Learning objectives
This educational paper highlights:
- keypoints in hydatid disease ( HD) and in specialy in hepatic involvement ( HLD)
- the imaging techniques and imaging appearances of HLD and its complications
Background
Hydatid disease ( HD) is a zoonotic infection with endemic world-wide distribution,
is due to the larval stage of the tapeworm Echinococcus.( fig.1)
Humans may become intermediate hosts through contact with a definitive host (usually a domesticated dog) or ingestion of contaminated water or vegetables.
The parasite passes through the intestinal wall to reach the portal venous system or lymphatic system,
the liver acts as the first line of defense and is therefore the most frequently involved organ.
In humans,
hydatid disease involves the liver...
Findings and procedure details
Primarily affects the liver and typically demonstrates characteristic imaging findings.
Imaging findings depend on the stage of cyst growth (unilocular or contains daughter cysts,
partially or is completely calcified).
Several classification schemes based on cyst appearance have been proposed.The WHO developed a standardized classification system,originally developed by Gharbi and colleagues in 1981,
was revised by the WHO and is currently the screening method of choice.
( fig.3 and 5)
The diagnostic approach is summarized in figure 4.
Ultrasonography (US) is particularly useful for the detection...
Conclusion
Clinical presentations are nonspecific,
thus imaging plays an important role in diagnosis of HD.
Ultrasonography remains the most used diagnostic tool,
while computed tomography and MRI are essential for complicated HLD.
References
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