Diagnostic ultrasound ( PDFDrive )

CHAPTER 51 The Pediatric Liver and Spleen 1769
A
B
C
D
FIG. 51.38 Transplant Complications. (A) Thrombosis (cursors) of inferior vena cava (IVC) after bisegmental liver transplantation in a 2-year-old
child contrasts with the hypoechoic lumen of a nearby patent hepatic vein. (B) Partial thrombosis of oversewn donor IVC interposed between
native IVC and hepatic parenchyma. This is not usually problematic unless the clot propagates. (C) Color and pulsed Doppler image shows
arteriovenous istula with turbulent low in a transplant liver after biopsy. (D) Focal dilation (cursors) of a bile duct in the left lobe of the transplant
liver. This may be caused by hepatic arterial compromise and duct stenosis or ductal injury from previous percutaneous biopsy.
Continued
celiac and superior mesenteric arteries can create Doppler imaging
challenges. 97 Evaluation of the small bowel is limited when there
is postoperative ileus. Color Doppler evaluation of donor small
bowel wall perfusion is useful in the immediate perioperative
period. As bowel function returns, other clinical parameters
replace Doppler evaluation of bowel viability. When complications
arise, sonographic evaluation of the small bowel is similar to the
approach used for necrotizing enterocolitis, looking for pneumatosis,
poor perfusion, complicated ascites, and signs suggesting
perforation. Sonographic imaging experience with these patients
continues to expand.
THE SPLEEN
Examination of the spleen is an integral part of the sonographic
assessment of the child with liver or pancreatic disease or with
infection or trauma.
Cysts of the spleen are congenital (epithelial lined), 98 posttraumatic
(pseudocyst without lining), 99 or hydatid (unilocular
and later daughter cysts). 51 Splenic cysts associated with polycystic
kidney disease are rare in childhood. Splenic abscesses are found
most frequently in immunosuppressed or leukemic children with
candidiasis. he abscesses within the enlarged spleen usually
become visible long ater the diagnosis of Candida sepsis has
been made. Cat-scratch disease is another cause of multiple
splenic abscesses. Splenic calciications may be the result of
granulomatous infections (histoplasmosis, tuberculosis) or chronic
granulomatous disease of childhood.
Splenic enlargement accompanies many systemic infections,
including infectious mononucleosis and other viral infections,
typhoid fever, malaria, and fungal infections. Both the length
and the width of the spleen increase (Fig. 51.39). he lower
tip of the spleen becomes rounded. Other causes of enlargement
include congestion in portal hypertension and iniltration
with leukemic or lymphomatous tissue, which is usually
impossible to distinguish from normal splenic parenchyma
sonographically. hese conditions underline the importance
of examining the spleen in the context of the entire abdomen
(e.g., for liver disease and portosystemic collaterals or for
lymphadenopathy). 31