Diagnostic ultrasound ( PDFDrive )

CHAPTER 5 The Spleen 147
A
B
C
D
FIG. 5.9 Varices in Patients With Portal Hypertension. (A) Coronal gray-scale and (B) power Doppler images show splenomegaly and tortuous
varices medial to the spleen. (C) and (D) Varices medial and inferior to the spleen representing a splenorenal shunt.
complex, with wall calciications and internal echoes (Fig. 5.11B).
However, diferentiation between both types of cysts is usually
not possible because there is considerable overlap both on imaging
and on pathologic examination 34 (Fig. 5.11C). Furthermore, a
history of signiicant trauma or infection is rarely established in
patients with a pseudocyst. Both types of cysts can be complex,
with wall calciications or increased echogenicity of the luid
caused by cholesterol crystals, inlammatory debris, or hemorrhage
35 (Fig. 5.12; see also Fig. 5.10).
Hydatid (or echinococcal) disease is the most common cause
of splenic cysts in endemic areas. Isolated splenic involvement
without liver and peritoneal disease is rare. 36 he appearance of
a hydatid cyst depends on the stage of the disease and varies
from simple to complex, with or without daughter cysts (Fig.
5.13). he diagnosis is made by combining the appropriate history,
geographic background, serologic testing, and imaging appearances.
37,38 Percutaneous ine-needle aspiration can be diagnostic,
provided the pathologist has been alerted to search for the
scolices.
Pseudocysts related to pancreatitis in or adjacent to the spleen
are usually diagnosed by the associated features of pancreatitis. 39
Splenic peliosis is very rare and characterized by multiple
blood-illed cystic spaces, sometimes involving the entire spleen. 40
On ultrasound, these lesions appear as multiple indistinct
hypoechoic lesions. he lesions may be hyperechoic if thrombosis
is present.