US 5,608,221 A · Multi-head nuclear medicine camera for dual SPECT and PET imaging with monuniform attenuation correction

Abstract

A dual head nuclear camera system automatically switchable (and optimized) to perform either SPECT imaging or PET imaging that utilizes attenuation correction for nonuniform attenuation in SPECT or PET modes. The dual head detectors contain switchable triggering circuitry so that coincidence detection for PET imaging and non-coincidence detection for SPECT imaging is available. The system uses a variable integration technique with programmable integration interval; variable sized clusters for centroiding, use of dual integrators per PMT channel, the event detection and acquisition circuitry of the camera system is switchable for PET and SPECT imaging. In such a switchable SPECT/Pet dual head camera system, a mechanism and method is shown to perform transmission and emission scanning sessions with two line sources and two detectors wherein two sliding transmission detection windows are employed to differentiate between transmission and emission photons. Transmission and emission data can be collected simultaneously. This system provides that the dual transmission detection windows are each associated with a particular line source and move in synchronization. Further, the two line sources and the two detector windows all move in synchronization in the direction of the long axis of the object being scanned. In this configuration, the system can effectively reduce the amount of cross-talk detected by a detector.

Claims36

Dependent claims

A switchable SPECT/PET nuclear camera system comprising:

a first detector and a second detector for responding to scintillation events;
circuitry for detecting and recording said events, said circuitry switchable to a first mode of imaging for detection and recordation of PET events and said circuitry switchable to a second mode of imaging for detection and recordation of SPECT events, said circuitry coupled to said first detector and to said second detector, said circuitry including a switchable trigger detection unit that is automatically switchable between coincidence detection when said first mode of imaging is selected and non-coincidence detection when said second mode of imaging is selected, wherein said switchable trigger detection unit is coupled to supply a first valid event trigger signal to said first detector causing said first detector to integrate a scintillation event and coupled to supply a second valid event trigger signal to said second detector causing said second detector to integrate a scintillation event;
transmission radiation sources for scanning across fields of view of said first detector and said second detector with transmission radiation, wherein said circuitry detects and records transmission information while said transmission radiation sources are scanning;
a computer system for generating a PET reconstruction based on said PET events which are corrected by said transmission information;
and
wherein said computer system is also for generating a SPECT reconstruction based on said SPECT events which are corrected by said transmission information.

3 more elements

A switchable SPECT/PET mode nuclear camera system comprising:

a first detector and a second detector for responding to scintillation events;
circuitry for detecting and storing said events, said circuitry switchable to a first mode of imaging for detection and recordation of PET events detected by said first detector and said second detector and said circuitry switchable to a second mode of imaging for detection and recordation of SPECT events detected by said first detector and said second detector, said circuitry coupled to said first detector and said second detector;
a gantry mechanism for configuring said first detector and second detector at 90 degree configuration during said second mode of operation, said gantry mechanism for configuring said first detector and said second detector at 180 degree configuration during said first mode of operation;
and
a computer system coupled to said circuitry and for generating a PET reconstruction based on said PET events;
and
wherein said computer system is also for generating a SPECT reconstruction based on said SPECT events.

4 more elements

In a dual SPECT/PET mode of operation nuclear camera system including at least a first detector and a second detector for responding to scintillation events and event detection and recordation circuitry configurable to detect and record SPECT image information or PET image information, a method of generating a nuclear medicine image, said method comprising the steps of:

configuring said first and said second detectors at a 90 degree orientation;
performing a transmission scan of an object about a plurality of rotation angles to collect transmission projection information;
configuring said dual SPECT/PET mode of operation camera system for a PET imaging mode of operation;
configuring said first and second detectors at a 180 degree orientation;
imaging said object with said first detector and said second detector about a plurality of rotation angles to collect PET emission projection information;
correcting for nonuniform attenuation by correcting said PET emission projection information by said transmission projection information;
and
responsive to said step of correcting, reconstructing a PET image with corrected PET emission projection information to produce a PET reconstruction.

5 more elements

In a dual SPECT/PET mode of operation nuclear camera system including at least a first detector and a second detector responsive to scintillation events, and event detection and recordation circuitry configurable to detect and record SPECT image information or PET image information, a method of generating a nuclear medicine image comprising the steps of:

configuring said first and second detectors at a 90 degree orientation;
configuring said dual SPECT/PET operation camera system for a SPECT imaging mode of operation;
performing a transmission scan of an object about a plurality of rotation angles to collect transmission projection information;
imaging said object with said first detector and said second detector about a plurality of rotation angles to collect SPECT emission projection information;
correcting for nonuniform attenuation by correcting said SPECT emission projection information by said transmission projection information;
and
responsive to said step of correcting, reconstructing a SPECT image with corrected SPECT emission projection information to produce a SPECT reconstruction.

4 more elements

In a multi-detector dual SPECT/PET operation nuclear camera system including at least a first detector and a second detector responsive to scintillation events, and event detection and recordation circuitry configurable to detect and record SPECT image information or PET image information, a method of generating a nuclear medicine image comprising the steps of:

configuring said first and second detectors at a 90 degree configuration;
performing a transmission scan of an object about a plurality of rotation angles to collect transmission projection information;
configuring said dual SPECT/PET operation camera system for simultaneous acquisition of both PET and SPECT event data;
imaging said object with said first detector and said second detector about a plurality of rotation angles to simultaneously collect both SPECT and PET emission projection information;
correcting both said SPECT and said PET emission projection information for nonuniform attenuation using said transmission projection information to generate corrected SPECT emission projection information and corrected PET emission projection information;
and
reconstructing a SPECT image with said corrected SPECT emission projection information to produce a SPECT reconstruction;
reconstructing a PET image with said corrected PET emission projection information to produce a PET reconstruction.

5 more elements

A nuclear camera system comprising:

(a) a user selectable operational mode between PET imaging and SPECT imaging;
(b) a pair of scintillation detectors for reporting a pair of events occurring in coincidence for said PET imaging and for reporting events individually for said SPECT imaging, each of said pair of scintillation detectors including:
an array of photomultipliers, individual photomultipliers for generating output channel signals indicative of energy detected by said individual photomultipliers, wherein said array of photomultipliers is divided into zones;
a first plurality of event detection circuits wherein each of said event detection circuits receive channel signals from a particular zone of said zones of said array of photomultipliers;
and
a first trigger circuit coupled to said first plurality of event detection circuits for generating a trigger signal upon receiving an event indication from any event detection circuit of said first plurality of event detection circuits;
(c) a nonuniform attenuation correction mechanism including transmission radiation sources for scanning said first detector and said second detector with transmission radiation, wherein said circuitry reports and stores transmission information while said transmission radiation sources are scanning;
(d) a computer system for generating a PET reconstruction based on said PET events which are corrected by said transmission information, said computer system is also for generating a SPECT reconstruction based on said SPECT events which are corrected by said transmission information.

5 more elements

Dependencies are inferred from the claim text.

Multi-head nuclear medicine camera for dual SPECT and PET imaging with monuniform attenuation correction

Life of this patent

Multi-head nuclear medicine camera for dual SPECT and PET imaging with monuniform attenuation correction

Life of this patent

Abstract

Claims36