Afterglow detection and count rate generation in a nuclear imaging system
AssigneeSiemens Medical Solutions USA, Inc.
InventorRoger E. Arseneau
Life of this patent
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Abstract
The afterglow and count rate/dead time of a nuclear imaging detector are calculated for use in correcting event detection and energy integration circuits. Energy value signals and event triggering signals are respectively integrated as a function of the decay setting of the detector, until they reach stable values, which are respectively used as afterglow and count rate/dead time signals used by a data processor of the detector.
Claims20
A method of determining an afterglow value of a gamma interaction in a nuclear imaging detector, comprising the steps of:
- (a) obtaining a sample of an energy signal from said nuclear imaging detector;
- (b) integrating said sample over a predetermined amount of time to obtain an integrated sample;
- (c) adding said integrated sample to a predetermined portion of a prior stored sample value to obtain a current stored sample value;
- (d) repeating steps (a)-(d) until said current stored sample value has reached a stable value;
- and
- outputting said stable value as an afterglow signal.
A method of determining a count rate value of a gamma interaction in a nuclear imaging detector, comprising the steps of:
- (a) obtaining an event start signal from said nuclear imaging detector;
- (b) integrating said event start signal over a predetermined amount of time to obtain an integrated event start signal;
- (c) adding said integrated event start signal to a predetermined portion of a prior stored event start signal value to obtain a current stored event start signal value;
- (d) repeating steps (a)-(d) until said current stored event start signal value has reached a stable value;
- and
- outputting said stable value as a count rate signal.
A computer program product comprising a computer-readable storage medium containing computer-executable instructions stored thereon, including computer-executable instructions for:
- (a) obtaining a sample of an energy signal from a nuclear imaging detector;
- (b) integrating said sample over a predetermined amount of time to obtain an integrated sample;
- (c) adding said integrated sample to a predetermined portion of a prior stored sample value to obtain a current stored sample value;
- (d) repeating steps (a)-(d) until said current stored sample value has reached a stable value;
- and
- outputting said stable value as an afterglow signal.
A computer program product comprising a computer-readable storage medium containing computer-executable instructions stored thereon, including computer-executable instructions for:
- (a) obtaining an event start signal from a nuclear imaging detector;
- (b) integrating said event start signal over a predetermined amount of time to obtain an integrated event start signal;
- (c) adding said integrated event start signal to a predetermined portion of a prior stored event start signal value to obtain a current stored event start signal value;
- (d) repeating steps (a)-(d) until said current stored event start signal value has reached a stable value;
- and
- outputting said stable value as a count rate signal.
A circuit for determining an afterglow value of a gamma interaction in a nuclear imaging detector, comprising:
- means for obtaining a sample of an energy signal from said nuclear imaging detector;
- means for integrating said sample over a predetermined amount of time to obtain an integrated sample;
- means for adding said integrated sample to a predetermined portion of a prior stored sample value to obtain a current stored sample value;
- and
- means for outputting said stable value as an afterglow signal when said current stored sample value has reached a stable value.
A circuit for determining a count rate value of a gamma interaction in a nuclear imaging detector, comprising:
- means for obtaining an event start signal from said nuclear imaging detector;
- means for integrating said event start signal over a predetermined amount of time to obtain an integrated event start signal;
- means for adding said integrated event start signal to a predetermined portion of a prior stored event start signal value to obtain a current stored event start signal value;
- and
- means for outputting said stable value as a count rate signal when said current stored event start signal value has reached a stable value.
Dependencies are inferred from the claim text.