Diagnostic ultrasound ( PDFDrive )

CHAPTER 8 The Gastrointestinal Tract 277
A
B
C
D
FIG. 8.22 Localized Perforation With Phlegmon. Two young women with acute lare of Crohn disease symptoms. (A) and (B) First patient.
(A) Cross-sectional and (B) long-axis images of the bowel show wall thickening and a deep hypoechoic mass with ingerlike projections into the
surrounding perienteric fat, suggesting phlegmon. Also, on (A), air appears as a bright focus extending beyond the lumen of the bowel into the
bowel wall, suggesting localized perforation. (C) and (D) Second patient. (C) Cross-sectional image of the ileum shows a large area of disruption
of the bowel wall, an adjacent hypoechoic phlegmon, and an air tract from localized perforation. (D) Long-axis image of loop of ileum shows that
the wall is uniformly thickened with layer preservation. The phlegmon is on the margin of the bowel and not shown in the longitudinal view. See
also Video 8.11.
ACUTE ABDOMEN
Sonography is a valuable imaging tool in patients with speciic
suspected acute GI abnormalities such as acute appendicitis or
acute diverticulitis. 38 However, its contribution to the assessment
of patients with possible GI tract disease is less certain.
Seibert et al. 39 emphasized the value of ultrasound in assessing
the patient with a distended and gasless abdomen and detecting
ascites, unsuspected masses, and abnormally dilated, luid-illed
loops of small bowel. In my experience, sonography has been
helpful not only in the gasless abdomen but also in a variety
of other situations. he real-time aspect of sonographic study
allows for direct patient–sonographer/physician interaction, with
conirmation of palpable masses and focal points of tenderness.
he doctrine “scan where it hurts” is invaluable and has led
sonographers to describe the value of the sonographic equivalent
to clinical examination with such descriptors as a sonographic
Murphy sign or sonographic McBurney sign. Similar to the
radiographic approach to plain ilm interpretation, a systematic
approach is essential in the sonographic assessment of the
abdomen in a patient with an acute abdomen of uncertain
origin.
he abdominal ultrasound evaluation should include visible gas
and luid (to determine their luminal or extraluminal location),
the perienteric sot tissues, and the GI tract itself. Identiication
of gas in a location where it is not usually found is a clue
to many important diagnoses. he gas itself may appear as a
bright, echogenic focus, but the identiication of the artifacts
associated with the gas pockets usually leads to their detection.
hese include both ring-down artifact and “dirty” shadowing.
Extraluminal gas may be intraperitoneal (Free intraperitoneal