Patent ID: 8791437

Claim:
Electron beam shaping device suitable for a machine for intraoperative radiation therapy (IORT—Intra Operative Radiation Therapy), said machine comprising a mobile unit, provided with a linear accelerator having an electrons radiating head, and an operating control rack, which are wired connected to each other, said shaping device including a circular applicator, comprising a cylindrical tube and having a duct through which the electron beam is transmitted, which is rigidly attached to said radiating head and which includes a proximal element, that is attached to said radiating head, and a distal element ( 3 ), that is placed in contact with the area to radiate and that is attached to said proximal element, the shaping device being characterised in that it comprises: a slab ( 1 ), which is removably attached to said distal element ( 3 ) and which is provided with a hole ( 2 ) corresponding to the duct of the circular applicator, at least two planar elements ( 10 ), whereby each planar element ( 10 ) comprises two overlapping plates ( 11 , 12 ) which are attached to each other through first mechanical coupling means ( 13 ) and whereby each planar element ( 10 ) is attached to said slab ( 1 ) in a variable position with continuity as a function of the attachment position of said first mechanical coupling means ( 13 ) and of second mechanical coupling means ( 14 ), said at least two planar elements ( 10 ) being reciprocally arranged so as to be adjacent to each other and each planar element ( 10 ) sliding with respect to another adjacent planar element ( 10 ) through mechanical guide and slide means ( 12 C, 12 D), whereby the reciprocal arrangement of said at least two planar elements ( 10 ) is adjustable so as to define an aperture ( 20 ) of lower area than that of the section of the duct of said circular applicator, said two overlapping plates ( 11 , 12 ) being made of different materials, so that a first plate ( 11 ) is made of a first sterilisable material with a first atomic number and a second plate ( 12 ) is made of a second sterilisable material with a second atomic number larger than the first atomic number, whereby the second plate ( 12 ) attenuates X-rays produced by the first plate ( 11 ).