Correction for depth-dependent sensitivity in rotating slat-collimated gamma camera

A nuclear medical imaging apparatus comprising:

• a receiving region wherein an object being imaged is received;
• a radiation detector having an array of detector elements on a side which faces the receiving region, said side having an axis which is substantially normal thereto;
• a collimator fabricated from radiation attenuative material arranged on the detector between the detector and the receiving region, said collimator including a plurality of slats that have a spacing from one another such that in the direction of the spacing a plurality of detector elements are positioned between adjacent pairs of slats;
• and,
• a drive which imparts about the axis relative rotation between the collimator and the object being imaged.

A method of nuclear medical imaging comprising:

• (a) exposing a detector including an array of radiation detecting elements to an object being imaged;
• (b) restricting radiation acceptance for the detector such that different fields of view are established for elements in the array;
• (c) obtaining a first data set based on radiation detected via a first set of elements in the array;
• (d) obtaining a second data set based on radiation detected via a second set of elements in the array;
• and,
• (e) subtracting the second data set from the first data set to determine a difference between the first and second data sets.

A nuclear medical imaging apparatus comprising:

• means for exposing a detector including an array of radiation detecting elements to an object being imaged;
• means for restricting radiation acceptance for the detector such that different fields of view are established for elements in the array;
• means for obtaining a first data set based on radiation detected via a first set of elements in the array;
• means for obtaining a second data set based on radiation detected via a second set of elements in the array;
• and,
• means for subtracting the second data set from the first data set to determine a difference between the first and second data sets.