Abstract: This disclosure relates generally to CT x-ray imaging systems and methods, and particularly to an inverse geometry with tetrahedron beams. Specifically, a dose efficient and controllable inverse geometry tetrahedron beam CT imaging is disclosed. The disclosed CT geometry includes a linear array of x-ray sources perpendicular to a rotation axis of the CT system and rotates together with a linear detector array extended parallel to the rotation axis. The x-ray emission from each of the sources is collimated into a fan-shaped beams projected to the linear detector array. The intensity of each beam is dynamically adjusted and controlled during the rotation of the source array and the detector array. Such a configuration provides control of x-ray intensity over a selected region of interest in a target object during the rotation even if the region of interest is off from the rotation axis, with efficient dose control.

Abstract: A small animal imaging and radiotherapy (RT) irradiator device uses a circular array x-ray source to scan an anatomy of an animal, delivers conventional and ultra-high dose rate of radiation to the treatment target. The multipixel x-ray source includes a ring of focal spots capable of irradiating x-ray beams from around fifty beam angles. The x-ray beams are collimated with a collimator designed in treatment planning.