Attenuation correction and image reconstruction for hybrid MRI/PET

Attenuation correction and image reconstruction for hybrid MRI/PET

About the project

In cooperation with the Institute of Aerospace Medicine of the German Aerospace Center (DLR), we operate a hybrid MRI/PET scanner within :envihab (from the words ‘Environment’ and ‘Habitat’), a research facility to explore the effects of extreme environmental conditions on humans. Combined Positron Emission Tomography (PET) and magnetic resonance imaging (MRI) using hybrid PET/MRI scanners offers unique chances to contribute to a better understanding of processes in basic brain research and to improve the understanding of pathophysiological mechanisms of neurological and psychiatric diseases. While PET provides metabolic information, MRI can provide anatomic information as well as information about physiological parameters, water diffusion, metabolite concentrations etc. Simultaneous acquisition of MRI and PET data correlates the data of the two complementary modalities both spatially as well as temporally and allows multifunctional and multiparametric imaging.

Methodological aspects

In spite of the concurrent MRI acquisition, the PET image quality and quantitative accuracy needs to meet the standards which are currently obtained with stand-alone PET or PET/CT. A major issue for artifact-free and quantitative PET imaging is the need to correct for the attenuation of photons in the body as well as in MRI coils and patient table. An accurate attenuation map is therefore essential for proper attenuation correction. Hybrid MRI/PET allows also to use the anatomical information from MRI within the PET image reconstruction.

Partners

• Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
• Siemens MR, Siemens Healthcare, Erlangen, Germany