Diagnostic ultrasound ( PDFDrive )

CHAPTER
53
The Pediatric Gastrointestinal Tract
Susan D. John and Martha Mappus Munden
SUMMARY OF KEY POINTS
• Successful bowel ultrasound is facilitated by use of
high-frequency transducers and real-time viewing of the
bowel activity. Oral luid administration and graded
compression techniques help displace interfering bowel
gas.
• Accurate measurement of the pyloric muscle thickness
with adequate distention of the stomach with luid is the
key to correct diagnosis of hypertrophic pyloric stenosis.
When the pylorus is normal, the duodenum should be
examined, as well as the mesenteric vessels.
• The diagnosis of ileocolic intussusception can be made with
ultrasound with a high degree of accuracy, precluding the
need for a diagnostic enema when normal. Transient small
bowel intussusceptions are common, have a different
appearance on ultrasonography, and do not require
treatment or follow-up unless very long or persistent.
• Inlammatory conditions of the small and large intestine
can be easily evaluated with ultrasound. Speciic features
such as mucosal or transmural edema, echogenicity, and
blood low assessment with Doppler imaging can help to
narrow the range of differential diagnoses and can be used
to monitor therapy.
• Ultrasound indings of bowel wall thickening and
pneumatosis intestinalis can help make the diagnosis of
necrotizing enterocolitis when not evident on radiographs.
Complex luid in the abdomen helps to diagnose
perforation in infants with a gasless abdomen.
• Ultrasound is the procedure of choice for the initial
evaluation of the child with acute abdominal pain.
Appendicitis can be detected in the majority of children
with experience and proper technique. Secondary indings
such as absent bowel peristalsis, mesenteric edema, and
free or loculated luid collections can help make the
diagnosis of appendicitis, even when the appendix itself is
not visible.
• Cystic abdominal masses are well seen with ultrasound
and may be associated with the gastrointestinal tract. Wall
characteristics and presence of internal septations, debris,
calciications, or fat can help to determine the etiology of
the mass.
• Ultrasound of the pancreas in children is most helpful for
identifying peripancreatic luid collections or pseudocysts
resulting from pancreatitis and detecting cystic pancreatic
masses.
CHAPTER OUTLINE
ESOPHAGUS AND STOMACH
Normal Anatomy and Technique
Esophagus
Stomach
Hypertrophic Pyloric Stenosis
Pylorospasm and Minimal Muscular
Hypertrophy
Pitfalls in Sonographic Diagnosis
Gastric Diaphragm
Gastritis and Ulcer Disease
Bezoar
DUODENUM AND SMALL BOWEL
Normal Anatomy and Technique
Congenital Duodenal Obstruction
Duodenal Hematoma
Small Bowel Obstruction
Intussusception
COLON
Normal Anatomy and Technique
Ectopic or Imperforate Anus
INTESTINAL INFLAMMATORY
DISEASE
Appendicitis
Gastrointestinal Neoplasms and Cysts
PANCREAS
Normal Anatomy and Technique
Pancreatitis
Pancreatic Masses
ESOPHAGUS AND STOMACH
Normal Anatomy and Technique
Sonography has become an important diagnostic imaging modality
in the evaluation of the gastrointestinal (GI) tract of children.
Ultrasound permits direct visualization of the various mural
layers of the GI tract. he ability to observe GI dynamics without
exposure to ionizing radiation is an added asset of sonography.
Video clips made during scanning can be a valuable resource to
view peristalsis and to capture subtle abnormalities in mobile
children. Ultrasound is most suitable for portions of the GI tract
that are not surrounded by or illed with large amounts of gas.
he stomach is best evaluated ater allowing the patient to ingest
clear luids. Sugar water works well for infants.
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