Pre-object filter for shaping profile of radiation attentuation in fan-angle direction

A computed tomography (CT) system, comprising:

• a radiation source;
• a detector array;
• a rotating gantry configured to rotate the radiation source and the detector array about an object under examination;
• and
• a pre-object filter positioned between the radiation source and the object and configured to shape a profile of radiation attenuation as a function of a profile of the object, wherein:
• the pre-object filter comprises a core extending between a first side and a second side,
• a channel is defined in the core extending in a direction substantially parallel to an axis of rotation of the rotating gantry, and
• the channel has a first width in a first position and a second width in a second position, wherein the second width is larger than the first width.

A method for imaging a patient, comprising:

• acquiring a profile of the patient, the profile describing one or more features of the patient;
• performing an imaging scan on the patient;
• and
• shaping, as a function of the profile of the patient, a profile of radiation attenuation in a fan-angle direction to affect an amount of radiation attenuated in the fan-angle direction, wherein the shaping comprises:
• rotating a pre-object filter about a filter axis, wherein the pre-object filter is configured to shape the profile of radiation attenuation, wherein:
• the pre-object filter comprises a core extending between a first side and a second side,
• a channel is defined in the core extending in a direction substantially parallel to an axis of rotation of the rotating gantry, and
• the channel has a first width in a first position and a second width in a second position, wherein the second width is larger than the first width.