Method for determining a position-dependent attenuation map of surface coils of a magnetic resonance/PET apparatus

A magnetic resonance/PET apparatus comprising:

• at least one surface coil including a plurality of coils;
• and
• one or more processors configured to execute computer-readable instructions to determine a position-dependent attenuation map of the at least one surface coil by
• acquiring magnetic resonance image data by way of the at least one surface coil during a magnetic resonance/PET examination of a patient;
• reconstructing a position of the at least one surface coil based on the acquired magnetic resonance image data;
• determining the position-dependent attenuation map of the at least one surface coil based on the reconstructed position of the at least one surface coil;
• wherein the acquiring magnetic resonance image data includes at least one of acquiring and reconstructing individual images of the plurality of coils;
• wherein the reconstructing a position of the at least one surface coil includes determining at least one reference shape for at least one of the plurality of coils based on the individual images of the plurality of coils;
• and
• wherein the determining at least one reference shape includes
• a threshold value analysis of a signal intensity distribution in the individual images of the plurality of coils, and
• determining a focal point of the signal intensity distribution in the individual images of the plurality of coils.

A non-transitory computer-readable storage medium storing computer-readable instructions that, when executed by a programmable computing unit of a combined magnetic resonance/positron emission tomography (PET) apparatus, cause the programmable computing unit to perform a method for determining a position-dependent attenuation map of at least one surface coil of the combined magnetic resonance/PET apparatus, the at least one surface coil including a plurality of coils, and the method comprising:

• acquiring magnetic resonance image data by way of the at least one surface coil during a magnetic resonance/PET examination of a patient;
• reconstructing a position of the at least one surface coil based on the acquired magnetic resonance image data;
• determining the position-dependent attenuation map of the at least one surface coil based on the reconstructed position of the at least one surface coil;
• wherein the acquiring magnetic resonance image data includes at least one of acquiring and reconstructing individual images of the plurality of coils;
• wherein the reconstructing a position of the at least one surface coil includes determining at least one reference shape for at least one of the plurality of coils based on the individual images of the plurality of coils;
• and
• wherein the determining at least one reference shape includes
• a threshold value analysis of a signal intensity distribution in the individual images of the plurality of coils, and
• determining a focal point of the signal intensity distribution in the individual images of the plurality of coils.

A method for determining a position-dependent attenuation map of at least one surface coil of a combined magnetic resonance/positron emission tomography (PET) apparatus, the method comprising:

• acquiring magnetic resonance image data by way of the at least one surface coil during a magnetic resonance/PET examination of a patient;
• acquiring whole-body coil image data during the magnetic resonance/PET examination of the patient by way of a whole-body coil of the combined magnetic resonance/PET apparatus;
• normalizing the magnetic resonance image data based on the whole-body coil image data;
• reconstructing a position of the at least one surface coil based on at least one of the normalized magnetic resonance image data and the acquired magnetic resonance image data;
• determining the position-dependent attenuation map of the at least one surface coil based on the reconstructed position of the at least one surface coil;
• wherein the at least one surface coil includes a plurality of coils;
• wherein the reconstructing a position of the at least one surface coil includes determining at least one reference shape for at least one of the plurality of coils based on individual images of the plurality of coils;
• and
• wherein the determining at least one reference shape includes
• a threshold value analysis of a signal intensity distribution in the individual images of the plurality of coils, and
• determining a focal point of the signal intensity distribution in the individual images of the plurality of coils.

A method for determining a position-dependent attenuation map of at least one surface coil of a combined magnetic resonance/positron emission tomography (PET) apparatus, the method comprising:

• acquiring magnetic resonance image data by way of the at least one surface coil during a magnetic resonance/PET examination of a patient;
• acquiring a plurality of magnetic resonance training image datasets of at least one training object by way of the at least one surface coil, the at least one surface coil being positioned at different positions relative to at least one of a reference point of the combined magnetic resonance/PET apparatus and a reference point of the at least one training object;
• performing a principal component analysis using the plurality of magnetic resonance training image datasets as input data;
• outputting training data including results of the principal component analysis;
• reconstructing a position of the at least one surface coil based on the acquired magnetic resonance image data and the training data;
• and
• determining the position-dependent attenuation map of the at least one surface coil based on the reconstructed position of the at least one surface coil;
• wherein the at least one surface coil includes a plurality of coils;
• wherein the reconstructing a position of the at least one surface coil includes determining at least one reference shape for at least one of the plurality of coils based on individual images of the plurality of coils;
• and
• wherein the determining at least one reference shape includes
• a threshold value analysis of a signal intensity distribution in the individual images of the plurality of coils, and
• determining a focal point of the signal intensity distribution in the individual images of the plurality of coils.