Clinical Research Directory

All patients will be requested to have an injection of a gadolinium contrast agent, which may be either Gadavist (Bayer, Whippany, NJ, USA), Eovist (Bayer, Whippany, NJ, USA), or Dotarem (Guerbet, Princeton, NJ, USA) (ancillary drugs). * About halfway through the examination, the same intravenous catheter used to inject the radiotracer will be used to inject the MRI contrast agent; * After being positioned on the PET/MRI table, the nuclear medicine technicians will connect the patient to the MRI-safe power-injector; - The catheter will be flushed before and after injection with 0.9% saline solution;

All patients will be requested to have a radiotracer injection of Ga-PSMA (Illucix, Telix Pharmaceuticals). An intravenous catheter will be placed in an arm or hand vein for injection of the Ga-PSMA; * The catheter will be flushed post-injection with 0.9% saline solution * The injected dose and the time of injection will be recorded. * The subjects will be positioned on the scanner table; support devices under the back and/or legs will be used to enable the patient to comfortably maintain his/her position throughout the scan

PET, MRI and fused PET/MRI images will be qualitatively assessed in comparison to standard of reference data. For PET, standard of reference will be PET images as obtained by standard PET acquisition mode. Attenuation correction of the PET images will be performed using a 2-point Dixon MRI sequence and a vendor-specific atlas-based attenuation map. 3D scatter correction by single scatter simulation is also performed using the MRI-derived attenuation data. MRI images will be compared to dedicated 3 Tesla MR upper abdominal protocol images acquired at the MGH in patients with liver cirrhosis, including those undergoing imaging follow-up after systemic or local regional therapies. For PET/MRI fused images, the standard of reference will be co-registered and fused PET/MRI images as obtained by standard MRI sequences/reconstructions.