Combined PET/MRI device, component and local coil
View Patent ↗A combined PET/MRI device is disclosed. In at least one embodiment, the PET/MRI device includes an MRI unit for exciting nuclear spins in an examination volume and for receiving signals generated by the excitation in the examination volume, and a PET unit with a detector which surrounds the examination volume at least in part and is used for detecting radiation emanating from the examination volume, with, firstly, damping of the radiation emitted by the examination volume and, secondly, undesired interactions with electromagnetic fields of the MRI unit on the components of the PET/MRI device arranged between the examination volume and the detector being avoided due to the material properties and/or structural design of the components. Corresponding components such as, for example, patient couches, bearing or support apparatuses and local coils, are both MRI and PET compatible.
1. A component of a medical imaging system, arranged between an examination volume and a detector of the imaging system during an examination, the component comprising:
materials compatible with both MRI and PET,
an outer layer of a first material having a tensile strength of >100 N/mm 2 and a modulus of elasticity of >5 kN/m 2 which encloses a filler material with a lower density or lower atomic number than the first material, wherein
the materials are not electrically conducting, are not ferromagnetic, have a dielectric constant of ∈≦2 and a dielectric loss factor of less than 0.02,
the component has an effective total radiation damping coefficient of 0.01 1/cm or less, and
the component is an antenna support for a local coil in the medical imaging system, wherein the filling material is stiffened by a cell structure, the cell structure being a honeycomb structure with walls having a thickness of a few centimeters.
2. The component of claim 1 , wherein the walls have a thickness of one millimeter or less.
3. A component of a medical imaging system, arranged between an examination volume and a first detector of the imaging system during an examination, the component comprising:
materials compatible with both MRI and PET,
an outer layer of a first material having a tensile strength of >100 N/mm 2 and a modulus of elasticity of >5 kN/m 2 which encloses a filler material with a lower density or lower atomic number than the first material, the outer layer having a thickness of one millimeter or less, wherein
the materials are not electrically conducting, are not ferromagnetic, have a dielectric constant of ∈≦2 and a dielectric loss factor of less than 0.02,
the component has an effective total radiation damping coefficient of 0.01 1/cm or less, and
the component is an antenna support for a local coil.
4. The component as claimed in claim 3 , wherein the materials compatible with both MRI and PET include materials which comprise polyamide fibers and resin.
5. The component as claimed in claim 4 , wherein the polyamide fibers and resin include epoxy resin or polyester resin.
6. The component as claimed in claim 3 , wherein the materials include materials which comprise aramid fiber tissue.
7. The component as claimed in claim 3 , wherein the materials include materials composed of composite materials.
8. The component as claimed in claim 3 , wherein the first material is aramid fiber tissue.
9. The component as claimed in claim 8 , wherein the filling material comprises rigid or flexible foam.
10. The component as claimed in claim 3 , wherein the filling material comprises rigid or flexible foam.
11. The component as claimed in claim 3 , wherein the filling material is air.
12. The component as claimed in claim 3 , wherein the antenna support is designed as a structure without any obstruction in a region of conductor tracks of an antenna of the local coil.
13. The component as claimed in claim 3 , wherein the antenna support comprises windows in a region of conductor tracks of an antenna of the local coil so that a radiation shadow on the first detector caused by the antenna is minimized.
14. The component as claimed in claim 3 , wherein the first detector is a PET detector in the medical imaging system.
15. A component of a medical imaging system, arranged between an examination volume and a first detector of the imaging system during an examination, the component comprising:
materials compatible with both MRI and PET,
an outer layer of a first material having a tensile strength of >100 N/mm 2 and a modulus of elasticity of >5 kN/m 2 which encloses a filler material with a lower density or lower atomic number than the first material, the outer layer having a thickness of one millimeter or less, wherein
the materials are not electrically conducting, are not ferromagnetic, have a dielectric constant of ∈≦2 and a dielectric loss factor of less than 0.02,
the component has an effective total radiation damping coefficient of 0.01 1/cm or less; and
a cylinder divided into two regions along a vertical axis of the cylinder, the two regions being a measuring region and an additional region,
the measuring region including the examination volume, and
the additional region including at least one of an amplifier circuit and a frequency balancing circuit.