Diagnostic ultrasound ( PDFDrive )

102 PART II Abdominal and Pelvic Sonography
A
B
C
D
FIG. 4.38 Budd-Chiari Syndrome. (A) Gray-scale transverse image of hepatic venous conluence shows complete absence of the right hepatic
vein with obliteration of the lumen of a common trunk for the middle and left hepatic veins. (B) Color Doppler image shows that blood low in the
middle hepatic vein (blue) is normally directed toward the inferior vena cava. As the trunk is obliterated, all the blood is lowing out of the left
hepatic vein (red), which is abnormal. Other images showed anastomoses of the left hepatic vein with surface collaterals. (C) Color Doppler image
shows an anomalous left hepatic vein with low to the inferior vena cava (normal direction) and aliasing from a long stricture. (D) Spectral Doppler
waveform of the anomalous left hepatic vein shows a very high abnormal velocity of approximately 140 cm/sec, conirming the tight stricture.
tubular vascular structures in an abnormal location and typically
are seen extending from a hepatic vein to the liver surface, where
they anastomose with systemic capsular vessels.
Duplex Doppler ultrasound and color Doppler low imaging
(CDFI) can help determine both the presence and the direction
of hepatic venous low in the evaluation of patients with suspected
Budd-Chiari syndrome. he middle and let hepatic veins are
best scanned in the transverse plane at the level of the xiphoid
process. he right hepatic vein is best evaluated from a right
intercostal approach. 105 he intricate pathways of blood low out
of the liver in the patient with Budd-Chiari syndrome can be
mapped with documentation of hepatic venous occlusions,
hepatic-systemic collaterals, hepatic venous–portal venous collaterals,
and increased caliber of anomalous or accessory hepatic
veins.
he normal blood low in the IVC and hepatic veins is phasic
in response to both the cardiac and respiratory cycles. 100 In
Budd-Chiari syndrome, low in the IVC, hepatic veins, or both,
changes from phasic to absent, reversed, turbulent, or continuous.
104,112 Continuous low has been called the pseudoportal
Doppler signal and appears to relect either partial IVC obstruction
or extrinsic IVC compression. 103 he portal blood low also
may be afected and is characteristically either slowed or
reversed. 104