Echinococcosis ultrasound

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor-In-Chief: Mahshid Mir, M.D. [2] ; Cafer Zorkun, M.D., Ph.D. [3]; Kalsang Dolma, M.B.B.S.[4]

Overview

The imaging technique of choice for cystic echinococcosis is ultrasonography since it is not only able to visualize the cysts in the body’s organs but it is also inexpensive, non-invasive and gives instant results.^[1]^[2] Ultrasonography has been widely used for screening, clinical diagnosis, and monitoring of treatment of liver and intraabdominal cysts.

On ultrasound, cyst appears as a hyperechoic mass with a heterogeneity and contains scattered calcifications with irregular, poorly defined edges.
May show a double echogenic shadow due to the pericyst.
A central necroetic cavity with a hypoechoic pseudoliquid structure and anfractuous borders can also be demonstrated.
Multiseptate cyst with “daughter” cysts and echogenic material between cysts may be seen.
If the calcifications are associated with a positive result on specific serology, they may represent abortive forms of the disease.

Type of cyst	Status	Ultrasound features	Remarks
CL	Active	Unilocular, No cyst wall	Usually early stage Not fertile
CE1	Active	Cystic wall Hydatid sand	Fertile cyst
CE2	Active	Multivesicular, cyst wall, rosette-like	Fertile cyst
CE3	Transistional	Detached laminated membrane “Water lily” sign Decreased intracystic pressure	Beginning of degeneration May produce daughter cyst
CE4	Inactive	Heterogeneous hypoechogenic or hyperechogenic degenerative contents No daughter cyst	No living protoscolices
CE5	Inactive	Thick, calcified wall, calcification partial to Highly suggestive of diagnosis	No living protoscolices

Hepatic hydatid cyst

↑ Macpherson, Calum N.L., Ruth Milner, and . “Performance Characteristics and Quality Control of Community Based Ultrasound Surveys for Cystic and Alveolar Echinococcosis.” Acta Tropica 85. (2003): 203-09. Web. 24 February 2010.
↑ Brunetti, Enrico, Peter Kern , and Dominique Vuitton. “Expert Consensus for the Diagnosis and Treatment of Cystic and Alveolar Echinococcosis in Humans.” Acta Tropica (2009). Web. 24 February 2010.