Background: The positron emission tomography (PET) ligand 68 Ga-Glu-urea-Lys(Ahx)-HBED-CC (68 Ga-PSMA-11) targets the prostate-specific membrane antigen (PSMA), upregulated in prostate cancer cells. Although 68 Ga-PSMA-11 PET is widely used in research and clinical practice, full kinetic modeling has not yet been reported nor have simplified methods for quantification been validated. The aims of our study were to quantify 68 Ga-PSMA-11 uptake in primary prostate cancer patients using compartmental modeling with arterial blood sampling and to validate the use of standardized uptake values (SUV) and image-derived blood for quantification. Results: Fifteen patients with histologically proven primary prostate cancer underwent a 60-min dynamic 68 Ga-PSMA-11 PET scan of the pelvis with axial T1 Dixon, T2, and diffusion-weighted magnetic resonance (MR) images acquired simultaneously. Time-activity curves were derived from volumes of interest in lesions, normal prostate, and muscle, and mean SUV calculated. In total, 18 positive lesions were identified on both PET and MR. Arterial blood activity was measured by automatic arterial blood sampling and manual blood samples were collected for plasmato-blood ratio correction and for metabolite analysis. The analysis showed that 68 Ga-PSMA-11 was stable in vivo. Based on the Akaike information criterion, 68 Ga-PSMA-11 kinetics were best described by an irreversible two-tissue compartment model. The rate constants K 1 and k 3 and the net influx rate constants K i were all significantly higher in lesions compared to normal tissue (p < 0.05). K i derived using image-derived blood from an MR-guided method showed excellent agreement with K i derived using arterial blood sampling (intraclass correlation coefficient = 0.99). SUV correlated significantly with K i with the strongest correlation of scan time-window 30-45 min (rho 0.95, p < 0.001). Both K i and SUV correlated significantly with serum prostate specific antigen (PSA) level and PSA density. Conclusions: 68 Ga-PSMA-11 kinetics can be described by an irreversible two-tissue compartment model. An MR-guided method for image-derived blood provides a non-invasive alternative to blood sampling for kinetic modeling studies. SUV showed strong correlation with K i and can be used in routine clinical settings to quantify 68 Ga-PSMA-11 uptake.

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In recent years, medical imaging with hybrid techniques has widely accepted and employed in clinical routine. PET/MRI offers significant advantages, including excellent contrast and resolution and reduced ionizing radiation, as compared to well-established PET/CT. Therefore, PET/MRI is a promising modality for oncologic imaging of some regions, such as brain, head and neck, liver and pelvis. This article set out to analyze clinical conditions that could benefit from PET/MRI imaging based on our caseload. The potential of PET/MRI to become the imaging modality of choice for assessment of neurologic and oncologic conditions associated with soft tissues is highlighted. Clinical aspects of PET/MRI and its application to clinical cases are illustrated with examples extracted from the authors’ preliminary experience.

SUVmax from PET/CT and PET/MR are linearly correlated, on average 20% higher on PET/CT than on PET/MR and should, therefore, not be used interchangeably in patient follow-up.

PURPOSE:To investigate the effects of Borage oil on cardiac remodeling after myocardial infarction (MI). METHODS:Male Wistar rats underwent ligation of the left coronary artery and divided into three groups: MI (control), BO-18 (18 mg/ kg of borage oil) and BO-180 (180 mg/kg of borage oil). After seven days, heart was arrested in diastole and processed for histological evaluation of: MI size, LV dilation, myocyte hypertrophy, inflammatory infiltration and fibrosis in MI region and in remote region. The relative weight of the lung was used as a marker of heart failure. The MI size was comparable among groups. RESULTS:Compared to control, BO treated groups showed lower weight of heart and lungs, reduced LV dilation and myocyte hypertrophy. Hemodynamic measurements were comparable. The treatment attenuated the inflammatory infiltration and fibrosis in remote myocardium. CONCLUSION:Borage oil attenuates progression of cardiac remodeling after myocardial infarction and congestive heart failure.

Objective The aim of the study was to verify the effect of a virtual rehabilitation protocol for patients with Parkinson disease, primarily assessing striatal dopamine transporters and secondarily motor symptoms and quality of life. Design Nineteen patients with Parkinson disease underwent an 8-wk virtual rehabilitation protocol using XBOX 360S. Evaluation of dopamine transporters was performed by single-photon emission computed tomography using TRODAT-1 as the radioligand. Participants were clinically assessed using the Unified Parkinson Disease Rating Scale to quantify motor symptoms. Moreover, the Parkinson Disease Questionnaire and Short-Form Health Status Survey were used to assess quality of life and the Berg Balance Scale to assess balance. Results Regarding our primary outcome, dopamine transporter was significantly increased in the putamen contralateral to the clinically most affected body side (P = 0.034) considering preintervention and postintervention measurements. Furthermore, we observed significant improvement in Unified Parkinson Disease Rating Scale (10-point reduction, P = 0.001), Parkinson Disease Questionnaire (11.3-point reduction, P = 0.001), Short-Form Health Status Survey (“Functional capacity,” P = 0.001; “Pain,” P = 0.006; and “Mental Health” domains, P < 0.001), and Berg Balance Scale (5-point increase, P = 0.015). Conclusions In our group of Parkinson disease patients, this virtual rehabilitation protocol enabled a dopamine transporter increase in the region of the putamen contralateral to the clinically most affected body side. Moreover, motor signs and quality of life were significantly improved.

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The liver is the organ most commonly affected by colorectal cancer metastasis. Currently, liver resection is the treatment of choice, but in cases where it is not possible, intensity-modulated radiation therapy is an alternative. We report the case of a 57-year-old woman whose colorectal carcinoma metastasized to the liver. She was referred for implantation of fiducial markers for intensity-modulated radiation therapy planning. PET-CT stands out as an additional tool for distinguishing metabolically active tumor tissue from other tissues, ensuring effective introduction of percutaneous fiducial markers, especially in cases where use of conventional imaging techniques is limited.