Erfassung von volumetrischen Bilddaten

A gantry (10) includes a large diameter bearing having an outer race (12) and an inner race (16) which surrounds an examination region. An x-ray tube (18) and collimator (52) are mounted to the inner race, as is a flat panel detector (20) and a mechanical mechanism (50) for moving the flat panel detector closer to and further from the examination region. A timing and control circuit (30) controls a motor (22) which indexes the inner race around the examination region, an x-ray power supply (32) which pulses the x-ray tube in a fluoroscopic mode at discrete positions around the examination region, and a read-out circuit (34) which reads out a frame of data after each pulse of the x-ray tube. The read out frames of data are stored in a frame memory (36) and reconstructed by a reconstruction processor (38) into a volumetric image representation for storage in a volume image memory (40). A video processor (42) reformats individual frames from frame memory (36) or selected portions of volume image representation from the volume image memory (40) into appropriate format for display on a video monitor (44). A magnification control (54) coordinates adjustment of the collimator (52) and movement of the flat plate detector toward and away from the examination region.