Brown adipose tissue
Updates to Article Attributes
Brown adipose tissue (BAT) is one of two types of adipose tissue (white(the other one being white). It is important for producing heat energy (non-shivering thermogenesis) especially in the newborn, where it constitutes ~5% of body mass. It tends to disappear in adulthood. As a potential source of error on FDG-PET it is important to know for the radiologist and/or nuclear medicine physician.
Gross Anatomy
The principal sites of BAT are:
- neck
- supraclavicular fossa
- paravertebral tissue
- axilla
- mediastinum
-
abdomen
- para-aortic
- perihepatic
- paracolic
- suprarenal
- perinephric
Physiology, histology, innervation and brown). It containsblood supply
Compared to white fat, it contains smaller fat vacuoles, higher number of mitochondria and more vascularization than the white one. Moreover it is richly innervated by sympathetic nerves. Termogenin is a protein located on the mitochondrial membrane responsible for producing heat energy (non-shivering thermogenesis). BAT constitutes the 5% of body mass in newborns and tends to disappear in adulthood.
Epidemiology
Women present a gratergreater mass of BAT than men. It could be extremely stimulated by coldExtreme conditions such as cold temperature and by sympatheticstimulation of the sympathetic nervous system (i.e. higher levels of blood catecholamine in anxious patients) are known triggers.
The principal sites of BAT are:
Neck
Supraclavicular fossa
Paravertebral
Axilla
Mediastinum
Abdomen (para-aortic, perihepatic, para-colic, suprarenal, perinephric)
Practical points
BAT could be ais a dangerous potential source of false-positive FDG PET interpretations in oncologic imaging. 18F-FDG is highly accumulated in hypermetabolic BAT because glucose, even if not as a direct font of heat production but as a source of adenosine triphosphate, is required for heat production.
Because hypermetabolic BAT is typically bilateral and symmetric and corresponds at PET/CT images to fat areas, the appearance is rarely confused with malignancy. The acronym “USA-fat” (uptake in supraclavicular area fat) has been proposed to portray this typical appearance.However, when brown fat occurs in the mediastinum or in the abdomen, or near lymph-nodes or masses, the correct interpretation of focal FDG uptake can result in a real challenge. This is expecially true for Hodgkin Diseasedisease patients that are often young and where the disease is frequently located in the same regions of BAT main locations. Keeping the injection and waiting rooms at warmer temperatures may help to reduce BAT metabolism and therefore the FDG uptake. Premedication with benzodiazepine or propranolol has been proven to decrease brown fat activity.
-<p>Brown adipose tissue (BAT) is one of two types of adipose tissue (white and brown). It contains smaller fat vacuoles, higher number of mitochondria and more vascularization than the white one. Moreover it is richly innervated by sympathetic nerves. Termogenin is a protein located on the mitochondrial membrane responsible for producing heat energy (non-shivering thermogenesis). BAT constitutes the 5% of body mass in newborns and tends to disappear in adulthood. Women present a grater mass of BAT than men. It could be extremely stimulated by cold temperature and by sympathetic nervous system (i.e. higher levels of blood catecholamine in anxious patients).</p><p> </p><p>The principal sites of BAT are:</p><p><!--[if !supportLists]--> <!--[endif]-->Neck</p><p><!--[if !supportLists]--> <!--[endif]-->Supraclavicular fossa</p><p><!--[if !supportLists]--> <!--[endif]-->Paravertebral</p><p><!--[if !supportLists]--> <!--[endif]-->Axilla</p><p><!--[if !supportLists]--> <!--[endif]-->Mediastinum</p><p><!--[if !supportLists]--> <!--[endif]-->Abdomen (para-aortic, perihepatic, para-colic, suprarenal, perinephric)</p><p> </p><p>BAT could be a dangerous potential source of false-positive FDG PET interpretations in oncologic imaging. <sup>18</sup>F-FDG is highly accumulated in hypermetabolic BAT because glucose, even if not as a direct font of heat production but as a source of adenosine triphosphate, is required for heat production.</p><p>Because hypermetabolic BAT is typically bilateral and symmetric and corresponds at PET/CT images to fat areas, the appearance is rarely confused with malignancy. The acronym “USA-fat” (uptake in supraclavicular area fat) has been proposed to portray this typical appearance.<br>However, when brown fat occurs in the mediastinum or in the abdomen, or near lymph-nodes or masses, the correct interpretation of focal FDG uptake can result in a real challenge. This is expecially true for Hodgkin Disease patients that are often young and where the disease is frequently located in the same regions of BAT main locations. Keeping the injection and waiting rooms at warmer temperatures may help to reduce BAT metabolism and therefore the FDG uptake. Premedication with benzodiazepine or propranolol has been proven to decrease brown fat activity.</p>- +<p><strong>Brown adipose tissue</strong> (BAT) is one of two types of adipose tissue (the other one being white). It is important for producing heat energy (non-shivering thermogenesis) especially in the newborn, where it constitutes ~5% of body mass. It tends to disappear in adulthood. As a potential source of error on FDG-PET it is important to know for the radiologist and/or nuclear medicine physician.</p><p><strong>Gross Anatomy</strong></p><p>The principal sites of BAT are:</p><ul>
- +<li>neck</li>
- +<li>supraclavicular fossa</li>
- +<li>paravertebral tissue</li>
- +<li>axilla</li>
- +<li><a href="/articles/mediastinum">mediastinum</a></li>
- +<li>abdomen<ul>
- +<li>para-aortic</li>
- +<li>perihepatic</li>
- +<li>paracolic</li>
- +<li>suprarenal</li>
- +<li>perinephric</li>
- +</ul>
- +</li>
- +</ul><h5>Physiology, histology, innervation and blood supply</h5><p>Compared to white fat, it contains smaller fat vacuoles, higher number of mitochondria and more vascularization. Moreover it is richly innervated by sympathetic nerves. Termogenin is a protein located on the mitochondrial membrane responsible for producing heat energy. </p><h4>Epidemiology</h4><p>Women present a greater mass of BAT than men. Extreme conditions such as cold temperature and stimulation of the sympathetic nervous system (i.e. higher levels of blood catecholamine in anxious patients) are known triggers. </p><h4>
- +<!--[if !supportLists]-->Practical points</h4><p>BAT is a dangerous potential source of false-positive FDG PET interpretations in oncologic imaging. <sup>18</sup>F-FDG is highly accumulated in hypermetabolic BAT because glucose, even if not as a direct font of heat production but as a source of adenosine triphosphate, is required for heat production.</p><p>Because hypermetabolic BAT is typically bilateral and symmetric and corresponds at PET/CT images to fat areas, the appearance is rarely confused with malignancy. The acronym “USA-fat” (uptake in supraclavicular area fat) has been proposed to portray this typical appearance.<br>However, when brown fat occurs in the mediastinum or in the abdomen, or near lymph-nodes or masses, the correct interpretation of focal FDG uptake can result in a real challenge. This is expecially true for Hodgkin disease patients that are often young and where the disease is frequently located in the same regions of BAT main locations. Keeping the injection and waiting rooms at warmer temperatures may help to reduce BAT metabolism and therefore the FDG uptake. Premedication with benzodiazepine or propranolol has been proven to decrease brown fat activity.</p>
References changed:
- 2. Yeung HW, Grewal RK, Gonen M et-al. Patterns of (18)F-FDG uptake in adipose tissue and muscle: a potential source of false-positives for PET. J. Nucl. Med. 2003;44 (11): 1789-96. <a href="http://www.ncbi.nlm.nih.gov/pubmed/14602861">Pubmed citation</a><span class="auto"></span>
- 4. Truong MT, Erasmus JJ, Munden RF et-al. Focal FDG uptake in mediastinal brown fat mimicking malignancy: a potential pitfall resolved on PET/CT. AJR Am J Roentgenol. 2004;183 (4): 1127-32. <a href="http://dx.doi.org/10.2214/ajr.183.4.1831127">doi:10.2214/ajr.183.4.1831127</a> - <a href="http://www.ncbi.nlm.nih.gov/pubmed/15385319">Pubmed citation</a><span class="auto"></span>
- 1. Hany TF, Gharehpapagh E, Kamel EM et-al. Brown adipose tissue: a factor to consider in symmetrical tracer uptake in the neck and upper chest region. Eur. J. Nucl. Med. Mol. Imaging. 2002;29 (10): 1393-8. <a href="http://dx.doi.org/10.1007/s00259-002-0902-6">doi:10.1007/s00259-002-0902-6</a> - <a href="http://www.ncbi.nlm.nih.gov/pubmed/12271425">Pubmed citation</a><span class="auto"></span>
- 3. Agrawal A, Nair N, Baghel NS. A novel approach for reduction of brown fat uptake on FDG PET. Br J Radiol. 2009;82 (980): 626-31. <a href="http://dx.doi.org/10.1259/bjr/24661539">doi:10.1259/bjr/24661539</a> - <a href="http://www.ncbi.nlm.nih.gov/pubmed/19188245">Pubmed citation</a><span class="auto"></span>
- Yeung HW, Grewal RK, Gonen M, Schöder H, Larson SM. Patterns of (18)F-FDG uptake in adipose tissue and muscle: a potential source of false-positives for PET. J Nucl Med. 2003 Nov;44(11):1789-96.
- Truong MT, Erasmus JJ, Munden RF, Marom EM, Sabloff BS, Gladish GW, Podoloff DA, Macapinlac HA. AJR Am J Roentgenol. 2004 Oct;183(4):1127-32. Focal FDG uptake in mediastinal brown fat mimicking malignancy: a potential pitfall resolved on PET/CT.
- Hany TF, Gharehpapagh E, Kamel EM, Buck A, Himms-Hagen J, von Schulthess GK.Brown adipose tissue: a factor to consider in symmetrical tracer uptake in the neck and upper chest region. Eur J Nucl Med Mol Imaging. 2002 Oct;29(10):1393-8.
- Agrawal A, Nair N, Baghel NS. A novel approach for reduction of brown fat uptake on FDG PET.Br J Radiol. 2009 Aug;82(980):626-31.
Image 1 Nuclear medicine (axial CT, ax PET, ax fused images and coronal 3D MIP) ( update )
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