Patent ID: 7953208
Filing Date: 2011-05-31
Classification: A61B,G21K

Abstract:
1. A method for collimating an x-ray beam comprising the steps of: mounting a diaphragm with a fixed aperture opening therein in a path of x-rays, and movably mounting a slotted plate comprised at least partially of material that is impermeable to x-rays and having a slot therein, to allow said slotted plate to be moved between two end positions relative to said path and relative to said fixed aperture opening to collimate said x-rays to form an x-ray beam; configuring said two end positions and said slotted plate to cause said fixed aperture opening and said slot to overlap to produce substantially no masking of said x-rays when said slotted plate is in a first of said end positions, and to mask all of said x-rays, by said fixed aperture opening and said slot not overlapping, when said slotted plate is in a second of said end positions, with said fixed aperture opening and said slot defining an adjustable aperture for passage of said x-rays as said slotted plate is moved between said two end positions; conducting a scan of a subject with said x-rays to obtain x-ray image data from a predetermined region of the subject; and automatically controlling movement of said slotted plate to automatically adjust said adjustable aperture during said scan to minimize exposure of the subject to said x-rays by substantially confining irradiation of the subject with said x-rays to said region.