Minicamera for proximity detection of nuclear radiation emitted by a radioisotope, and its application as a surgical tool
First Claim
1. A minicamera for the detection of at least a composite β
- and γ
nuclear radiation, or a γ
nuclear radiation associated with conversion electrons assimilated with a β
radiation, emitted by a radioisotope present in a body, said minicamera having an image pick-up head comprising a β
radiation collimator which is transparent to the γ
radiation, a scintillator and a photodetector assembly, characterized in that said image pick-up head also comprises a modulating grid with holes which is arranged between the collimator and the scintillator so as to be movable by a mechanism so that in an alternating fashion it opens the holes of the collimator in a first position and closes these holes in a second position, said photodetector assembly being controlled so as to integrate the alternating signals supplied by the scintillator in said first position and said second position of the modulating grid and to apply these signals selectively to a first, open-grid image memory and to a second, closed-grid image memory, said minicamera also comprising means for calculation and comparison of signals stored in said first and second image memories in order to supply the useful image to be displayed.
2 Assignments
0 Petitions
Accused Products
Abstract
A minicamera detects at least one β and γ nuclear radiation (or assimilated) emitted by a radioisotope present in a body (1, 2). Its image pick-up head (300) includes a collimator (301), a scintillator (302) and a photodetector assembly (303 to 309). In accordance with the invention, the image pick-up head (300) also includes a modulating grid (312) with holes which is arranged between the collimator (301) and the scintillator (302). The grid can completely open or close the collimator under the influence of a suitable mechanism (313). The signals acquired by the photodetector assembly in the open position are applied to a first image memory (423) whereas those acquired in the closed position are applied to a second image memory (424). Comparison and calculation means (421) provide the desired useful signal by simple subtraction of the contents of the two memories (423, 424).
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Citations
11 Claims
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1. A minicamera for the detection of at least a composite β
- and γ
nuclear radiation, or a γ
nuclear radiation associated with conversion electrons assimilated with a β
radiation, emitted by a radioisotope present in a body, said minicamera having an image pick-up head comprising a β
radiation collimator which is transparent to the γ
radiation, a scintillator and a photodetector assembly, characterized in that said image pick-up head also comprises a modulating grid with holes which is arranged between the collimator and the scintillator so as to be movable by a mechanism so that in an alternating fashion it opens the holes of the collimator in a first position and closes these holes in a second position, said photodetector assembly being controlled so as to integrate the alternating signals supplied by the scintillator in said first position and said second position of the modulating grid and to apply these signals selectively to a first, open-grid image memory and to a second, closed-grid image memory, said minicamera also comprising means for calculation and comparison of signals stored in said first and second image memories in order to supply the useful image to be displayed. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
- and γ
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11. A method of using a minicamera in conjunction with excision of a tumor from an organism, said minicamera being configured for detection of one of composite β
- and γ
nuclear radiation emitted by a tracer radioisotope present in the organism, said minicamera having an image pick-up head comprising a radiation collimator for the one of composite β and
γ
to be detected which is transparent to the other of composite β and
γ
radiation, a scintillator and a photodetector assembly, which image pick-up head also comprises a modulating grid with holes which is arranged between the collimator and the scintillator so as to be movable between first and second positions so that it opens the holes of the collimator in the first position and closes these holes in a second position, comprising the steps of moving the modulating grid alternately between the first and second positions, integrating signals alternately supplied by the scintillator in said first and second positions of the modulating grid, calculating and comparing signals the integrated signals alternately supplied in the first and second position of the modulating grid to generate a useful image to be displayed, and applying said image pick-up head against an incision made in said organism in the course of surgery in alternation with phases of excision of the tumor.
- and γ
Specification