4. • Diagnostic ultrasonography
is the only clinical imaging
technology currently in use
that does not depend on
electromagnetic radiation.
5. • U/S probes emit and
receive the energy as
waves to form pictures
6. Ultrasound Transducer
Speaker
transmits sound pulses
Microphone
receives echoes
• Acts as both speaker & microphone
Emits very short sound pulse
Listens a very long time for returning echoes
• Can only do one at a time
9. High Frequency
• High frequency (5-10 MHz)
greater resolution
less penetration
• Shallow structures
10. Low Frequency
• Low frequency (2-3.5 MHz)
greater penetration
less resolution
• Deep structures
11. Displays
• B-mode
– Real time gray scale, 2D
– Flip book- 15-60 images per second
• M-mode
– Echo amplitude and position of moving
targets
– Valves, vessels, chambers
15. Image properties
• Echogenicity- amount of energy
reflected back from tissue interface
– Hyperechoic - greatest intensity - white
– Anechoic - no signal - black
– Hypoechoic – Intermediate - shades of
gray
19. Acoustic Enhancement
• Opposite of acoustic shadowing
• Better ultrasound transmission allows
enhancement of the ultrasound signal
distal to that region
21. Acoustic Shadowing
• Occurs distal to any highly reflective or
highly attenuating surface
• Important diagnostic clue seen in a
large number of medical conditions
– Biliary stones
– Renal stones
– Tissue calcifications
22. Acoustic Shadowing
• Shadow may be more prominent than
the object causing it
• Failure to visualize the source of a
shadow is usually caused by the object
being outside the plane of the
ultrasound beam
26. Reverberation Artifacts
• On the monitor parallel bands of
reverberation echoes are seen
• This causes a “comet-tail” pattern
• Common reflective layers
– Abdominal wall
– Foreign bodies
– Gas
38. Normal lung surface
Left panel: Pleural line and A line (real-time).
The pleural line is located 0.5 cm below the rib line in the adult.
Its visible length between two ribs in the longitudinal scan is
approximately 2 cm. The upper rib, pleural line, and lower rib (vertical
arrows) outline a characteristicpattern called the bat sign.
40. Rock the probe slightly side to side
until the pleura is in sharp focus
Pleura not at right angles
to probe so indistinct
Correct angle =
sharpest edge.
43. A lines = default normal
Horizontal echo
reflection at exact
multiples of intervals
from surface to
bright reflector.
Dry lung OR PNTX
Decay with depth
Obliterated by B
pleura A
A
A
A
A
A
44.
45. B lines = fluid in alveolus or
interstitium
Originates from
pleural line
Reaches base of
screen OR ALMOST
MORE THAN 2 at
once is abnormal
EXCEPT in lung base
Remember as
„Kerley Bs‟
Not exactly the
same.
RIB
RIB
B B B BB
47. Confluent B lines = Bad Bad
„White‟ or „shining‟
lung
Means increased
severity
Probably indicates
thicker fluid in alveoli
eg protein or
inflammatory cells
% space / 10
48. B x 3 x 2 x 2 = CCF
Makes assumption that „globally‟ wet
lungs are most likely to be CCF
12
49. Normal lung surface
Left panel: Pleural line and A line (real-time).
The pleural line is located 0.5 cm below the rib line in the adult.
Its visible length between two ribs in the longitudinal scan is
approximately 2 cm. The upper rib, pleural line, and lower rib (vertical
arrows) outline a characteristicpattern called the bat sign.
74. *The amount of pleural fluid can be estimated
by the following formula:
V (ml)= 20 x Sep
V = volume, Sep = maximal distance between
the two pleura layers.
*For sitting patients a good method is to
calculate the sum of the basal lung to
diaphragm distance and the lateral height of the
effusion and to multiply the sum by 70.
Quantification of Pleural Fluid:
80. Absent lung sliding
Exaggerated horizontal artifacts
Loss of comet-tail artifacts
Broadening of the pleural line to a band
Lung point
Loss of lung impulse
The key sonographic signs of
Pneumothorax
87. Thoracic ultrasound examination is considered positive for
interstitial syndrome when at least two scans per side show
multiple B lines:
in this case (cardiogenic pulmonary edema), positive scans are detected all
over the anterolateral chest.
100. Am. J. Respir. Crit. Care Med.,
Volume 156, Number 5, November
1997, 1640-1646
The Comet-tail Artifact
An Ultrasound Sign of Alveolar-
Interstitial Syndrome
101. Pneumonia
• It is commonly visualized by TUS as a
hypoechoic consolidated area of varying size
and shape, with irregular borders.
• The echotexture can appear homogeneous or
inhomogeneous.
• The most common sonographic feature of
pneumonia is the air bronchogram, which is
characterized by lens-shape internal echoes
within the hypodense area or echogenic lines
and corresponds to air inclusions or air-filled
bronchioles and bronchi.
106. Pneumonia
Posterior intercostal scan shows a hypoechoic
consolidated area that contains multiple
echogenic lines that represent an air
bronchogram.
107. Pneumonia; fluid bronchogram
• Conversely, the fluid
bronchogram is characterized
by anechoic or hypoechoic
tubular structures in the
bronchial tree.
108. Post-stenotic pneumonia
Posterior intercostal scan shows a hypoechoic
consolidated area that contains anechoic,
branched tubular structures in the bronchial tree
(fluid bronchogram).
109. Pleural effusion and alveolar consolidation; typical
example of PLAPS.
Lichtenstein D A , Mezière G A Chest 2008;134:117-125
110. A 45-year-old patient presenting in the emergency department with cough, pleuritic pain and
dyspnoea. Double-view chest x-ray showed no sign of pneumonia (A, B). A CT scan (C)
confirmed the presence of a right basal consolidation shown by lung ultrasound (D).
111. Summarizing Sonographic
findings in pneumonia
• • Liver like in the early stage
• • Air bronchogram
• • Lenticular air trappings
• • Fluid bronchogram (poststenotic)
• • Blurred and serrated margins
• • Reverberation echos in the margin
• • Hypoechoic abscess formation
112. Lung abscesses
• They typically appear as round or oval, largely
anechoic lesions.
• In the early stage, small abscesses are visible as
a pathological collection of fluid irregularly
settled in a consolidated, liver-like infiltrate.
• Depending on the capsule formation, the edge
of the abscess can be smooth and echodense.
• Microabscesses are often visible as anechoic
areas within the pneumonic consolidation.
114. Lung abscess with air inside the lesion
A: High amplitude echoes
are clearly visible (arrow), as
well as multiple echogenic
small air inclusions
(arrowheads);
B: Corresponding computed
tomography scan shows the
same findings
115. Contrast-enhanced ultrasonography
of pneumonia
A: Baseline scan shows
a hypoechoic
consolidated area
B: Seven seconds after
iv bolus of contrast
agent, the lesion shows
marked and
homogeneous
enhancement
C: The lesion remains
substantially unmodified
after 90 s.
116. Contrast-enhanced ultrasonography evaluation of
pneumonia with pleural effusion.
Baseline scan shows parenchymal
consolidation with air bronchogram
(arrows) and subtle surrounding
effusion (arrowheads)
After iv bolus of contrast agent, the
consolidation is enhanced and better
demarcated from the effusion
117. Lung abscess at CEUS
.A: An anechoic oval
lesion is surrounded
by an echodense
capsule;
B: After iv bolus of
contrast agent, the
lesion shows no
contrast agent uptake,
whereas the capsule is
strongly enhanced
119. Contrast-enhanced ultrasonography of bronchial
carcinoma
A: Baselinescan showsa hypoechoic
lesionwith irregularborders
Ten seconds after iv bolus of
contrast agent, the pulmonary
parenchyma near the lesion is
already enhanced (arrows),
whereas the lesions is still
unenhanced
B:Twenty seconds later, the lesion
shows delayed inhomogeneous
enhancement, which indicates a
preferential bronchial arterial supply
120. Pulmonary embolism (PE)
• The sensitivity of TUS for PE has been estimated to
range from 80% to 94%, the specificity from 84%
and 92%, and the overall accuracy from 82% to
91%.
• Although CTPA is undoubtedly the method of
choice to obtain a definitive diagnosis of PE, TUS
should be taken into consideration in some
circumstances, particularly in critically ill patients
who might not tolerate transport for other imaging
modalities, in cases of pregnancy, contrast agent
allergy, or renal failure.
122. Dynamic course of pulmonary infarction
A: Lateral intercostalscan of
the right lung shows a typical
triangular-shapedperipheral
lesion;
B: computed tomographyscan
of the lateral segment of the
lowerright lobe showsa
triangularpleural-basedlesion
with the vertex towards the
hilum
C: After 40 d, the lesion is no
longer visible by computed
tomography scan;
D: The lesion appears reduced
in size at transthoracic
ultrasonography examination.
123. Pulmonary embolism. A 1.2 – 1.5 mm triangular subpleural
lung consolidation. B. Vascular sign at the margin, not central
124. •On color Doppler sonography,
PE-based peripheral lesions do
not show flow signals inside,
a phenomenon defined as
“consolidation with little
perfusion”
125. Sonomorphology of peripheral pulmonary
embolism
• Echopoor
• Well demarcated
• 1-3 (0.5-7) cm in size
• Pleural based
• Triangular > rounded
• Central bronchial reflexion (> 3 cm)
• Vascularization stop
• 2.5 lesions/patient on average
• 2/3 dorsobasal located
• Small pleural effusion
126. Schematic representation of the parenchymal, pleural and vascular
features associated with pulmonary embolism.(Angelika Reissig, Claus
Kroegel. Respiration2003;70:441-452)
127. The Late sign of atelectasis:
• The late sign appeared when the air inside the
consolidation was progressively absorbed, which
yielded a loss of volume of the lesion with the
typical static air bronchogram inside.
• Pleural effusion is almost always associated with
compression atelectasis and frequently with
obstructive atelectasis.
• In the case of compression atelectasis, the
effusion is typically larger compared to that
associated with obstructive atelectasis.
129. Contrast-enhanced ultrasonography
evaluation of compression atelectasis.
Baseline scan shows a liver-like
consolidation surrounded by
multiloculated pleural effusion
Twelvesecondsafter iv bolus of contrast agent,
the consolidationshows marked and
homogeneousenhancement, whereas pleural
effusion showsno enhancement.
130. Obstructive atelectasis
• It shows a liver-like and inhomogeneous
echotexture with secretion-filled bronchi (fluid
bronchogram) and variable shape.
• The real-time TUS visualization of
bronchograms during breathing movements can
often enable one to distinguish between
obstructive atelectasis and pneumonia.
• The presence of the dynamic air bronchogram
indicates pneumonia, while a static air
bronchogram suggests obstructive atelectasis.
131. Posterior intercostal scan shows a hypoechoic consolidated
area that contains anechoic, branched tubular structures in
the bronchial tree (fluid bronchogram).
132. CEUS in Peripheral bronchial
carcinomas
CEUS can help to define better necrotic areas
that are depicted as anechoic regions inside
the enhanced viable tumor.
The infiltrative growth of solid tissue without
regard to anatomical structures is
characteristic of malignancy
134. Contrast-enhanced ultrasonography
evaluation of bronchial carcinoma.
Baseline scan shows
consolidation with
inhomogeneous echotexture.
Twenty secondsafter iv bolus of
contrast agent, necroticareas can
be depictedas anechoicregions
insidethe enhancedviable tumor
135. Bronchial carcinoma infiltrating the pleural wall.
A: Posterior intercostalscanshows
a hypoechoiclesionaccompanied
by rib destruction (arrows);
B: Twenty-four secondsafter iv bolus
of contrast agent, the lesionappears
inhomogeneouslyenhanced;the
disrupted rib appears more
echogenicthan the tumor
(arrowheads), as a consequenceof
the incompletetissue suppression
due to the strong echogenicityof
bone tissue.
137. Prof.Maha KGhanem,MD, FCCP
Lung cancer. A rounded, tumoral fringes,
central echopoor necrotic lesion with B
irregular neovasculaization
138. Sonomorphology of pulmonary
carcinomas
• Hypoechoic, inhomogeneous
• Rounded, polycyclic
• Sharp, serrated margins
• Ramifications and fringes
• Infiltration of chest wall
• Irregular vascularization
139.
140. Us is increasingly used to guide interventional
procedures of the chest including:
1- Interventional procedures of the pleural
space.
* Thoracentesis and catheter drainage.
* Pleural biopsy.
2-Pulmonary interventional procedures
* Us guided lung biopsy (Lung cancer – Pneumonia).
* Drainage of lung abscesses.
3- Mediastinal intervention.
* Biopsy of mediastinal mass and lymph nodes.
4- Chest wall intervention.
* Biopsy of chest wall mass.
141. For performance of the US guided thoracic
intervention, the following are required:
1- The procedures could be performed on an out
patient basis.
2- The procedures may be carried out in any room.
3- Special puncturing equipment should be
available.
4- The patient must be informed of the course and
risk of the procedure.
5- The coagulation status should be known.
6- Acknowledging preexisting finding (bronchoscopy –
chest radiograph – CT).
7- The sonographic status of the thorax is evaluated.
142. The US guided procedure can be performed
with either of the following:
A) The free- hand technique after sonographic
location.
B) The free- hand technique under sonographic
observation.
C) The guided technique through applicator added to
the US probe.
D) The guided technique by special transducer
probe with a notch in the middle allows the
insertion of the needle in a fixed direction.
143. The free - hand technique after
sonographic location.
144. The free- hand technique under
sonographic observation.
146. The guided technique by special transducer
probe with a notch in the middle allows the
insertion of the needle in a fixed direction.
147. Follow – up after intervention:
Three hours of surveillance after
intervention.
Sonographic check before discharge.
Instruction for patient (immediate return to
the hospital in case of symptoms).
148. Contraindications:
A) Absolute (severe blood coagulation disorders)
* International normalized ratio (INR) more than 1.8.
* Partial thromboplastin time (PTT) more the 50s.
* Platelet count below 50,000.
B) Relative
* Bullous pulmonary emphysema.
* pulmonary hypertension.
(N.B) when respiratory function is severely impaired or
blood gas values are poor, the procedure should only be
performed when the patients condition is expected to be
improved by the therapeutic intervention.
149. Risks of US guided thoracic interventions:
* The rate of pneumothorax is 2.8 %; 1%
require drainage.
* Hemorrhage or hemoptysis is observed in
0-2 %.
* Tumor dissemination through the
procedure of puncture is very rare (Less
than 0.003 % of cases).
162. c
At the bedside, chest radiography remains the reference for lung imaging in
critically ill patients. However, radiographical images are often of
limited quality
• Movements of the chest wall
• Film cassette posterior to the
thorax
• X-ray beam originating anteriorly, at
a shorter distance than
recommended and not tangential to
the diaphragmatic cupola .
Mistaken assessment
of :
c
• Pleural effusion
• Alveolar consolidation
• Alveolar-interstitial
syndrome
Bedside Chest Radiography in the Critically
ill
02 09 2012
164. Clinical applications of lung ultrasonography in the
intensive care unit
1. Diagnosis of pulmonary consolidation.
2. Diagnosis of atelectasis
3. Diagnosis of alveolar-interstitialsyndrome
4. Differentiating between pulmonary oedema and ARDS
5. Differentiating between pulmonary oedema and COPD
6. Diagnosis of pulmonary embolism
7. Diagnosis of pneumothorax
8. Diagnosis and estimation of volume and nature of pleural effusion.
9. Diagnostic and therapeutic ultrasound-guided thoracentesis.
165.
166.
167.
168.
169.
170.
171.
172.
173.
174.
175. Duplex Doppler sonogram of a 5 x 3 cm hypoechoic mass
(adenocarcinoma) in upper lobe of left lung shows blood flow
at margin of tumor near pleura. Spectral waveform reveals
arteriovenous shunting: low-impedance flow with high
systolic and diastolic velocities. Pulsatility index = 0.90,
resistive index = 0.51, peak systolic velocity = 0.47 m/sec, end
diastolic velocity =0.23 m/sec, peak frequency shift = 3.8 kHz,
176. Duplex Doppler sonogram in 67-year-old man with pulmonary
tuberculosis in lower lobe of left lung shows several blue and
red flow signals in massiike lesion. Spectral waveform reveals
high-impedance flow. Pulsetility index = 4.20, resistive index =
0.93, peak systolic velocity = 0.45 m/sec, end diastolic
velocity = 0.03 m/sec, Doppler angle = 21#{
182. Background
Patients with shock have high mortality rates and these
rates are correlated to the amount and duration of
hypotension.
Diagnosis and initial care must be accurate and prompt
to optimise patient outcomes.
Studies have demonstrated that initial integration of
bedside ultrasound into the evaluation of the patient with
shock results in a more accurate initial diagnosis with
earlier definitive treatment.
Bedside USS allows direct visualisation of pathology or
abnormal physiological states.
183. Remember…
Ultrasound is a tool to aid diagnosis, but it won’t tell you
everything…
When using it we should always have a clinical question you
would like it to answer
186. Parasternal long axis
Transducer at left sternal
edge between 2nd -4th
intercostal space
Probe marker pointing to
patients R shoulder
Probe aligned along the
long axis: from R shoulder
to cardiac apex.
Useful view to assess
contractility
187. Apical 4 chamber
Transducer at 4th-6th intercostal
space in the midclavicular to
anterior-axillary line.
Probe directed towards patient’s
right shoulder with the marker
directed towards the left
shoulder.
Important view to give relative
dimensions of L and R ventricle.
Normal ventricular diameter
ratio of R ventricle to L ventricle
is <0.7.
188.
189. PericardialTamponade
Remember tamponadeis a clinical diagnosis based on
patient’s haemodynamics and clinical picture.
Ultrasound may demonstrate early warning signs of
tamponade before the patient becomes haemodynamically
unstable.
Haemodynamic effects
Its PRESSURE NOT SIZE THAT COUNTS!
Rate of formation affects pressure-volume relationship and
is therefore more important than volume of fluid.
190. Tamponade using ultrasound
A moderate-large effusion.
Right atrial collapse
Atrial contractionnormal in atrial systole
Collapse throughout diastole or inversion is abnormal.
RV collapse during diastole when meant to be filling
(‘scalloping’ seen)
Whats seen in the IVC…
192. Where to put the probe…
Probe position
Subxiphoid
Orientate probe in
longitudinal plane with
probe indicator to
patient‟s head
Slightly to right of
midline
194. The FAST view…
Probe goes longitudinally in right mid axillary line with
marker towards head.
Look for IVC running longitudinally adjacent to the liver
crossing the diaphragm
Track superiorly until it enters the RA confirms it’s the IVC not
the aorta
195. Assessing the IVC
During inspiration, intrathoracic pressure becomes more
negative, abdominal pressure becomes more positive,
resultant increase in the pressure gradient between the
supra and infra-diaphragmatic vena cava, increases
venous return to the heart.
Given the extrathoracic IVC is a very compliant vessel
this causes diameter of IVC to decrease with normal
inspiration.
In patients with low intravascular volume, the inspiration
to expiration diameters change much more than those
who have normal or high intravascular volume.
196. Estimating theCVP
IVC Diameter (mm) % collapse Estimated CVP (cm
H2O)
<20 >50 5
<20 <50 10
>20 <50 15
>20 0 20
Right atrial pressures, representing central venous pressure, can be estimated
by viewing the respiratory change in the diameter of the IVC.
205. himaP
Multiple studies have shown ultrasound to be more
sensitive than supine CXR for the detection of
pneumothorax.
Sensitivities ranged from 86-100% with specificities from
92-100%.
Furthermore USS can be performed more rapidly at the
bedside.
Detection with ultrasound relies on the fact that free air is
lighter than normal aerated lung tissue, and thus will
accumulate in the nondependent areas of the thoracic
cavity. (ie anteriorly when patient is supine).
206. To get the lung window
Patient should be supine.
Use high frequency linear
array or a phased array
transducer.
Position in the
midclavicular line, 3rd to 4th
intercostal space with
probe oriented
longitudinally.
Position between ribs.
