Diagnostic ultrasound ( PDFDrive )

104 PART II Abdominal and Pelvic Sonography
the portal venous radicles. he sonographic appearance is that
of a vascular mass connected to the portal system with turbulent
low.
Intrahepatic Portosystemic Venous Shunts
Intrahepatic arterial-portal istulas are well-recognized complications
of large-gauge percutaneous liver biopsy and trauma.
Conversely, intrahepatic portohepatic venous shunts are rare.
heir cause is controversial and believed to be either congenital
or related to portal hypertension. 114,115 Patients typically are middle
aged and present with hepatic encephalopathy. Anatomically,
portohepatic venous shunts are more common in the right lobe.
Sonography demonstrates a tortuous tubular vessel or complex
vascular channels, which connect a branch of the portal vein to
a hepatic vein or the IVC. 114-116 he diagnosis is conirmed
angiographically.
Aneurysm, Pseudoaneurysm,
and Dissection
he hepatic artery is the fourth most common site of an intraabdominal
aneurysm, following the infrarenal aorta, iliac, and
splenic arteries. Eighty percent of patients with a hepatic artery
aneurysm experience catastrophic rupture into the peritoneum,
biliary tree, gastrointestinal tract, or portal vein. 117 Hepatic artery
pseudoaneurysm secondary to chronic pancreatitis has been
described. he duplex Doppler sonographic examination revealed
turbulent arterial low within a sonolucent mass. 117 Primary
dissection of the hepatic artery is rare and in most cases leads
to death before diagnosis. 118 Sonography may show the intimal
lap with the true and false channels.
Hereditary Hemorrhagic Telangiectasia
Hereditary hemorrhagic telangiectasia, or Osler-Weber-Rendu,
is an autosomal dominant disorder that causes arteriovenous
(AV) malformations in the liver, hepatic ibrosis, and cirrhosis.
Patients present with multiple telangiectasias and recurrent
episodes of bleeding. Sonographic indings include a large feeding
common hepatic artery up to 10 mm, multiple dilated tubular
structures representing AV malformations, and large draining
hepatic veins secondary to AV shunting. 119
Peliosis Hepatis
Peliosis hepatis is a rare liver disorder characterized by blood-illed
cavities ranging from less than a millimeter to many centimeters
in diameter. It can be distinguished from hemangioma by the
presence of portal tracts within the ibrous stroma of the blood
spaces. he pathogenesis of peliosis hepatis involves rupture of
the reticulin ibers that support the sinusoidal walls, secondary
to cell injury or nonspeciic hepatocellular necrosis. he diagnosis
of peliosis can be made with certainty only by histologic examination.
Most cases of peliosis afect the liver, although other solid
internal organs and lymph nodes may be involved in the process
as well.
Although early reports described incidental detection of
peliosis hepatis at autopsy in patients with chronic wasting
disorders, it has now been seen following renal and liver transplantation,
in association with a multitude of drugs, especially
anabolic steroids, and with an increased incidence in patients
with HIV. 119 he HIV association may occur alone or as part of
bacillary angiomatosis in the spectrum of opportunistic infections
of AIDS. 120 Peliosis hepatis has the potential to be aggressive
and lethal.
he imaging features of peliosis hepatis have been described
in single case reports, 121-123 although oten without adequate
histologic conirmation. Angiographically, the peliotic lesions
have been described as accumulations of contrast detected
late in the arterial phase and becoming more distinct in the
parenchymal phase. 124 On sonography, described lesions are
nonspeciic and have shown single or multiple masses of heterogeneous
echogenicity. 119,120,125 Calciications have been reported 125
(Fig. 4.40). Peliosis hepatis is diicult to diagnose both clinically
and radiologically and must be suspected in a susceptible
individual with a liver mass.
A
B
FIG. 4.40 Peliosis Hepatis. Peliosis hepatis in 34-year-old woman with deteriorating liver function necessitating transplantation. (A) Sagittal
right lobe and (B) sagittal left lobe scans show multiple large liver masses with innumerable tiny punctate calciications. (With permission from
Muradali D, Wilson SR, Wanless IR, et al. Peliosis hepatis with intrahepatic calciications. J Ultrasound Med. 1996;15[3]:257-260. 125 )