Dynamic collimation

An imaging systems, comprising:

• a radiation source that emits radiation in a direction towards an examination region;
• a collimator having at least one collimating member that collimates the emitted radiation, producing a radiation beam having a predetermined shape and that traverses the examination region, wherein the collimator dynamically adjusts a geometry and/or location of the radiation beam for one or more view angles in accordance with a geometry and/or location of a region of interest in a portion of an object or subject disposed in the examination region, wherein the region of interest is a sub-region of the portion of the object or subject disposed in the examination region;
• and
• a detector array, located opposite the source and across the examination region, that detects radiation traversing the examination region and generates a signal indicative of the detected radiation.

A method for optimizing dose in an imaging examination, comprising:

• identifying a region of interest of object or subject to scan in a two dimensional projection image of the object or subject;
• collimating emitted radiation so that radiation traversing the examination region substantially only irradiates the region of interest while not irradiating a remainder portion of the object or subject;
• and
• adjusting the collimation as needed so that the radiation continues to substantially only irradiate the region of interest while not irradiating the remainder portion for the imaging examination.