Ultrasound images of liver Amebic Abscess
Amebiasis caused by the parasite Entamoeba histolytica is an endemic disease of tropical areas, such as Mexico, Central and South America, Africa and Asia. Amebic liver abscess develops after infestation of colonic mucosa by the parasites,which lodge in the portal system. The liver can be invaded in one of three ways:
• via the portal vein (most common),
• through lymphatics,
• via direct extension through the colon wall into
the peritoneum and then through the liver capsule. Amebic liver abscess is the most common extraintestinal manifestation. Most patients with amebic liver abscesses present with a tender liver and abdominal pain in the right upper quadrant. Amebae are not usually found in the stool of patients with an amebic liver abscess. Because the clinical features and findings of stool examinations for amebae are usually not specific or are negative, serologic tests are helpful in detecting suspected amebic abscess; such tests are positive in about 90% of patients.
On US studies, amebic abscesses are usually large, round, sharply-defined, hypoechoic masses with fine, low-level internal echoes at high gain settings The CT appearance of amebic abscess is nonspecific.
and variable; the lesion is usually round or oval and demonstrates peripheral hypodensity. A slightly hyperdense peripheral rim can be seen on unenhanced scans,which generally shows marked enhancement after administration of contrast material.
Lesions may appear as unilocular or multilocular masses, with internal debris and nodularity of the margins.
ultrasound images of Amebic abscess on US. The ultrasound scan reveals two large lesions (arrows) with different echogenicity
GB polyp
BalasHapus