Phrygian cap

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Disclosures - updated 16 Jan 2024:

Integral Diagnostics, Shareholder (ongoing)
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Phrygian caps are the most common congenital anatomic variant of the gallbladder. It It denotes folding of the fundus back upon the gallbladder body and is asymptomatic with no pathological significance.

Radiographic findings

A Phrygian cap may be identified on ultrasound, multiphase CT/MRI, or cholescintigraphy³.

Ultrasound

May be wrongly interpreted as a septum in an otherwise normal gallbladder.

CT/MRI

Multiphase CT/MRI usually clearly differentiates Phrygian caps from mass lesions.

Nuclear medicine

Cholescintigraphy

When multiphase CT/MRI is inconclusive, cholescintigraphy may be critical in preventing an unnecessary cholecystectomy. The gallbladder often appears smaller than the gallbladder fossa. Delayed imaging demonstrates filling of the gallbladder, which rules out an underlying mass lesion.

Treatment and prognosis

As a benign anatomical variant, Phrygian caps should not be mistaken for a pathology and does not require treatment.

History and etymology

The appearance is reminiscent of a Phrygian cap, a a head garment worn by inhabitants of Phrygia (modern Turkey) 1200-700 BCE ^1,2. Of note, the Smurfs ~~also~~ also wear a similar hat.

Differential diagnosis

gallbladder septum
adenomyomatosis(annular variant)

-<p><strong>Phrygian caps</strong> are the most common congenital <a href="/articles/anatomical-variants">anatomic variant</a> of the <a href="/articles/gallbladder">gallbladder</a>. It denotes folding of the fundus back upon the gallbladder body and is asymptomatic with no pathological significance.</p><h4>Radiographic findings</h4><p>A Phrygian cap may be identified on ultrasound, multiphase CT/MRI, or <a href="/articles/cholescintigraphy">cholescintigraphy</a> <sup>3</sup>. </p><h5>Ultrasound </h5><p>May be wrongly interpreted as a <a href="/articles/septate-gallbladder">septum</a> in an otherwise normal gallbladder.</p><h5>CT/MRI</h5><p>Multiphase CT/MRI usually clearly differentiates Phrygian caps from mass lesions. </p><h5>Nuclear medicine</h5><h6>Cholescintigraphy</h6><p>When multiphase CT/MRI is inconclusive, <a href="/articles/cholescintigraphy">cholescintigraphy</a> may be critical in preventing an unnecessary <a href="/articles/cholecystectomy-1">cholecystectomy</a>. The gallbladder often appears smaller than the gallbladder fossa. Delayed imaging demonstrates filling of the gallbladder, which rules out an underlying mass lesion. </p><h4>Treatment and prognosis</h4><p>As a <a href="/articles/anatomical-variants">benign anatomical variant</a>, Phrygian caps should not be mistaken for a pathology and does not require treatment.</p><h4>History and etymology</h4><p>The appearance is reminiscent of a <a href="http://en.wikipedia.org/wiki/Phrygian_cap">Phrygian cap</a>, a head garment worn by inhabitants of Phrygia (modern Turkey) 1200-700 BCE <sup>1,2</sup>. Of note, the <a href="http://en.wikipedia.org/wiki/The_Smurfs">Smurfs</a> also wear a similar hat. </p><h4>Differential diagnosis</h4><ul>
~~-<li><a href="/articles/septate-gallbladder">gallbladder septum</a></li>~~
~~-<li>~~
~~-<a href="/articles/adenomyomatosis-of-the-gallbladder">adenomyomatosis</a> (annular variant)</li>~~
+<p><strong>Phrygian caps</strong> are the most common congenital <a href="/articles/anatomical-variants">anatomic variant</a> of the <a href="/articles/gallbladder">gallbladder</a>. It denotes folding of the fundus back upon the gallbladder body and is asymptomatic with no pathological significance.</p><h4>Radiographic findings</h4><p>A Phrygian cap may be identified on ultrasound, multiphase CT/MRI, or <a href="/articles/cholescintigraphy">cholescintigraphy</a> <sup>3</sup>. </p><h5>Ultrasound </h5><p>May be wrongly interpreted as a <a href="/articles/septate-gallbladder">septum</a> in an otherwise normal gallbladder.</p><h5>CT/MRI</h5><p>Multiphase CT/MRI usually clearly differentiates Phrygian caps from mass lesions. </p><h5>Nuclear medicine</h5><h6>Cholescintigraphy</h6><p>When multiphase CT/MRI is inconclusive, <a href="/articles/cholescintigraphy">cholescintigraphy</a> may be critical in preventing an unnecessary <a href="/articles/cholecystectomy-1">cholecystectomy</a>. The gallbladder often appears smaller than the gallbladder fossa. Delayed imaging demonstrates filling of the gallbladder, which rules out an underlying mass lesion. </p><h4>Treatment and prognosis</h4><p>As a <a href="/articles/anatomical-variants">benign anatomical variant</a>, Phrygian caps should not be mistaken for a pathology and does not require treatment.</p><h4>History and etymology</h4><p>The appearance is reminiscent of a Phrygian cap, a head garment worn by inhabitants of Phrygia (modern Turkey) 1200-700 BCE <sup>1,2</sup>. Of note, the Smurfs also wear a similar hat. </p><h4>Differential diagnosis</h4><ul>
+<li><p><a href="/articles/septate-gallbladder">gallbladder septum</a></p></li>
+<li><p><a href="/articles/adenomyomatosis-of-the-gallbladder">adenomyomatosis</a> (annular variant)</p></li>

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