Foreign Body Perforating the Descending Colon Incidentally Detected on 18F-FDG PET/CT.

A 78-year-old woman was diagnosed having unresectable tongue cancer 6 months ago, for which she received radiation therapy. She was on enteral nutrition for more than 2 months due to dysphagia and underwent an 18F-FDG PET/CT for restaging. The images showed uptake in a left cervical node.

Correlation of F-sodium fluoride uptake and radiodensity in extraosseous metastases of medullary thyroid carcinoma.

Objective: Although F-sodium fluoride (F-NaF) uptake is frequently observed in extraosseous metastases of medullary thyroid carcinoma (MTC) with calcification, itcan also occur in metastatic sites without visible calcium deposition, leading to the hypothesis that visually undetectable calcium accumulation may be responsible for this uptake. The aim of this study was to indirectly support this hypothesis by analyzing the correlation between the degree of F-NaF uptake and radiodensity in extraosseous MTC metastases, since calcium deposition can increase attenuation even when not visually detectable.

Subjects And Methods: Extraosseous metastatic lesions of 15 patients with MTC were evaluated using F-NaF positron-emission tomography (PET)/computed tomography (CT)and segmented by levels of standardized uptake value (SUV).

Repeatability of brown adipose tissue activation measured by [F]FDG PET after beta3-adrenergic stimuli in a mouse model.

Unlabelled: This study aimed to evaluate the repeatability of brown adipose tissue (BAT) activation measured by [F]FDG-PET after beta3-adrenergic stimuli with CL316243 in mice.

Methods: Male C57BL/6 mice underwent [F]FDG-PET at baseline without stimulation (T0-NS), on three consecutive days after intravenous administration of the selective β3-adrenergic agonist CL316243 (T1-CL, T2-CL, T3-CL), and without stimuli after 1 and 2 weeks (T7-NS and T14-NS). The standardized uptake value (SUVmax), BAT metabolic volume (BMV), and total BAT glycolysis (TBG) were measured in each scanning session, with statistical groupwise comparisons by ANOVA and post hoc Tukey test.

Validation of automated image co-registration integrated into in-house software for voxel-based internal dosimetry on single-photon emission computed tomography images.

Objective: To develop an automated co-registration system and test its performance, with and without a fiducial marker, on single-photon emission computed tomography (SPECT) images.

Materials And Methods: Three SPECT/CT scans were acquired for each rotation of a Jaszczak phantom (to 0°, 5°, and 10° in relation to the bed axis), with and without a fiducial marker. Two rigid co-registration software packages-SPM12 and NMDose-coreg-were employed, and the percent root mean square error (%RMSE) was calculated in order to assess the quality of the co-registrations.

[F]FDG and [C]PK11195 PET imaging in the evaluation of brown adipose tissue - effects of cold and pharmacological stimuli and their association with crotamine intake in a male mouse model.

Unlabelled: This study aimed to evaluate the role of positron emission tomography (PET) with [C]PK11195 and [F]FDG in the characterization of brown adipose tissue (BAT).

Methods: Male C57BL/6 mice were studied with the glucose analogue [F]FDG (n = 21) and the TSPO mitochondrial tracer [C]PK11195 (n = 28), without stimulus and after cold (6-9 °C) or beta-agonist (CL316243) stimuli. PET studies were performed at baseline and after 21 days of daily treatment with crotamine, which is a peptide described to induce adipocyte tissue browning and to increase BAT metabolism.

Comparison of Oral and IV 18 F-NaF PET/CT Administration in the Assessment of Bone Metastases in Patients With Breast or Prostate Cancers.

Purpose: The aim of this study was to compare oral and IV administrations of 18 F-NaF PET/CT for detection of suspicious bone metastatic lesions of breast and prostate cancers.

Patients And Methods: Thirty-six patients with breast (n = 23) or prostate (n = 13) cancers and high risk for bone metastases were prospectively evaluated. All patients underwent 2 PET/CT studies after IV and oral 18 F-NaF administration within a 2 to 23 days interval between them.

Radiation safety measures in diagnostic nuclear medicine, based on the potential radiation dose emitted by radioactive patients.

Objective: To measure the potential radiation dose emitted by patients who have recently undergone diagnostic nuclear medicine procedures, in order to establish optimal radiation safety measures for such procedures.

Materials And Methods: We evaluated the radiation doses emitted by 175 adult patients in whom technetium-99m, iodine-131, and fluorine-18 radionuclides were administered for bone, kidney, heart, brain, and whole-body scans, as measured with a radiation detector. Those values served as the basis for evaluating whole-body radiopharmaceutical clearance, as well as the risk for the exposure of others to radiation, depending on the time elapsed since administration of the radiopharmaceutical.

Potential of [C]()-PK11195 PET Imaging for Evaluating Tumor Inflammation: A Murine Mammary Tumor Model.

Background: Breast tumor inflammation is an immunological process that occurs mainly by mediation of Tumor-Associated Macrophages (TAM). Aiming for a specific measurement of tumor inflammation, the current study evaluated the potential of Positron Emission Tomography (PET) imaging with [C]()-PK11195 to evaluate tumor inflammation in a mammary tumor animal model.

Methods: Female Balb/C mice were inoculated with 4T1 cells.

Brown fat triglyceride content is associated with cardiovascular risk markers in adults from a tropical region.

Brown adipose tissue (BAT) is regarded as an interesting potential target for the treatment of obesity, diabetes, and cardiovascular diseases, and the detailed characterization of its structural and functional phenotype could enable an advance in these fields. Most studies evaluating BAT structure and function were performed in temperate climate regions, and we are yet to know how these findings apply to the 40% of the world's population living in tropical areas. Here, we used F-fluorodeoxyglucose positron emission tomography - magnetic resonance imaging to evaluate BAT in 45 lean, overweight, and obese volunteers living in a tropical area in Southeast Brazil.

In-depth cardiovascular and pulmonary assessments in children with multisystem inflammatory syndrome after SARS-CoV-2 infection: A case series study.

We assessed PET-CT myocardial blood flow (MBF) using N-13 ammonia, brachial flow-mediated dilation, and cardiopulmonary exercise test in five post-discarged MIS-C survivors. None of the patients (median age: 9, range: 7-18 years; 3 females; 2 males) had preexisting pediatric chronic conditions. At the follow-up visit, two patients exhibited severe perfusion defect developed in the left ventricular cavity, suggesting extensive myocardial ischemia (MBF <2.

Whole Skeletal Mean SUV Measured on F-NaF PET/CT Studies as a Prognostic Indicator in Patients with Bone Metastatic Breast Cancer.

In this work we assessed the association between the whole skeletal mean standardized uptake value (SUV) measured on F-NaF PET/CT studies and the overall survival (OS) of bone metastatic breast cancer patients. We retrospectively analyzed 176 patients with breast cancer and bone metastatic disease who performed F-NaF PET/CT studies. The outcomes of the patients (dead or alive) were established based on the last information available on their files.

Ga-PSMA PET/CT: effect of external cooling on salivary gland uptake.

Objective: To evaluate the effect that external cooling of the salivary glands (ECSG) has on the uptake of gallium-68-labeled prostate-specific membrane antigen (Ga-PSMA), as an indirect assessment of the capacity of ECSG to reduce the local dose in lutetium-177-PSMA-617 radioligand therapy.

Materials And Methods: Ten patients with prostate cancer were submitted to Ga-PSMA positron emission tomography/computed tomography with unilateral ECSG. The ECSG was started at 30 min before the injection of the radiotracer and maintained until the end of image acquisition (1 h after injection).

Comparison of F-NaF PET/CT with Other Imaging Methods in the Detection of Bone Metastases in Patients with Medullary Thyroid Cancer: a Report of a Series of 31 Cases.

Purpose: To compare the F-NaF PET/CT studies (F-NaF) with other imaging methods in the detection of skeletal metastases (SM) in patients with medullary thyroid cancer (MTC).

Methods: We retrospectively analyzed 31 patients with MTC who performed F-NaF to assess SM. The results of the F-NaF were compared with other imaging methods performed for metastasis detection: Tc-MDP bone scan (BS), magnetic resonance imaging (MRI), contrast-enhanced CT (CT), and Ga-Dotatate and F-FDG PET/CT studies.

68Ga-Prostate-Specific Membrane Antigen PET/CT Uptake in Intraventricular Meningioma in the Choroid Plexus.

A 68-year-old man in whom a prostate cancer biochemical recurrence was being investigated was referred for a full-body Ga-prostate-specific membrane antigen PET/CT. Focal uptake in a lesion on the choroid plexus projection was detected. Patient had no neurological complaints.

Short Dietary Intervention with Olive Oil Increases Brown Adipose Tissue Activity in Lean but not Overweight Subjects.

Background: The brown adipose tissue (BAT) is a potential target for the treatment of obesity and metabolic disorders. Its activation by cold exposure or adrenergic drugs can increase systemic insulin sensitivity and improve lipid metabolism; however, little is known about the effects of specific dietary components on BAT activity.

Objectives: We asked if a short-term (4 weeks) dietary intervention with olive oil could modify BAT activity in lean and overweight/obese volunteers.

Ultrasonography Echotexture as a surrogate for Sialadenitis secondary to 131I Radioiodine Therapy for differentiated Thyroid Cancer: a review and metaanalysis.

Unlabelled: To systematically review and analyze the medical literature to assess ultrasonography echotexture changes in thyroid cancer patients for the detection of chronic sialadenitis caused by radioiodine therapy.

Methods: Sources were retrieved from PubMed, Scopus, EMBASE and LILACS through November 2018. All studies that assessed ultrasonographic features before 131I administration and at 12 months after 131I administration were selected.

Melatonin deficiency decreases brown adipose tissue acute thermogenic capacity of in rats measured by F-FDG PET.

Objective: Melatonin has been shown to increase brown adipose tissue (BAT) mass, which can lead to important metabolic effects, such as bodyweight reduction and glycemic improvement. However, BAT mass can only be measured invasively and. The gold standard for non-invasive measurement of BAT activity is positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro-d-glucose (F-FDG PET).

Evaluation of Parotid Salivary Gland Echo Texture by Ultrasound Examinations and Correlation With Whole-Body Scintigraphy After Radioiodine Therapy in Patients With Differentiated Thyroid Carcinoma.

Objectives: This study aimed to evaluate the echo texture of the parotid salivary glands before and after radioiodine therapy (RIT) using ultrasound (US) images in patients with differentiated thyroid cancer and to evaluate the correlations between post-RIT whole-body scintigraphy (WBS) images and US image patterns in salivary and cervical areas.

Methods: A retrospective study was performed with data on demographic and clinical information, US examinations, and WBS images collected through medical recordings.

Results: Comparing the US features before and after RIT, significant echo texture heterogeneity was found in 31.

Accuracy in dosimetry of diagnostic agents: impact of the number of source tissues used in whole organ S value-based calculations.

Background: Dosimetry for diagnostic agents is performed to assess the risk of radiation detriment (e.g., cancer) associated with the imaging agent and the risk is assessed by computing the effective dose coefficient, e.

Comparison of different quantification methods for 18F-fluorodeoxyglucose-positron emission tomography studies in rat brains.

Objectives: This study aimed to evaluate several methods to estimate glucose consumption in the male Wister rat brain as measured by PET.

Methods: Fourteen male Wistar normoglycemic rats were studied. The input function consisted of seventeen blood samples drawn manually from the femoral artery.

Radionuclide therapy: current status and prospects for internal dosimetry in individualized therapeutic planning.

The efficacy and toxicity of radionuclide therapy are believed to be directly related to the radiation doses received by target tissues; however, nuclear medicine therapy continues to be based primarily on the administration of empirical activities to patients and less frequently on the use of internal dosimetry for individual therapeutic planning. This review aimed to critically describe the techniques and clinical evidence of dosimetry as a tool for therapeutic planning and the main limitations to its implementation in clinical practice. The present article is a nonsystematic review of voxel-based dosimetry.

Effects of ketamine/xylazine and isoflurane on rat brain glucose metabolism measured by F-fluorodeoxyglucose-positron emission tomography.

The aim of the present study was to investigate changes in glucose metabolism in male Wistar rats induced by the anesthetics isoflurane and ketamine combined with xylazine via F-fluorodeoxyglucose-positron emission tomography. We analyzed the differential effects of the anesthetics on F-fluorodeoxyglucose uptake and pharmacokinetics in 33 rats using quantification methods: (a) the standardized uptake value, (b) voxel-based analyses, and (c) kinetic analysis. Both anesthetics reduced glucose uptake in the entire brain.