Methods and systems for determining a medical system alignment

1. A method of performing a patient scan using a three-dimensional (3D) cylindrical Positron Emission Tomography (PET) imaging system including a detector, said method comprising:

acquiring a count-rate profile of a brain;

repositioning at least one of a detector and the brain based on the count-rate profile and a detector sensitivity profile; and

scanning the brain when the acquired count-rate profile substantially matches the detector sensitivity profile.

2. A method in accordance with claim 1 further comprising utilizing an emitted photon distribution of the brain to acquire the count-rate profile.

3. A method in accordance with claim 1 further comprising:

acquiring a real-time count-rate profile of a brain; and

displaying the real-time count rate profile on a display.

4. A method in accordance with claim 1 further comprising visually determining when the acquired count-rate profile substantially matches the sensitivity profile of a detector.

5. A method in accordance with claim 1 further comprising utilizing an algorithm to determine when the acquired count-rate profile substantially matches the sensitivity profile of a detector.

6. A method in accordance with claim 1 wherein the detector has a substantially triangular-shaped sensitivity profile, said method further comprising repositioning the brain until the acquired count-rate profile substantially matches a ring detector sensitivity profile.

7. A method in accordance with claim 1 further comprising automatically repositioning a ring detector until the acquired count-rate profile substantially matches a sensitivity profile of the ring detector.

8. A method in accordance with claim 1 further comprising:

positioning a patient in a sitting position, and

acquiring a count-rate profile of a brain while the patient is in the sitting position.

9. A method in accordance with claim 1 further comprising:

acquiring the count-rate profile of the brain during a pre-scan; and

performing a second scan when the acquired count-rate profile substantially matches the sensitivity profile of the detector, the pre-scan being conducted for a first time, the second scan being conducted for a second time that is greater than the first time.

10. A method in accordance with claim 1 further comprising repositioning at least one of the detector and the brain until the acquired count-rate profile has a substantially triangular shape that substantially matches a sensitivity profile of the detector.

11. A method in accordance with claim 1 further comprising:

acquiring a count-rate profile of the brain that is based on an emitted photon distribution of the brain;

generating at least one histogram that is based on the count-rate profile; and

visually determining when the count-rate profile substantially matches the detector sensitivity profile using the at least one histogram.

12. A three-dimensional (3D) Positron Emission Tomography (PET) imaging system comprising a ring detector and a detector alignment module coupled to the ring detector, wherein the detector alignment module is programmed to:

receive a count-rate profile of a brain;

reposition a ring detector based on the count-rate profile and a detector sensitivity profile; and

scan the brain when the acquired count-rate profile substantially matches the detector sensitivity profile.

13. A PET imaging system in accordance with claim 12 , wherein the ring detector is configured to generate a count-rate profiled based on an emitted photon distribution of the brain.

14. A PET imaging system in accordance with claim 12 , wherein the PET imaging system is further configured to:

acquire a real-time count-rate profile of a brain; and

display the real-time count rate profile on a display.

15. A PET imaging system in accordance with claim 12 , wherein the detector alignment module is further programmed to determine when the acquired count-rate profile substantially matches the detector sensitivity profile.

16. A PET imaging system in accordance with claim 12 , wherein the detector alignment module is further programmed to reposition a ring detector until the acquired count-rate profile acquired from the ring detector substantially matches a triangular-shaped sensitivity profile of the ring detector.

17. A PET imaging system in accordance with claim 12 , wherein the detector alignment module is further programmed

acquire the count-rate profile of the brain during a pre-scan; and

initiate a second scan when the acquired count-rate profile substantially matches the sensitivity profile of the ring detector, the second scan being conducted for a time that is greater than a time used to conduct the pre-scan.

18. A non-transitory computer readable medium encoded with a program to instruct a computer to:

receive a count-rate profile of a brain;

reposition a ring detector based on the count-rate profile and a detector sensitivity profile; and

scan the brain when the acquired count-rate profile substantially matches the detector sensitivity profile.

19. A non-transitory computer readable medium in accordance with claim 18 wherein the program further instructs a computer to generate a count-rate profiled based on an emitted photon distribution of the brain.

20. A non-transitory computer readable medium in accordance with claim 18 wherein the program further instructs a computer to:

acquire a real-time count-rate profile of a brain; and

display the real-time count rate profile on a display.