Diagnosis
Fatty Degeneration of Hydatid cyst
Radiological Findings, Disease course, and Management
Ultrasound Liver
Findings
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A well defined anechoic cystic lesion with imperceptible wall and focal wall irregularities along the medial wall in the right lobe of the liver
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No internal echoes/calcifications
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CT
Findings
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well defined hypodense cystic lesion in the right lobe of liver with imperceptible walls and thin enhancing internal septations.
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Few scattered fat densities within the cyst
MRI
Findings
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well defined hypointense cyst wall
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Better defined daughter cyst
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Presence of fat confirmed
Impression
Fatty degeneration of hydatid cyst
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Discussion
Background
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Fat within a Hepatic Hydatid Cyst has only rarely been described in the literature
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Fat within a Hydatid Cyst is seen as fat-fluid levels or as globules of fat
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It is related to degeneration of hydatid membranes
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Increasing cholesterol in cyst fluid has been associated with maturation and degeneration, therefore, development of fatty attenuation seems to be related to the ageing process of the cyst
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Fat-fluid levels within a HHC detected on imaging studies favour the presence of a biliary communication and, in most patients, such a communication can be demonstrated on imaging. However, small globules of lipid / fat within a HHC can be explained by degeneration of the hydatid membranes as part of the ageing process of the HHC
Conclusion
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Fat within HHCs is a rare finding
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can be attributed to communication of the cyst with the biliary tree or to the process of degeneration of the hydatid membranes due to ageing of the cyst
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fat within HHCs, although rare, can occur
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presence of a fat-fluid level within a HHC should lead to a search for a biliocystic communication, whereas the presence of small globules of fat needs not indicate a communication with the biliary tree and can be explained by degeneration of hydatid membranes as a part of ageing of the hydatid cyst.
References
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Tandon, A. S., & Saxena, D. (2014). Fat within Hepatic Hydatid Cysts: a Report of Three Cases. Retrieved from www.hkjr.org/system/files/v17n3_ 198Fat.pdf
Case 9
Contributors
Dr. Ambika Sunil Gayad