Flat scintillation gamma camera, with very high spatial resolution, with modular structure

• US 6,232,605 B1
• Filed: 12/22/1998
• Issued: 05/15/2001
• Est. Priority Date: 05/02/1997
• Status: Expired due to Term

• Current Assignee: Cnr-Consiglio Nazionale Delle Ricerche
• Original Assignee: Cnr-Consiglio Nazionale Delle Ricerche
• Inventors: Pani, Roberto, Soluri, Alessandro
• Primary Examiner(s): Hannaher, Constantine
• Assistant Examiner(s): Gabor, Otilia
• Application Number:
  US09/202,790
• Time in Patent Office: 875 Days
• Field of Search: 250/366, 250/367, 250/363.02
• US Class Current: 250/366
• CPC Class Codes: A61B 6/037 Emission tomography
• CPC Class Codes: A61B 6/4258 for detecting non x-ray radiation, e.g. gamma radiation A61B6/037 takes precedence
• CPC Class Codes: G01T 1/1642 using a scintillation crystal and position sensing photodetector arrays, e.g. ANGER cameras

Abstract

The gamma camera, able to be developed in areas of any size and unlimited, presents such a thickness as to be considered flat and of minimal bulk and it can be assembled in individual modules to be attached one to the other solving the problem of dead zones between individual PSPMTS, with values of intrinsic spatial resolution in the order of 1 mm. The application of the present invention may range from the medical field (PET, SPECT, SPEM, PEM, etc.) to employment in astrophysics.

Claims

1. A flat scintillation gamma camera with very high spatial resolution, comprising a collimator (1), a scintillating crystal (2), a cladding (3), and a device able to collect optical signals produced by the scintillation crystal and amplified into electrical signals, wherein said device able to collect optical signals produced by the scintillation crystal and amplified into electrical signals comprises a plurality of square-shaped Position Sensitive Photo-Multiplier Tubes (PSPMT'"'"'s) disposed adjacent one another, each PSPMT having a plurality of groups of collecting wires, with at least one group of collecting wires of each PSPMT being conductively connected to a group of collecting wires of an adjacent PSPMT, for calculation of X and Y positions;

each said PSPMT having a side greater than 20 mm and a dead zone with a contiguous PSPMT smaller than 8 mm.

2. The flat scintillation gamma camera according to claim 1, wherein one said PSPMT has wires not connecting with analogous wires of a contiguous PSPMT.

3. The flat scintillation gamma camera according to claim 1, wherein said multiple square-shaped PSPMTs constitute an area of detection with a polygonal profile.

4. The flat scintillation gamma camera according to claim 1, comprising an operational amplifier (8) Performing hardware operations on input signals for the computation of a charge barycenter to take place via a weighted sum method, as represented by a formula for the barycenter.

5. The flat scintillation gamma camera according to claim 1, comprising an operational amplifier (8) performing hardware rations on the input signals having weighted resistance collection of charge in position of the dead zone, for computation of the charge barycenter taking place via a weighted sum method as represented by a formula for the barycenter.

6. The flat scintillation gamma camera according to claim 1, wherein each said PSPMT has a width (FWHM) at least as great as the interspace between contiguous PSPMT'"'"'s and an anode sampling pitch.

7. The flat scintillation gamma camera according to claim 1, wherein each said PSPMT has a side not greater than 30 mm.

8. The flat scintillation gamma camera according to claim 7, wherein each said PSPMT has a side not greater than 22 mm.

9. The flat scintillation gamma camera according to claim 8, wherein each said PSPMT has a thickness not greater than 50 mm.

10. The flat scintillation gamma camera according to claim 7, wherein each said PSPMT has a thickness not greater than 50 mm.