A systematic review of imaging studies of human brown adipose tissue

Abstract

Brown adipose tissue (BAT) is involved in energy dissipation and has been linked to weight loss, insulin sensitivity, and reduced risk of atherosclerotic disease. BAT is found most often in the supraclavicular region, as well as mediastinal and paravertebral areas, and it is predominantly seen in young persons. BAT is activated by cold temperature and the sympathetic nervous system. In humans, BAT was initially detected via 2-deoxy-2-[ 18 F]fluorod-glucose (FDG) positron emission tomography/computed tomography (PET/CT), a high-resolution molecular imaging modality used to identify and stage malignancies. Recent studies have shown that BAT can be localized using conventional imaging modalities, such as CT or magnetic resonance imaging, as well as radiotracers used for single-photon emission CT. In this systematic review, we have summarized the evidence for BAT detection in humans using various imaging techniques.

Advantages and Limitations of the Body Mass Index (BMI) to Assess Adult Obesity

“…Although MRI does not involve ionizing radiation, it requires one to be stable in a loud and noisy environment for a long time, which can be costly, tiring, and disruptive for patients, particularly those with claustrophobia. Three-dimensional photonic scanning (3DPS), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) are comparatively costly and complex imaging tools that assess adiposity and some physiological functions [ 67 ]. Healthcare inequities are evident when one considers the cost and availability of advanced diagnostics in lower-resource settings.…”

“…Combining advanced body composition analysis with comprehensive blood variables offers a promising strategy for improving obesity assessment at the population level and advancing personalized healthcare approaches to combat obesity and its related health consequences [ 61 , 67 ]. While BMI remains a cornerstone of public health surveillance and screening efforts, its limitations necessitate the embracing of emerging technologies and adopting a multifaceted approach to body composition assessment to better address the diverse needs of populations worldwide.…”

Computed Tomography Image Analysis of Body Fat Based on Multi-Image Information

“…In human body, the classification of fat is not only subcutaneous and visceral but also white adipose tissue (WAT) and brown adipose tissue (BAT) according to its different functions. BAT is involved in energy dissipation and has been linked to weight loss, insulin sensitivity, and reduced risk of atherosclerotic disease [ 16 ]. Therefore, positron emission computed tomography (PET) has some advantages.…”

Molecular Imaging of Brown Adipose Tissue Mass

“…BAT mass is the actual weight of the tissue that is consistent with and without stimulations, such as cold exposure and beta-agonist treatment, while BAT activation, reflecting by imaging signals or functional measurement, is highly dependent on several factors, including temperature, hormones, diet, medications, and the states of the sympathetic nervous system [42][43][44][45][46][47][48]. Accurately reporting BAT mass is a tremendous challenge for imaging scientists, due to the fact that BAT mass and BAT activation are intertwined under various conditions [49,50].…”

“…Two types of techniques were defined as BAT activation imaging: (1) the techniques which could detect BAT at room temperature, but the signal was increased or decreased significantly under cold temperature or drug stimulation; (2) the techniques which could not detect BAT at thermoneutral condition unless stimulated by cold temperature or drug treatment. Although a number of prior reviews have discussed imaging of BAT [42][43][44][45][46][47], there is no specific review on BAT mass imaging. Therefore, in this systematic review, we have endeavored to identify the current imaging modalities that are independent of BAT activation state.…”