PET-CT reveals increased intestinal glucose uptake after gastric surgery.

Background: Mechanisms of metabolic improvement after bariatric surgery remain incompletely understood. Intestinal glucose uptake is increased after gastric bypass in rodents, potentially contributing to reduced blood glucose and type 2 diabetes remission.

Objective: We assessed whether intestinal glucose uptake is increased in humans after gastric surgery.

Kinetics of human brown adipose tissue activation and deactivation.

Brown adipose tissue (BAT) has been identified as a potential target in the treatment and prevention of obesity and metabolic disease. The precise kinetics of BAT activation and the duration of stimulus required to recruit metabolically active BAT, and its subsequent deactivation, are not well-understood. In this clinical trial, 19 healthy adults (BMI: 23.

Mapping of human brown adipose tissue in lean and obese young men.

Human brown adipose tissue (BAT) can be activated to increase glucose uptake and energy expenditure, making it a potential target for treating obesity and metabolic disease. Data on the functional and anatomic characteristics of BAT are limited, however. In 20 healthy young men [12 lean, mean body mass index (BMI) 23.

Variable Cold-Induced Brown Adipose Tissue Response to Thyroid Hormone Status.

Background: In addition to its role in adaptive thermogenesis, brown adipose tissue (BAT) may protect from weight gain, insulin resistance/diabetes, and metabolic syndrome. Prior studies have shown contradictory results regarding the influence of thyroid hormone (TH) levels on BAT volume and activity. The aim of this pilot study was to gain further insights regarding the effect of TH treatment on BAT function in adult humans by evaluating the BAT mass and activity prospectively in six patients, first in the hypothyroid and then in the thyrotoxic phase.

Activation of human brown adipose tissue by a β3-adrenergic receptor agonist.

Increasing energy expenditure through activation of endogenous brown adipose tissue (BAT) is a potential approach to treat obesity and diabetes. The class of β3-adrenergic receptor (AR) agonists stimulates rodent BAT, but this activity has never been demonstrated in humans. Here we determined the ability of 200 mg oral mirabegron (Myrbetriq, Astellas Pharma, Inc.

Rifaximin suppresses background intestinal 18F-FDG uptake on PET/CT scans.

Background: Identification of cancer or inflammatory bowel disease in the intestinal tract by PET/computed tomography (CT) imaging can be hampered by physiological uptake of F-fluorodeoxyglucose (F-FDG) in the normal colon. Previous work has localized this F-FDG uptake to the intestinal lumen, predominantly occupied by bacteria. We sought to determine whether pretreatment with an antibiotic could reduce F-FDG uptake in the healthy colon.

Quantification of human and rodent brown adipose tissue function using 99mTc-methoxyisobutylisonitrile SPECT/CT and 18F-FDG PET/CT.

Unlabelled: For brown adipose tissue (BAT) to be effective at consuming calories, its blood flow must increase enough to provide sufficient fuel to sustain energy expenditure and also transfer the heat created to avoid thermal injury. Here we used a combination of human and rodent models to assess changes in BAT blood flow and glucose utilization.

Methods: (99m)Tc-methoxyisobutylisonitrile (MIBI) SPECT (n = 7) and SPECT/CT (n = 74) scans done in adult humans for parathyroid imaging were reviewed for uptake in regions consistent with human BAT.

Sources of apical defects on a high-sensitivity cardiac camera: experiences from a practice performance assessment.

Unlabelled: Apical perfusion artifacts seen on a high-sensitivity camera warranted a practice performance assessment to evaluate contributions from soft-tissue attenuation, patient positioning, and image processing techniques.

Methods: Cardiac perfusion studies (n = 534) spanning 5 mo were retrospectively reviewed. Images were acquired with the patient in the upright position, and attenuation correction was used.

Cold but not sympathomimetics activates human brown adipose tissue in vivo.

As potential activators of brown adipose tissue (BAT), mild cold exposure and sympathomimetic drugs have been considered as treatments for obesity and diabetes, but whether they activate the same pathways is unknown. In 10 healthy human volunteers, we found that the sympathomimetic ephedrine raised blood pressure, heart rate, and energy expenditure, and increased multiple circulating metabolites, including glucose, insulin, and thyroid hormones. Cold exposure also increased blood pressure and energy expenditure, but decreased heart rate and had little effect on metabolites.

Focal physiologic fluorodeoxyglucose activity in the gastrointestinal tract is located within the colonic lumen.

Aim: Physiologic activity of 18F-fluorodeoxyglucose (FDG) in the intestinal tract occurs frequently in patients undergoing PET/computed tomography (CT) imaging, appearing most often in the colon. The purpose of this study is to determine the localization of the FDG within the colon. We hypothesize that intestinal FDG activity is intraluminal.

Respiratory gating enhances imaging of pulmonary nodules and measurement of tracer uptake in FDG PET/CT.

Objective: The aim of this study was to evaluate prospectively the effects of respiratory gating during FDG PET/CT on the determination of lesion size and the measurement of tracer uptake in patients with pulmonary nodules in a clinical setting.

Subjects And Methods: Eighteen patients with known pulmonary nodules (nine women, nine men; mean age, 61.4 years) underwent conventional FDG PET/CT and respiratory-gated PET acquisitions during their scheduled staging examinations.

Identification and importance of brown adipose tissue in adult humans.

Background: Obesity results from an imbalance between energy intake and expenditure. In rodents and newborn humans, brown adipose tissue helps regulate energy expenditure by thermogenesis mediated by the expression of uncoupling protein 1 (UCP1), but brown adipose tissue has been considered to have no physiologic relevance in adult humans.

Methods: We analyzed 3640 consecutive (18)F-fluorodeoxyglucose ((18)F-FDG) positron-emission tomographic and computed tomographic (PET-CT) scans performed for various diagnostic reasons in 1972 patients for the presence of substantial depots of putative brown adipose tissue.

Retrospective study of coronary uptake of 18F-fluorodeoxyglucose in association with calcification and coronary artery disease: a preliminary study.

Objective: To determine whether focal 18F-fluorodeoxyglucose (FDG) uptake could be detected along the course of coronary arteries in patients with known coronary artery disease (CAD) and/or coronary artery calcification (CAC) by PET/computed tomography (CT) using a new patient preparation protocol that reduces background myocardial FDG uptake.

Materials And Methods: In this retrospective, Health Insurance Portability and Accountability Act-compliant study approved by our institutional internal review board, 60 FDG-PET/CT studies performed for noncardiac indications were reviewed and CAC and focal FDG uptake were determined. Cardiac histories were obtained.

Method for decreasing uptake of 18F-FDG by hypermetabolic brown adipose tissue on PET.

Objective: The purpose of this study was to determine whether use of a high-fat, very-low-carbohydrate protocol for preparing patients for PET decreases the frequency of (18)F-FDG uptake by hypermetabolic brown adipose tissue (BAT) on PET scans.

Materials And Methods: In this HIPAA-compliant retrospective study, 741 FDG PET/CT scans obtained during the winter months (October 1-April 30) for patients who prepared with a high-fat, very-low-carbohydrate, protein-permitted protocol were compared with 1,229 FDG PET scans obtained during the winter months for patients who prepared by fasting. FDG uptake on PET scans co-localized with regions of fat identified on the CT scans was assumed to represent hypermetabolic BAT.

Suppression of myocardial 18F-FDG uptake by preparing patients with a high-fat, low-carbohydrate diet.

Objective: Myocardial 18F-FDG uptake in PET scans in patients prepared by the usual fasting protocol may result in difficulties in interpretation because variable uptake may yield false-positive results regarding mediastinal abnormalities. We aimed to analyze, retrospectively, the effect of diet on myocardial FDG uptake.

Materials And Methods: The "fasting" group comprised 101 consecutive patients before a clinical change in the patient preparation protocol.

Shareware program for nuclear medicine and PET/CT PACS display and processing.

Objective: Many of the functions necessary for imaging and analyzing nuclear medicine studies are not available on radiology PACS. Over the past 20 years, we have developed a user-friendly, easily installed software package for nuclear medicine study analysis, display, Web access, and database storage and an integrated display for fused PET/CT. We are making this software available as free shareware that can be used without a license on any PC.

Clinical pretreatment risk factors and Ga-67 scintigraphy early during treatment for prediction of outcome of patients with aggressive non-Hodgkin lymphoma.

Background: Clinical pretreatment risk factors indicate the severity of disease in patients with aggressive non-Hodgkin lymphoma (NHL). Ga-67 scintigraphy during treatment is an early indicator of treatment-related features of lymphoma cells. The ability of risk factors and Ga-67 to predict disease outcome was compared in 139 patients with aggressive NHL.