Fixed anterior gantry CT shielding

摘要

A radiation shield is fixed to scanning equipment at a location that attenuates a moving beam of radiation only while the beam passes over a relatively vulnerable portion, especially anterior portion, of the patient's body. Such an in-plane shield can be selective as to radiation wavelength attenuation. As an example, for scanners that use X-rays, the low energy portion of the spectrum can be selectively blocked while the high energy portion of the spectrum passes through to the patient and detector. When embodied in a CT X-ray scanner, the selective attenuation can be achieved with a thin slice bismuth shield/filter permanently installed on at least the anterior quadrant of the gantry, preferably on a span of approximately about 140 deg. in registry with the circular path of the source.

主权项

1. A medical radiation scanning device for imaging a region of a patient's body, comprising: a gantry defining a space for receiving said region of a patient's body; a source of a scanning beam of radiation movable around said region of a patient's body; a radiation shield fixed in the gantry in stationary relationship to the movable scanning beam at a location that attenuates the movable scanning beam of radiation only while the movable scanning beam of radiation passes over a relatively vulnerable portion of said region of the patient's body while said region of the patient's body is in said space; wherein the medical radiation scanning device is a CT body scanner that uses said scanning beam of radiation having a spectrum of X-radiation energy, and the low energy portion of the X-ray spectrum is preferentially attenuated by the radiation shield while the high energy portion passes through the radiation shield substantially unaffected.