Riedel lobe
Updates to Article Attributes
Riedel lobe is a common anatomical variant of the liver to be aware of because it can simulate a mass.
Its misidentification as a pathologic abdominal mass has led to surgery. Pathology can also occur within it (e.g. malignancy or even torsion) and cause atypical hepatic symptoms low in the pelvis 1,2.
Some feel that the term Riedel lobe should be abandoned as it is not an accessory lobe but just a variant of the appearance of the right lobe.
Epidemiology
Riedel lobe has an incidence of ~17.5% (range 3.3-31%) and is more frequently found in females (M:F = 1:3) 2,3.
Gross anatomy
Riedel lobe is a tongue-like, inferior projection of the right lobe of the liver beyond the level of the most inferior costal cartilage on cross-sectional images 1. It is not considered a true accessory lobe of the liver but an anatomical variant of the right lobe of the liver 3.
Differential diagnosis
History and etymology
It was originally reported in 1888 by the German surgeon, Bernhard Moritz Carl Ludwig Riedel (German Surgeon, 1849(1849-1916) 4 in seven female patients who had palpable masses in the right hypochondrium, which were subsequently confirmed at surgery 2.
-<p><strong>Riedel lobe </strong>is a common anatomical variant of the <a href="/articles/liver">liver</a> to be aware of because it can simulate a mass.</p><p>Its misidentification as a pathologic abdominal mass has led to surgery. Pathology can also occur within it (e.g. malignancy or even torsion) and cause atypical hepatic symptoms low in the pelvis <sup>1,2</sup>.</p><h4>Epidemiology</h4><p>Riedel lobe has an incidence of ~17.5% (range 3.3-31%) and is more frequently found in females (M:F = 1:3) <sup>2,3</sup>.</p><h4>Gross anatomy</h4><p>Riedel lobe is a tongue-like, inferior projection of the right lobe of the <a href="/articles/liver">liver</a> beyond the level of the most inferior <a href="/articles/costal-cartilage">costal cartilage</a> on cross-sectional images <sup>1</sup>. It is not considered a true accessory lobe of the liver but an anatomical variant of the right lobe of the <a href="/articles/liver">liver</a> <sup>3</sup>.</p><h4>Differential diagnosis</h4><ul><li><a href="/articles/hepatomegaly">hepatomegaly</a></li></ul><h4>History and etymology</h4><p>It was originally reported in 1888 by <strong>Bernhard Moritz Carl Ludwig Riedel</strong> (German Surgeon, 1849-1916) <sup>4</sup> in seven female patients who had palpable masses in the right hypochondrium, which were subsequently confirmed at surgery <sup>2</sup>. </p>- +<p><strong>Riedel lobe </strong>is a common <a title="Anatomical variants" href="/articles/anatomical-variants">anatomical variant</a> of the <a href="/articles/liver">liver</a> to be aware of because it can simulate a mass.</p><p>Its misidentification as a pathologic abdominal mass has led to surgery. Pathology can also occur within it (e.g. malignancy or even torsion) and cause atypical hepatic symptoms low in the pelvis <sup>1,2</sup>.</p><p>Some feel that the term Riedel lobe should be abandoned as it is not an accessory lobe but just a variant of the appearance of the right lobe.</p><h4>Epidemiology</h4><p>Riedel lobe has an incidence of ~17.5% (range 3.3-31%) and is more frequently found in females (M:F = 1:3) <sup>2,3</sup>.</p><h4>Gross anatomy</h4><p>Riedel lobe is a tongue-like, inferior projection of the right lobe of the liver beyond the level of the most inferior <a href="/articles/costal-cartilage">costal cartilage</a> on cross-sectional images <sup>1</sup>. It is not considered a true accessory lobe of the liver but an anatomical variant of the right lobe of the <a href="/articles/liver">liver</a> <sup>3</sup>.</p><h4>Differential diagnosis</h4><ul><li><a href="/articles/hepatomegaly">hepatomegaly</a></li></ul><h4>History and etymology</h4><p>It was originally reported in 1888 by the German surgeon, <strong>Bernhard Moritz Carl Ludwig Riedel</strong> (1849-1916) <sup>4</sup> in seven female patients who had palpable masses in the right hypochondrium, which were subsequently confirmed at surgery <sup>2</sup>. </p>