) developing a grey level histogram of image pixels from the ROI; (d) segmenting the grey level histogram into a plurality of sectors; (e) assigning a coefficient to each sector; (f) assigning a weight to each coefficient; (g) computing an exposure parameter according to the weight assigned to each sector; and (h) performing an exposure of a real acquisition using the exposure parameters.