1. WFUMB
World Federation for Ultrasound
in Medicine & Biology
1
Maria Cristina Chammas
Vice-President 2 of WFUMB (2017-19)
Hospital das Clínicas - School of Medicine -
São Paulo University - Brazil
DASA Group SP – Brazil
3. 1. Introduction
2. Exam key points
3. Acute pain: main causes
according abdominal region
Causes can be divided:
Non traumatic (vascular, inflammatory,
hemorrhagic, obstructive, perforating)
Traumatic
Objectives
4. • 4- 5% of patients in the ER are due to acute abdominal pain
• Medical history + physical examination
• Clinical evaluation
• Laboratory invetigations
• Most common causes: cholycistitis, appendicitis, bowel
obstruction. (*Others: diverticulitis, apendagitis).
• Less frequent: perforated viscus, bowel ischemia (CT)
• DD: renal colic, ectopic pregnancy, pancreatitis, etc
IMAGING PLAYS AN IMPORTANT ROLE US!
INTRODUCTION
Clinicians will consider
imaging exams
Stocker et al. Radiology 2009; 253(1):31-46
5. US advantages:
• widely available, easily accessible in the ER
• real time dynamic examination (peristalsis, blood flow),
graded-compression maneuvers (= gradual compression)
• to correlate imaging with point of the maximum pain
• Lower cost (x CT), accurate, safe, without radiation (x CT)
• US, the first imaging modality to evaluate the acute
abdomen, in general, when not, adds information to X-Rays,
CT, etc
• US findings modifies the treatment in 22% of cases
INTRODUCTION
Acute abdominal pain
Stocker et al. Radiology 2009; 253(1):31-46
6. KEY POINTS
Question: where is the pain point?
Start exam: 3.5 – 5.0 MHz probe.
Change to higher frequency probe depending on the pain
region
Transvaginal US: helpful in demonstrating gynecological
conditions, diverticulitis, inflamed appendix in lower position,
etc
3.5 MHz probe
8. US LAYERS
1. WHITE - mucosa
2. BLACK - muscularis mucosa
3. WHITE - submucosa
4. BLACK - muscularis propria
5. WHITE - serosa
KEY POINTS: GUT SIGNATURE
Layers: interface
more than true
histological layers
9. • On high resolution images, nl bowel wall is 3-4 mm
• Wall and layers abnormalities, US can assess:
Length of disease segments
Size of thickening
Abnormal echogenicity
Loss of stratification
Symmetry
Ulcerations
Distribuition of the lesions
Bowel stiffness
Presence of strictures
Bowel distension
KEY POINTS
US LAYERS
1. WHITE - mucosa
2. BLACK - muscularis mucosa
3. WHITE - submucosa
4. BLACK - muscularis propria
5. WHITE - serosa
10. MOST FREQUENT CAUSES
• ACUTE CHOLECYSTITIS
• HEPATIC ABSCESSES
• MASS RUPTURE
• HEPATITIS
• MYOCARDIUM ACUTE
INFARCTION
ACUTE ABDOMINAL PAIN
RIGHT UPPER QUADRANT PAIN
11. ACUTE CHOLECYSTITIS
1/3 of patients with gallstones
Main US signs:
• GB distention; transverse diameter > 4 cm
• Wall thickening > 0.3 cm
• Gallstones /impacted stone in the gallbladder
neck or cystic duct (90-95%)
• Biliary sludge (also microlithiasis)
• Sonographic Murphy sign
• US: sensitivity = 86%; specificity = 98%
12. Sonographic Murphy sign (> 90%): pain by pressure over the
sonographically visualized gallbladder (local pain with the probe)
• Wall: thickness, stratification and hypoechoic pockets (edema)
• Round gallbladder shape/ Gallstones at the body
ACUTE CHOLECYSTITIS
13. ACUTE CHOLECYSTITIS
Intense wall thickness
(edema, stratification)
Gallstones at the body
Impacted stone in the
gallbladder neck
14. • Incidence: 2- 15% of acute cholecystitis
• Risk factors: post-surgery, trauma, prolonged
patient hospitalized, severe state, diabetes,
acute pancreatitis, HIV infection, etc.
ACUTE CHOLECYSTITIS
Acalculous cholecystitis
15. Patient, male, 36 yo, in the
Intensive Care Unit (cardiac
problems), fever and
increased inflammatory
markers.
US for screenning: enlarged
gallbladder
Acalculous cholecystitis
16. ACUTE CHOLECYSTITIS
emphysematous
• Rare (< 1%)
• Gas: gas-forming bacteria in the wall or lumen (dirty
shadowing)
• Complications: gangrenous and perforation (due to
persistent obstruction)
17. ACUTE CHOLECYSTITIS
perforation
The main signs
US: GB normal
shape loss, small
defect in the wall
(focus of
perforation) and
pericholecystic
collection
5- 10% cases
Prolonged
inflammation
18. ACUTE ABDOMINAL PAIN
LEFT UPPER QUADRANT PAIN
MOST FREQUENT CAUSES
• SPLENIC ABSCESS
• SPLENIC INFARCTION
• GASTRITIS
• GASTRIC OR
DUODENAL ULCER
19. • Rare: 0.14 – 0.7 %
• Risk Factors: immunocompromised, diabetics, falciform
anaemia, septicemia, trauma, endocarditis, etc
• Clinical findings: fever, pain on LUQ, splenomegalia
• US: hypoechoic or anechoic lesion, thickening wall,
undefined margin
SPLENIC ABSCESS
Splenic Abscess in
patient HIV +
Abscess caused by candidiasis
20. SPLENIC INFARCTION
• Risk: after occlusive
procedures of splenic
artery or branches
• Clinical findings:
unspecific or pain on
LUQ and fever
• US: peripheral, wedge-
shaped, triangular and
hypoechoic lesion
• Complication: infection
21. ACUTE ABDOMINAL PAIN
RIGHT LOWER QUADRANT PAIN
MOST FREQUENT CAUSES
• ACUTE APPENDICITIS
• MESENTERIC ADENITIS
• ACUTE DIVERTICULITIS OF RIGHT
COLON
• EPIPLOIC APPENDAGITIS
• RENAL COLIC
• CROHN’S DISEASE
• INFLAMMATORY PELVIC DISEASE
• HEMORRHAGE/ RUPTURE/ TORSION
OF OVARIAN CYST
• ECTOPIC PREGNANCY
22. ACUTE APPENDICITIS
sensitivity rates
US (96 to 100%) x CT (98%)
US indications:
• Children
• Thin patients
• Pregnancy
• Fertile age women
• Operator expertise:
important!!
CT indications:
• Obesity
• Abscess with gas
(complications)
• Post-op
• Availability
• Operator expertise
Ped Rad 1998;28:147-51
Radiology 2000; 215:337-348
23. Clinical findings: Peri-
umbilical pain which
subsequently located in the
RLQ, accompanied by
nausea, vomiting, fever and
leukocytosis
Other pain locations:
• Retrocecal
• Retroileal
• Toward pelvic cavity
(true pelvis)
AJR1992; 158:773-778
ACUTE APPENDICITIS
Right
ovary
Transvaginal US
24. •Linear transducers (10-12 MHz), is recommended
•Graded compression sonography: 85% visualization1
ACUTE APPENDICITIS
techniques
1Puylaert JB. Radiology 1986;158:335-360
• Compression is essential:
1. To displace and compress bowel loops (gas and feces)
2. To decrease distance between probe and bowel (12MHz:limited penetration)
3. To assess the kind of lesion: rigid, compressible, nl x inflamed fat; by
judging its reaction upon compression
Graded manner to
avoid pain, by judging
the reaction
25. POSTERIOR MANUAL COMPRESSION
dorsal decubit and left lateral decubit: 95% visualization2
2Lee at al. AJR 2002;178:863-868
ACUTE APPENDICITIS
techniques
26. NORMAL APPENDIX
• Blind ended tube
• Compressible
• Wall thickness ≤3mm
• Diameter = 6 or 7 mm
• McBurney point
J Ultrasound Med 2000; 19:409-14
30. Compressible loss has a sensitivity of 96% and specificity of
96% for appencitis diagnosis
ACUTE APPENDICITIS
*Kessler N, Cyteval C et al. Radiology 2004;230:472-478
Appendicitis Normal appendix
Intraluminal fluid has a
sensitivity of 53%
specificity of 92%
31. US FINDINGS:
• gut signature preserved,
• lumen distended with fluid,
• wall thickness > 3mm,
• diameter increased,
• non compressible,
• inflamed fat surrounded
43. INFLAMMATORY BOWEL DISEASE
EPIPLOIC APPENDAGITIS
• CLINICAL FINDINGS: Nonspecific
abdominal pain, acute onset, most often in the
LLQ, low fever, little systemic symptoms
• US:
Hyperechoic solid lesion,
oval,
non-compressible,
thin hypoechoic halo,
adjacent to the ascending colon and sigmoid
mass effect and adjacent normal wall gut
Eur Radiol 1999;9:1886-92.
45. ECTOPIC PREGNANCY
2% of pregnancies
Cause of death during 1st trimester (9 – 14%)
SYMPTOMS AND SIGNS
• slow-rising β-hCG levels or bleeding
• Pain, a missed period
• β-hCG levels increase by less 50% - 48h (x nl ≥ 66%)
RISKS
• Previous PID/ Prior ectopic pregnancy, age ≥ 35 yo
• pelvic surgery (tubal), abdominal surgery, or multiple abortions
• history of endometriosis, infertility
• Smoking
• IUD (intrauterine device), tubal ligation,
• Congenital uterine anomalies
• Use of in vitro fertilization Lin et al. RadioGraphics 2008; 28:1661–1671
46. ECTOPIC PREGNANCY
ULTRASOUND
• point of pain exam
• free pelvic fluid (abdominal fluid) or
hemoperitoneum (pouch of Douglas)
• complex (extra) adnexial mass
• thick echogenic endometrium
• pseudogestational sac in the uterus
• empty uterine cavity
Differential diagnostic:
• pelvic inflammatory disease (PID)
• Ovarian torsion
Lin et al. RadioGraphics 2008; 28:1661–1671
59. ACUTE PANCREATITIS
“pancreas tissue acute inflammatory process,
with variable involvement in other regional
tissues and remote organs systems associated
to raised pancreatic enzyme levels in blood
and/or urinary”
• Causes: gallstones (40%), alcoholism (40%),
idiopathic (10%), other (10%)
Acta Med Port 2004;17:317-324.
Atlanta Classification , 1992.
60. ACUTE PANCREATITIS
ULTRASOUND
• US Features: enlargement of the pancreas (> 22mm)
decreased echogenicity
focal hypoechoic regions
• Complications: fluid collections, pseudocysts, abscess,
necrosis, thrombosis, pseudoaneurysms
• Role of US:
Gallstones as a cause
Bile duct dilation
Guide aspiration or drainage
Enlargement of the pancreas
64. IN CONCLUSION
• US in the emergency room: an important tool.
• Many advantages.
• US objectives: to establish the cause of pain, to locate the
pain, to stage the disease and its complications.
• Differential diagnosis!
• Signs: gas, fluid, mass, inflamed fat, gut (=caliber, wall,
persitalsis, compressible (gradual compression), tenderness
point, hyperemia).
• Importance of its limitations. Indicating CT when necessary!
• US can help treatment, guiding aspiration and drainage.
