Optically coupled readout front-end for imaging system

• US 20090093710A1
• Filed: 10/06/2008
• Published: 04/09/2009
• Est. Priority Date: 10/04/2007
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Levin, Craig S., Olcott, Peter D.
• Granted Patent: US 8,868,154 B2
• Time in Patent Office: Days
• US Class Current: 600/411
• CPC Class Codes: G01R 33/481 MR combined with positron emission tomography [PET] or single photon emission computed tomography [SPECT]

Abstract

A front end for an imaging system. The front end comprises at least one magnetically-insensitive high-energy photon detector and an interface for converting an output of the at least one high-energy photon detector to an optical signal and transmitting the optical signal. A receiver is optically coupled to the interface to receive the optical signal and convert the optical signal into a voltage signal.

Claims

1. A front end for an imaging system comprising:

a magnetically-insensitive high energy photon detector configured to receive emitted photons and produce an output;

an interface coupled to said high energy photon detector for converting an output of said high energy photon detector to an optical signal; and

a transmitter coupled to said interface for transmitting said optical signal.

2. The front end of claim 1, wherein the output comprises a non-optical output.

3. The front end of claim 1, wherein the output comprises a charge.

4. The front end of claim 1, wherein said high energy photon detector comprises:

at least one scintillation crystal for receiving emitted photons and producing a signal; and

at least one photodiode for receiving the produced signal and producing the output.

5. The front end of claim 1, wherein said high energy photon detector comprises a direct interaction semiconductor configured to receive emitted photons and produce the output.

6. The front end of claim 1, wherein said interface comprises:

an amplifier coupled to said high energy photon detector and configured to convert the output of the high energy photon detector to a voltage;

a driver coupled to said amplifier and configured to receive the voltage and drive said transmitter.

7. The front end of claim 6, wherein said driver comprises a laser driver;

and

wherein said transmitter comprises a laser diode.

8. The front end of claim 6, wherein said amplifier comprises a charge sensitive preamplifier.

9. The front end of claim 1, further comprising:

an optical coupler, said optical coupler being coupled to said transmitter for coupling the transmitted optical signal to a receiver.

10. The front end of claim 1, wherein said high energy photon detector comprises:

a plurality of scintillation crystals for receiving emitted photons and producing a plurality of signals; and

at least one photodiode for receiving the produced signals and producing the output;

wherein the number of scintillation crystals is greater than the number of photodiodes.

11. A front end module for an imaging system that is located in a high magnetic field environment, comprising:

at least one magnetically-insensitive high-energy photon detector;

an interface for converting an output of said at least one high-energy photon detector to an optical signal and transmitting the optical signal; and

a receiver optically coupled to said interface for receiving the optical signal and converting the optical signal into a voltage signal.

12. The front end module of claim 11, wherein said interface comprises an amplifier and a diode.

13. The front end module of claim 11, wherein said interface comprises:

a charge sensitive preamplifier configured to convert the output of said at least one high-energy photon detector to a voltage;

a laser driver configured to convert the voltage to a current; and

a laser diode configured to receive the current and generate the optical signal.

14. The front end module of claim 11, wherein said at least one high-energy photon detector and said interface are disposed within an MRI system, and wherein said receiver is disposed outside of the MRI system.

15. The front end module of claim 11, wherein said at least one high energy photon detector comprises:

at least one scintillation crystal for receiving emitted photons and producing a signal; and

at least one photodiode for receiving the produced signal and producing the output.

16. The front end module of claim 11, wherein said interface is magnetically insensitive.

17. The front end module of claim 11, further comprising:

an optical coupler for optically coupling said interface and said receiver.

18. The front end module of claim 17, wherein said optical coupler comprises at least one optical fiber.

19. A PET system comprising:

the front end module of claim 11; and

electronics for converting the voltage from said receiver and generating an image from the voltage.

20. An imaging system comprising:

the PET system of claim 19; and

an MRI system.

21. A front end for an imaging system comprising:

means for receiving emitted photons and generating an amplified optical signal, said means for receiving emitted photons being disposed inside an MRI system;

means for receiving the optical signal and generating a voltage signal, said means for receiving the optical signal being disposed outside a MRI system; and

means for optically coupling said means for receiving emitted photons and said means for receiving the optical signal.

22. A method for imaging comprising:

within an MRI system;

generating emitted photons within a body;

receiving the emitted photons;

amplifying the received photons; and

transmitting the amplified photons as an optical signal;

outside the MRI system;

receiving the transmitted optical signal;

converting the received optical signal to a voltage; and

generating an image of at least part of the body based on the voltage.

23. The method of claim 22, further comprising:

imaging at least part of the body using the MRI system simultaneously with said receiving the emitted photons and transmitting the optical signal.