Diagnostic ultrasound ( PDFDrive )

CHAPTER 51 The Pediatric Liver and Spleen 1763
A
B
C
D
FIG. 51.33 Budd-Chiari Syndrome. (A) Acute appearance: the liver is enlarged, surrounded by ascitic luid. (B) The diagonal course of a
hepatic vein is illed with echogenic clot. (C) Longitudinal image of the inferior vena cava shows abrupt truncation and lack of intrahepatic low.
(D) Thrombus at the hepatic venous conluence (arrows) was conirmed with magnetic resonance low-sensitive imaging.
the major hepatic veins, or the IVC near the hepatic vein ostia. 80
Small-vessel hepatic venous occlusive disease (VOD), also
known as sinusoidal obstruction syndrome (SOS), is caused
by toxins (pyrrolizidine alkaloids contained in ragwort or Jamaican
bush tea); chemotherapy; bone marrow and stem cell transplantation;
lupus erythematosus; hepatic irradiation; and oral contraceptives.
his VOD involves primarily small hepatic venous radicles,
although the major branches may be secondarily involved.
Sonographic indings of VOD include splenomegaly, ascites,
small-caliber hepatic veins, and low in paraumbilical veins. he
sonographic diagnosis of VOD remains diicult; clinical and
laboratory criteria are better indicators of the severity of VOD
and its response to medical therapy. 81 hrombosis of the main
hepatic veins is usually caused by coagulation abnormalities or
congenital malformations of the hepatic vein ostia. Obstruction
of the hepatic portion of the IVC may result in thrombosis of
the hepatic veins. Congenital membranes of the IVC resulting
from faulty embryologic fenestration of its lumen can also lead
to obstruction of hepatic veins. 82,83 he most common position
for such a membrane is below an obstructed let hepatic vein
and above a patent right hepatic vein, probably a result of an
obstructing ibrous remnant of the let umbilical vein and ductus
venosus.
Causes of Hepatic Venous Occlusive Disease
Toxins
Pyrrolizidine alkaloid
Ragwort or Jamaican bush tea
Chemotherapy
Bone marrow transplantation
Lupus erythematosus
Hepatic irradiation
Oral contraceptives
Coagulation abnormalities
Congenital malformations of hepatic vein ostia
Obstruction of hepatic portion of inferior vena cava
Congenital membranes of inferior vena cava