Transcript X-Ray Interpretation

X-ray Interpretation
Objectives
• List the reasons for obtaining a Chest x-ray
•Identify anatomical structures present on a chest
film.
• Recognize a normal chest radiograph.
• Recognize and name the radiographic signs of
atelectasis, consolidation, pneumothorax, pleural
effusions, and hyperinflation frequently seen in
patients with cardiopulmonary disease.
A Chest x-ray is very valuable in
answering the following questions
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Is the heart enlarged or normal?
Are there signs of heart failure and fluid overload?
Does the patient have pneumonia or a collapsed lung?
Is there evidence of emphysema?
Are there findings of an aneurysm involving the aorta?
Is there fluid in the sac that surrounds the lung?
Is there free air under the diaphragm to suggest a hole in
the bowel wall?
• Is there a tumor in the lung that could represent cancer?
• Are there changes of bronchitis or emphysema?
Standard PA or posterior – anterior
Radiograph
•Patient usually upright
•Distance of beam
determines magnification
and clarity
• Place the films on the
view box as though you
were facing the patient
with his left on your right
side.
Standard Lateral Chest Radiograph
• Left side of the chest against
filmholder (cassette); beam
from right at a distance of six
feet;
• Lesions located behind the left
side of the heart or in the base
of the lung are often invisible
on the PA view because the
heart or diaphragm shadow
hides it
– the lateral will generally show such
lesions
X-rays are a study of densities
• DENSITIES Air < fat < liver < blood < muscle < bone <
barium < lead.
• Air — least dense; most transparent or radiolucent;
unobstructed beam or air-filled densities appear black
– Lungs, gastric bubble, trachea, ? bifurcation of bronchi
• Fat — breasts
• Fluid — most of what you see; vessels, heart,
diaphragm, soft tissues, mediastinal structures
• Mineral — most dense (or radiopaque) of body
structures; mostly Ca++; bones (marrow is aerated),
aortic calcifications such as the aortic knob, ? calcification
of the coronary arteries, old granulomas; bullets, safety
pins, etc.
Different Densities on an ICU Chest X-ray
Anatomy
Silhouette Sign / Air Bronchogram
What am I looking at?
What am I looking at?
Right Upper Lobe
Right Middle Lobe
Right Lower Lobe
Left Upper Lobe
Left Lower Lobe
Normal Cardiac Anatomy
(PA view)
Normal Cardiac Anatomy
(Lateral view)
Pleura
How to Read a Chest X-ray
• Go from general observations to specific details.
– Sometimes a change may be so major that the old saw about
missing the forest for the trees comes true.
• Read the Chest X-ray in a systematic fashion:
– L shoulder
– L chest wall
– Lower Chest
– R chest wall
– R shoulder
– Cervical spine and soft tissue
– Chest / Ribs
– Hilum
– Lungs
– Pleura
LEFT SHOULDER GIRDLE
• Soft tissues - look at overall amount, then
check for the following: calcifications,
obvious mass effect, abnormal air collections
• Bones - look at each bone for abnormalities
• Joints- are articular relationships normal, joint
spaces narrowed, widened, any calcification
in the cartilages, air in the joint space,
abnormal fat pads, etc.
LEFT SHOULDER GIRDLE
LEFT CHEST WALL
• Look for overall
thickness,
subcutaneous
emphysema,
calcification.
• Look for sharp, distinct
muscle fat planes
BREAST TISSUE
•In males and females, some
asymmetry can occur from
standing with unequal
pressure against the film
holder.
•Notice how the apparent
lung density changes from
the lung area covered by the
soft tissue of the breast to
the lung area inferior to the
breast.
ABDOMEN
• The visibility of structures
is highly variable
• Gastric and bowel gas - Is
amount and location
normal?
• Check for free peritoneal air
– position of patient will
change location of free air.
• Look for calcifications and
masses - can they be
localized to a specific
structure.
RIGHT CHEST WALL
• Look for overall
thickness,
subcutaneous
emphysema,
calcification.
• Look for sharp,
distinct muscle fat
planes.
RIGHT SHOULDER GIRDLE
NECK SOFT TISSUES AND SPINE
• Amount of soft tissue,
presence of calcifications,
subcutaneous emphysema,
position and size of trachea.
• For the cervical spine, check
alignment and note any major
congenital abnormalities.
• Then look at specific parts of
the vertebra and disc spaces,
checking for erosions, boney
destruction, disc / joint
narrowing or other
abnormalities.
THORACIC SPINE AND RIB CAGE
• Concentrate on the skeletal
detail -- "look through" the
mediastinum and lungs.
• First check overall alignment
of the spine and symmetry of
the rib cage, double check
bone density (this is a gross
estimate).
RIBS
• Compare individual ribs
side to side
1. Posterior rib
2. Anterior Rib
Hilum (pleural = hila.)
• "lung root;" medusa-like tangle of arteries
and veins on either side of the heart
shadow.
• Irregular medial shadow in each lung where
the bronchi and pulmonary arteries enter.
• Other structures in these areas, particularly
lymph nodes, are normally so small as to be
unapparent.
Pulmonary hilum
FRONTAL VIEW OF THE HILA
• On the frontal view most
of the hilar shadows are
the left and right
pulmonary arteries.
• The left pulmonary artery
is always more superior
than the right, thus
making the left hilum
appear higher.
• Calcified lymph nodes
may be visible within the
hilar shadows.
LATERAL VIEW OF THE HILA
Hilar Adenopathy
Hilar Adenopathy
Lungs
LUNGS
• Compare overall size
of one lung to the
other,
• Look for major areas
of abnormal lucency or
density
Pleura
Pleura
• Check the frontal view for minor fissure
thickness and location, and on the
lateral view, look for minor and major
fissures
• These are normally fine delicate
structures that do not show up on the
digitized images.
Pleura
Stomach Anatomy
Let’s look at some examples
Terminology
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Silhouette sign
Atelectasis
Consolidation
Pneumothorax
Pleural effusion
Nodule
Hyperinflation
Loculated
Lateral Decubitus
Silhouette Sign
When two objects of the same
density touch each other, the
edge between them disappears
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B
Using the Silhouette Sign
•Right middle lobe silhouettes right heart
border
•Lingula silhouettes left heart border
•Right lower lobe silhouettes right
hemidiaphragm
•Left lower lobe silhouettes left
hemidiaphragm
Silhouette Sign
Silhouette of the Right Heart Border
Right middle
lobe Infiltrate
showing
obliteration of
the right heart
border
Atelectasis = collapse (volume
loss)
• To diagnose atelectasis,
there must be evidence of
volume loss such as
displacement of a fissure or
hilum.
Atelectasis of right lung – shift of the mediastinal
structures TOWARDS the side of opacification
Tension Pneumothorax
Pleural Effusion
Loculated Hydropneumothorax
Pulmonary Nodule
Hyperinflation
Hyperinflation
Pneumonia
Final Exam
Conclusion
• Should be able to look at a CXR and
determine whether it is normal
• Identify obvious abnormalities on the CXR,
including boney, soft tissue, cardiac and
pulmonary pathology
• Be able to understand basic radiology
terminology