Diagnostic ultrasound ( PDFDrive )

CHAPTER
8
The Gastrointestinal Tract
Stephanie R. Wilson
SUMMARY OF KEY POINTS
• High-resolution ultrasound allows for excellent depiction of
the bowel, including the normal multilayered appearance of
the bowel wall and many pathologic features.
• Ultrasound is a safe, objective, and accurate method for
measuring the severity of inlammatory activity in
inlammatory bowel disease, an essential requirement
considering the young population most often affected by
this chronic and often debilitating disease.
• Contrast-enhanced ultrasound is an objective biomarker
that may accurately evaluate disease activity in those with
bowel wall inlammation.
• Elastography measures bowel wall stiffness, increasing in
those with chronic disease, helping to differentiate
patients amenable to medical therapy from those requiring
surgical intervention.
• Transrectal ultrasound (TRUS) is an excellent noninvasive
and well-tolerated procedure for staging of rectal
tumors.
• Transvaginal ultrasound increases accuracy of bowel
ultrasound in many women as pathologic features
located deep in the pelvis may only be visible with this
technique.
• Transperineal scan allows for accurate depiction of perianal
inlammatory masses without necessity of performing
often painful scans with endoanal or endorectal placement
of the transducer.
CHAPTER OUTLINE
ANATOMY AND SONOGRAPHIC
TECHNIQUE
The Gut Signature
Gut Wall Pathology
Imaging Technique
Doppler Evaluation of Gut Wall
Contrast-Enhanced Ultrasound and
Elastography of the Bowel
GASTROINTESTINAL TRACT
NEOPLASMS
Adenocarcinoma
Gastrointestinal Stromal Tumors
Lymphoma
Metastases
INFLAMMATORY BOWEL DISEASE:
CROHN DISEASE
Classic Features
Gut Wall Thickening
Inlammatory Fat
Lymphadenopathy
Hyperemia
Mucosal Abnormalities
Conglomerate Masses
Gastrointestinal (GI) tract sonography is frequently frustrating
and always challenging. Gas content within the gut lumen
can make visibility diicult or even impossible; intraluminal
luid may mimic cystic masses; and fecal material can create a
variety of artifacts and pseudotumors. Nevertheless, normal gut
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COMPLICATIONS
Strictures
Incomplete Mechanical Bowel
Obstruction
Localized Perforation
Inlammatory Masses
Fistula Formation
Perianal Inlammatory Disease
ACUTE ABDOMEN
Right Lower Quadrant Pain
Acute Appendicitis
Crohn Appendicitis
Right-Sided Diverticulitis
Acute Typhlitis
Mesenteric Adenitis With Terminal
Ileitis
Right-Sided Segmental Omental
Infarction
Left Lower Quadrant Pain
Acute Diverticulitis
OTHER ABNORMALITIES
Mechanical Bowel Obstruction
Paralytic Ileus
Gut Edema
Gastrointestinal Tract Infections
AIDS Patients
Pseudomembranous Colitis
Congenital Cysts
Ischemic Bowel Disease
Pneumatosis Intestinalis
Mucocele of Appendix
Gastrointestinal Tract Hematoma
Peptic Ulcer
Bezoars
Intraluminal Foreign Bodies
Celiac Disease
Cystic Fibrosis
ENDOSONOGRAPHY
Upper Gastrointestinal Tract
Rectum: Tumor Staging of Rectal
Carcinoma
Anal Canal
Fecal Incontinence
Perianal Inlammatory Disease
Acknowledgment
has a reproducible pattern, or gut signature, and a variety of gut
diseases create recognizable sonographic abnormalities. herefore
ultrasound may play a valuable role in the evaluation of patients
in a variety of clinical situations, including suspicion of acute
conditions of the GI tract, especially appendicitis and diverticulitis.