Exploring Vessel Wall Biology In Vivo by Ultrasensitive Total-Body PET.

Ultrasensitive, high-resolution, extended-field-of-view total-body (TB) PET using the first-of-its-kind 194-cm axial-field-of-view uEXPLORER may facilitate the interrogation of biologic hallmarks of hitherto difficult-to-evaluate low-signal vessel wall pathology in cardiovascular disease. Healthy volunteers were imaged serially for up to 12 h after a standard dose of F-FDG ( = 15) or for up to 3 h after injection of a very low dose (about 5% of a standard dose;  = 15). A cohort undergoing standard F-FDG PET ( = 15) on a conventional scanner with a 22-cm axial field of view served as a comparison group.

Reduced microglia activity in patients with long-term immunosuppressive therapy after liver transplantation.

Purpose: Calcineurin inhibitors (CNI) can cause long-term impairment of brain function. Possible pathomechanisms include alterations of the cerebral immune system. This study used positron emission tomography (PET) imaging with the translocator protein (TSPO) ligand F-GE-180 to evaluate microglial activation in liver-transplanted patients under different regimens of immunosuppression.

Combined Brain-Perfusion SPECT and EEG Measurements Suggest Distinct Strategies for Speech Comprehension in CI Users With Higher and Lower Performance.

Cochlear implantation constitutes a successful therapy of inner ear deafness, with the majority of patients showing good outcomes. There is, however, still some unexplained variability in outcomes with a number of cochlear-implant (CI) users, showing major limitations in speech comprehension. The current study used a multimodal diagnostic approach combining single-photon emission computed tomography (SPECT) and electroencephalography (EEG) to examine the mechanisms underlying speech processing in postlingually deafened CI users ( = 21).

Reliable quantification of F-GE-180 PET neuroinflammation studies using an individually scaled population-based input function or late tissue-to-blood ratio.

Purpose: Tracer kinetic modeling of tissue time activity curves and the individual input function based on arterial blood sampling and metabolite correction is the gold standard for quantitative characterization of microglia activation by PET with the translocator protein (TSPO) ligand F-GE-180. This study tested simplified methods for quantification of F-GE-180 PET.

Methods: Dynamic F-GE-180 PET with arterial blood sampling and metabolite correction was performed in five healthy volunteers and 20 liver-transplanted patients.

GABA Receptors in the Mongolian Gerbil: a PET Study Using [F]Flumazenil to Determine Receptor Binding in Young and Old Animals.

Purpose: Plastic changes in the central auditory system involving the GABAergic system accompany age-related hearing loss. Such processes can be investigated with positron emission tomography (PET) imaging using [F]flumazenil ([F]FMZ). Here, [F]FMZ PET-based modeling approaches allow a simple and reliable quantification of GABA receptor binding capacity revealing regional differences and age-related changes.