2. Contrast-enhanced ultrasound (CEUS)
involves the administration of intravenous
contrast agents containing microbubbles of
perfluorocarbon or nitrogen gas.
The microbububbles affect ultrasound
backscatter and increase vascular contrast in
a similar manner to intravenous contrast
agents used in CT and MRI
3. Microbubble shell material determines how
easily the microbubble is taken up by
the immune system.
The material for microbubble determines its
time in circulation and elasticity.
Microbubble shells are composed
of albumin, galactose, lipid, or polymers
Microbubble gas core is the most important
part because it determines the echogenicity.
4. Size of Microbubble is around 1 - 4 μm.
The Microbubble is nearly around the size of
RBCs as it should not cross the vascular
endothelium.
6. Echovist- Used in Right heart Myocardium,
Liver and gynaecological applications.
Albunex- used in Liver, Kidneys and heart
contrast imaging.
SonoVue- Most Commonly used in INDIA.
Used in study of Liver, Kidneys and
Gynaecological studies.
7. DOSE- . SonoVue is a kit including 1 vial
containing 25 mg of lyophilised powder and
second vial contains suspension medium
(Galactose solution)
For I.V. use dose for SonoVue is 2.4 ml
(0.04ml/kg).
For renal and pancreatic evaluation low dose
1.0ml is used.
10ml 0.9% N.S should be flushed after the
administration of the contrast agent.
8. PROCEDURE-
The suspension should be administered
before 15mins after preparation.
The target organ is focused on B-mode US
and then contrast-specific imaging mode is
turned on.
On Ultrasound after the contrast is
administered the tissue is divided on basis of
Perfussion i.e Hyperenhancing, isoenhancing,
hypoenhancing.
10. More common method
In this the microbubbles will remain in the
systemic circulation for a certain period of
time. During that time, ultrasound waves
are directed on the area of interest. When
microbubbles in the blood flow past the
imaging window, the
microbubbles’ compressible reflect a
unique echo.
11. To enhance the contrast at the interface
between the tissue and blood. A clearer
picture of the structure of an organ
Evaluating the degree of blood perfusion
and evaluating the blood volume in an
organ or area of interest.
Differentiation between benign and
malignant focal liver lesions
12. Typical appearance of liver hemangioma (arrows). CEUS
shows globular peripheral enhancement 40
seconds after microbubble injection (A) and progressive,
centripetal fill-in after 90 seconds (B). The central
portion of the lesions remains unenhanced because of
incomplete filling in.
13. Appearance of prostate cancer at CEUS. (A) Baseline transrectal
US of the prostate shows no focal abnormalities in the peripheral
portion of the gland. (B) Twenty-eight seconds after microbubble
injection a hypervascular area is recognized in the right prostate
lobe (arrowheads). Cancer was found at biopsy
14. Acute splenic infarction from septic embolism in a patient with
aortic valve prosthesis infection and bacterial endocarditis. (A)
No defined abnormalities of the splenic parenchyma are seen on
baseline US. (B)CEUS image obtained 30 seconds after
microbubble injection shows a large, nonperfused area (*)
involving the dome of the spleen
15.
16. Contrast agents designed to bind to specific
molecules, which are then targeted at
tissues expressing that substance.
Microbubbles targeted with ligands that
bind certain molecular markers that are
expressed by the area of imaging.
Microbubbles theoretically travel through
the circulatory system, eventually finding
their respective targets and binding
specifically.
17.
18. Inflammation: Contrast agents may be designed to
bind to certain proteins that become expressed in
inflammatory diseases such as Crohn's
disease, atherosclerosis, and even heart attacks
Thrombosis and thrombolysis: Contrast Agents
specifically bind to activated platelets and allow
real-time molecular imaging of thrombosis, such
as in myocardial infarction, as well as monitoring
success or failure of pharmacological thrombolysis.
19. Cancers: If microbubbles are targeted with
ligands that bind receptors like VEGF, they
can non-invasively and specifically identify
areas of cancers.
Drug Delivery: drugs can be incorporated
into the microbubble’s lipid shell.
Gene Delivery: Vector DNA can be
conjugated to the microbubbles
20.
21. Complex hepatic cyst (curved arrows). (A) Baseline US
showing a heterogeneous round lesion with well-
defined margins but no defined posterior
enhancement. (B) After microbubble injection the lesion
does not enhance in all vascular phases.
22.
23.
24. ADVERSE EVENT FREQUENCY
0.5-5 %
FREQUENCY
<1%
SYSTEMIC HEADACHE
HYPERSENSITIVITY
ABDOMINAL PAIN
WEAKNESS
CHEST PAIN, BACK
PAIN.
CARDIOVASCULAR HYPERTENSION ATRIAL FIBRILATION
PALPITATION,
TACHYCARDIA
DIGESTIVE SYSTEM NAUSEA ANOREXIA , DIARRHEA,
DYSPEPSIA
MSK, CNS DIZINESS, DRYMOUTH,
VASODILATATION
LEG CRAMPS,
PARESTHESIA
RESPIRATORY, SKIN DYSPNOEA, SWEATING,
RASH, PRURITUS
SPECIAL SENSES ALTERED TASTE, SMELL.
25. To reduce the risk Check for
intolerance of any of the components
of the contrast agent
Use the lowest level of acoustic output
and shortest scanning time to allow a
diagnostic examination
Management of Drug reactions is
symptomatic.
26. Acoustically homogeneous. Blood and
surrounding tissues have similar
echogenicities, so it is also difficult to clearly
discern the degree of blood flow, perfusion,
or the interface between the tissue and blood
using traditional ultrasound.
Allows real-time evaluation of blood flow.
Destruction of microbubbles by ultrasound in
the image plane allows absolute
quantification of tissue perfusion.
It does not involve radiation.
27. Very cost-efficient and widely
available.
Since microbubbles can generate such
strong signals, a lower intravenous
dosage is needed, micrograms of
microbubbles are needed compared to
milligrams for other molecular imaging
modalities such as MRI contrast agents.
Targeting strategies for microbubbles
are versatile and modular.
Active targeting can be increased
(enhanced microbubbles adhesion)
by Acoustic radiation force using a
clinical ultrasound imaging system in
2D-mode and 3D-mode.
28. Microbubbles don’t last very long in circulation.
They have low circulation residence times
because they either get taken up by immune
system cells or get taken up by the
liver or spleen even when they are coated with
PEG.
Ultrasound produces more heat as the frequency
increases. Monitering Required.
Microbubbles burst at low ultrasound frequencies
and at high mechanical indices (MI), which is the
measure of the acoustic power output of the
ultrasound imaging system. Increasing MI
increases image quality, but there are tradeoffs
with microbubble destruction. Microbubble
destruction could cause local microvasculature
ruptures and hemolysis.
29. Targeting ligands can be immunogenic, since
current targeting ligands used in preclinical
experiments are derived from animal culture.
Low targeted microbubble adhesion
efficiency. This is main reasons that targeted
contrast-enhanced ultrasound remains in the
preclinical development stages.
