Molecular imaging and biology : MIB : the official publication of the Academy of Molecular Imaging
-
Early diagnosis and therapeutic monitoring of acute osteomyelitis (AO) is challenging. Here, we use a polyethylene glycol (PEG)ylated chemotactic peptide cinnamoyl-F-(D)L-F-(D)L-F (cFLFLF) conjugated with hydrazinonicotinamide (HYNIC) and labeled with Tc-99m ([(99m)Tc]cFLFLF) to image AO in a rat model and to validate its efficacy in early diagnosis and therapeutic evaluation of AO. ⋯ Our results suggest that the specificity and image quality of [(99m)Tc]cFLFLF are superior to those of the [(99m)Tc]MDP and [(18)F]DFG imaging probes currently used for early diagnosis of AO. Furthermore, [(99m)Tc]cFLFLF was able to effectively evaluate the therapeutic response to antibiotic treatment of AO. Our data suggest that [(99m)Tc]cFLFLF is a promising imaging agent for detection of infectious diseases.
-
We compare the quantitative accuracy of magnetic resonance imaging (MRI)-based attenuation correction (AC) using the 3-class attenuation map (PET-MRAC3c) implemented on the Ingenuity TF PET/MRI and the 4-class attenuation map (PET-MRAC4c) similar to the approach used on the Siemens mMR PET/MR considering CT-based attenuation-corrected PET images (PET-CTAC) as standard of reference. ⋯ PET-MRAC3c resulted in significant systematic positive bias in the lungs owing to the lower attenuation coefficient used and negative bias in other regions. PET-MRAC4c slightly underestimated tracer uptake in the lungs and led to even larger negative bias than PET-MRAC3c in other body regions. The presence of artifacts in the MRAC might lead to misinterpretation of clinical studies. As such, the attenuation map needs to be checked for artifacts as part of the reading procedure to avoid misinterpretation of SUV measurements.
-
The aim of this study is to assess a software-based method with semiautomated correction for partial volume effect (PVE) to quantify the metabolic activity of pulmonary malignancies in patients who underwent non-gated and respiratory-gated 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG)-positron emission tomography (PET)/x-ray computed tomography(CT). ⋯ Based on this study, assessment of volumetric PET/CT parameters and partial volume effect correction for accurate quantification of lung malignant lesions by using respiratory non-gated PET images are feasible and it is comparable to gated measurements. Partial volume correction increased both the respiratory-gated and non-gated values significantly and appears to be the dominant source of quantification error of lung lesions.
-
To investigate changes in glucose brain metabolism after deep brain stimulation (DBS) in the lateral hypothalamic area (LHA) in a rat model of obesity. ⋯ DBS produced significant changes in brain regions associated with the control of food intake and the brain reward system. DBS seems to normalize the impaired hippocampal functioning that has been described in obese rats. The smaller weight gain in the DBS group suggests that this technique could be considered an option for the treatment of obesity.
-
The purpose of this study is to investigate the utility of contrast-enhanced magnetic resonance imaging (CE-MRI), diffusion-weighted MRI (DW-MRI), and (68)Ga-DOTATOC positron emission tomography/computer tomography ((68)Ga-DOTATOC PET/CT) in the assessment of response to loco-regional peptide receptor radiotherapy (PRRT) with (90)Y-/(177)Lu-DOTATOC in patients with hepatic metastases from gastro-entero-pancreatic neuroendocrine tumors (GEP-NET). ⋯ These results suggest that both DW-MRI and DOTATOC-PET imaging provide potential biomarkers for early assessment of treatment and stratification of therapy response, but that DW-MRI should be interpreted only in combination with SSTR expression and morphologic changes.