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

A rotating laminar emission camera comprising:

• a detector having a side which detects radiation facing an object being studied, said detector rotating about an axis perpendicular to the side of the detector facing the object;
• and,
• a collimator constructed of a radiation attenuative material arranged on the side of the detector facing the object, said collimator including a plurality of spaced apart slats, each of said slats being tilted at an angle greater than zero with respect to the axis, and all of said slats tilting away from the axis toward a same side thereof;
• wherein the slats are thin rectangular members with two rounded corners at opposing longitudinal ends of each slat, said two rounded corners being opposite an edge of the slats proximal to the side of the detector facing the object.

A nuclear medical imaging apparatus comprising:

• a receiving region wherein an object being imaged is received;
• a radiation detector having a side which faces the receiving region, said detector including;
• a collimator fabricated from radiation attenuative material arranged on the detector between the detector and the receiving region, said collimator including a plurality of spaced apart slats which are tilted at an angle greater than zero with respect to a central axis perpendicular to the side of the detector which faces the receiving region;
• a drive which imparts about the central axis relative rotation between the detector and the object being imaged;
• and,
• a data processor which subtracts data obtain from the radiation detector at a first angular orientation about the central axis from data obtained from the radiation detector at a second angular orientation about the central axis, said first and second angular orientations being displaced from one another by 180 degrees.

A method of nuclear medical imaging comprising:

• (a) exposing a side of a radiation detector to an object being imaged, wherein a direction the detector is facing is defined by an axis perpendicular to the side of the detector;
• (b) varying about the axis a relative rotational orientation between the object and the detector;
• (c) obtaining a first data set based on radiation detected by the detector at a first relative rotational orientation between the object and the detector;
• (d) obtaining a second data set based on radiation detected by the detector at a second relative rotational orientation between the object and the detector, said second relative rotational orientation being displaced from the first relative rotational orientation;
• and,
• (e) subtracting the second data set from the first data set to determine a difference between the first and second data sets.

A method of nuclear medical imaging comprising:

• (a) exposing a side of a radiation detector to an object being imaged, wherein a direction the detector is facing is defined by an axis perpendicular to the side of the detector;
• (b) varying about the axis a relative rotational orientation between the object and the detector;
• (c) collimating radiation received by the detector such that radiation received by the detector is substantially limited along one direction to a reception trajectory having an angle greater than zero with respect to the axis;
• (d) obtaining a first data set based on radiation detected by the detector at a first relative rotational orientation between the object and the detector;
• (e) obtaining a second data set based on radiation detected by the detector at a second relative rotational orientation between the object and the detector, said first and second relative rotational orientations being displayed displaced from one another by 180 degrees;
• and,
• (f) subtracting one of the first and second data sets from the other to determine a difference between the first and second data sets.