Multimodality imaging system

A method of multimodal imaging of an object, the method comprising:

• performing spatio-temporal detection of transmission CT data of a fan X-ray beam;
• performing, simultaneously with the spatio-temporal detection of transmission CT data, spatio-temporal detection of emission nuclear imaging data emitted from the object with a propagation direction across the propagation direction of the fan X-ray beam;
• identifying at least two zones in the object based on the transmission CT data;
• reconstructing an image object from the emission nuclear imaging data under the constraint that respective portions of detected nuclear events are associated with selected zones:
• and
• outputting data representative of the image object.

A multimodality imaging system comprising:

• a gantry with a stationary unit and a rotating unit rotatable around a rotation axis, the gantry having a wall forming an opening extending along the rotation axis, wherein
• a CT source coupled to the rotating unit, the CT source being configured to emit a fan beam through the opening,
• a CT detector coupled to the rotating unit, the CT detector being mounted opposite the CT source and configured to detect the fan beam, the CT source and the CT detector defining a CT field-of-view, and
• a nuclear imaging detector coupled to the rotating unit, the nuclear imaging detector being configured to detect nuclear radiation emitted from within the opening in a direction differing from a propagation direction of the fan beam, the nuclear imaging detector defining a nuclear field-of-view,
• wherein at least one of the CT field-of-view and nuclear field-of-view are tilted with respect to a plane orthogonal to the axis of rotation.