9%20ECOGRAFIA%20ABDOMINAL%20COMO%20CUANDO%20DONDE

THE PAEDIATRIC ABDOMEN 239
E
F
G
Figure 9.17 cont’d (E) Increased vascularity of inflamed appendix seen on colour flow Doppler imaging. (F) Walled
off appendix abscess containing fluid and gas. (G) Complex inflammatory mass containing appendicolith.
Ultrasound demonstrates a hypoechoic, thickened
appendix, > 6 mm thick, with a blind end (Fig.
9.17). Occasionally an appendicolith, with strong
acoustic shadowing, is present. The inflamed appendix
is not compressible on gentle, graded compression
with the transducer. This should be done very
carefully, and released very slowly to avoid rebound
tenderness. Ultrasound cannot reliably exclude
appendicitis, especially if the appendix is retrocaecal.
Perforation may not be easy to see with ultrasound,
as fluid may disperse through the abdomen
with decompression of the appendix itself.
However, a frank periappendiceal fluid collection
or abscess is easily demonstrable in a proportion of
children and may, in some cases, be treated conservatively
with antibiotics or drained percutaneously
prior to surgery. The presence of free fluid, particularly
if clear, in the abdomen is a non-specific
finding and is not a reliable indicator of an acute
abdomen. If echogenic fluid is seen, this is suggestive
of intraperitoneal infection in the child with
acute abdominal pain, but may be seen in other
conditions, for example rupture of a haemorrhagic
ovarian cyst. If ultrasound is equivocal, the clinicians
may decide to observe the child but further
imaging with CT scanning can be helpful in a few
selective cases. Alternatively a laparoscopic examination
may be performed where there is significant
clinical concern 37 .
Enteric duplication cysts
These comparatively rare lesions present in infancy or
early childhood with nausea, gastrointestinal bleeding,
intestinal obstruction and, occasionally, a palpable
mass. Most are intra-abdominal but oesophageal