Pulmonary Radiology
Rui Domingues, MD
Lincoln Mental and Medical Center
September 2008
Pulmonary Imaging

Imaging techniques used to investigate
pulmonary pathology include:
Plain film
 Computed Tomography
 Magnetic Resonance Imaging
 Ultrasound
 Angiography

Keys to reading X-rays well
1.
2.
A good understanding of normal
anatomy
A good search pattern
But before we can do this we need to
understand how x-rays are produced.
Things to cover…

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Radiographic basics
How to approach a chest x-ray
Normal radiographic anatomy
Radiographic Basics
What causes the blacks, whites
and grays of an x-ray image?


X-ray beams contains x-ray photons of
differing energies
As these photons pass through a
patient…



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Some are absorbed completely
Some penetrated directly to the plain film
Some are absorbed partially, and
While others are deflected (Scatter)
Tissue Density


A product of the type of tissue and the
thickness of that tissue
Results in differential absorption
Differential Absorption


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Penetration of the x-ray beam is dependent
on tissue density
Denser object = less penetration
Less beam striking the film (more absorption)
= WHITER
More beam striking the film = BLACKER
Air
Glass
Test Tube
Fat
Water
Bone
+
Water
Metal
Differential Absorption
Black
Air (Lungs / Trachea / Outside the body)

Fat (Perirenal fat / Fascial plane)

Water (Muscle / Organs)

Bone (Bone / Atherosclerotic plaquing)
White
Metal (Fillings / Markers / Ortho devices)
Radiographic Image


Adjacent structures of similar densities
are not visualized
Kidney (water density) against liver
(water density)
Radiographic Image


Adjacent structures of different
densities are visualized
Liver (water density) next to Bowel (air
density)
Chest Films

Minimum Diagnostic Series


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PA
Left Lateral
Additional Views


Apical Lordotic
Inspiration / Expiration
PA CXR
Left Lateral CXR
Apical
Lordotic
CXR
Allows for
better
visualization
of the
Apices of
the lungs
Expiration
Inspiration
Inspiration study
Expiration study
Normal positioning
for PA Chest
Helps visualize:
- Small Pneumothorax
- Air Trapping Dz
(Emphysema)
- Bronchial obstruction
Visualizes respiratory excursion
How to approach an X-ray?
Reading a Chest X-ray

First thing:


Correctly put of the film
Then perform your search pattern


which you always follow when looking at any film
this way you will miss fewer findings
Reading a radiograph


Start reading every radiograph by
scanning the areas of least interest first,
working your way to the more
important areas.
You will be less likely to miss important
secondary findings.
Chest Film Search Patterns

ABCs

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Abdomen
Bone
Chest
Soft tissues

ATMLL


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Abdomen
Thorax
Mediastium
Lung
Lung
These are the two main search patterns that people
use when evaluating a chest film.
“ATMLL” Search Pattern

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Remember
A = Abdomen
T = Thorax
M = Mediastinum
L = Lungs (unilaterally)
L = Lungs (bilaterally)
Searching the “Abdomen”

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Scan across the upper abdomen several times
Evaluate normal gas containing structures:
 Stomach
 Hepatic flexure of the colon
 Splenic flexure of the colon
Evaluate the liver and on occasion one can
visualize the spleen
Structures Visualized:
Stomach gas bubble
Splenic flexure
Liver
Hemidiaphragms
Abdomen dz that can
mimic Lung disease
include:
Subphrenic abscess
Diaphragmatic hernia
Hiatal Hernia
Searching the Bony “Thorax”

Start at the right base, look at the soft tissues
of the chest wall, ribs, spine and shoulder
girdle

Go up one side and come down on opposite
side

Remember:


Posterior ribs descend medial to lateral
Anterior ribs descend lateral to medial
Structures Visualized:
Breast Tissue
Posterior Ribs
Anterior Ribs
Scapula
Clavicle
Spine
Thorax cage dz that may
stimulate chest dz:
Bony metastasis
Rib / Clavicle fractures
Searching the “Mediastinum”

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An organized search of the mediastinum
is complicated because of all the
overlapping structures.
Start with a global look for contour
abnormalities, then follow with a more
detailed search
Three searches of the
mediastinum:
1. Trachea
Tracheaand
andcarina
carina
2. Aorta
Aortaand
andthe
the
heart
heart
3. Hilum
Hilum
Searching the “Lungs”


Since most chest x-rays are ordered to
evaluated for lung disease, so the lungs are
examined last.
They are important, so their evaluation
should be more through, therefore we
evaluate them twice.


Once individually
Second time comparing right and left
Structures Visualized:
Costophrenic angles
Lung fields
Pulmonary vasculature
Right minor fissure
Left Lateral Chest Film

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Valuable radiographic study
Helps to better localize lesions
Allows to visualize overlapping tissues
Allows the visualization of hidden
pathology
Searching the Lateral Chest Film

The pattern is the same:
1) Abdomen
2) Thoracic cage strutures
3) Mediastinum
4) Lungs
Search Pattern:
Abdomen
Abdomen
Thoraciccage
Thoracic
cage
and
and
bones
bones
Mediastinum
Mediastinum
Lungs
Lungs
What to look for…

Abnormal density

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Abnormal shape

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Lung field
Mediastinum
Abnormal size

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Usually air versus water
Lung field
Mediastinum
Abnormal location

Hemidiaphragm, hila, mediastinum, trachea,
fissure, vasculature
But before that we need to
have a good understanding of
Normal Radiographic Anatomy
Left
Hemidiaphragm
Stomach gas
bubble
Splenic flexure of
the
the large intestines
Let’s look at some of
visual abdominal structures
Right
Hemidiaphragm
Liver
Let’s look at the Bony
thorax
Ribs
Spine
Clavicle
Scapula
Chest wall
Let’s look at
the Bony
thorax
Ribs
Spine
Clavicle
Scapula
Chest wall
Trachea
on CXR
Hilum
Let’s look at the normal
Mediastinal Structures
Superior
Vena
Cava
Ascending
Aorta
Right
Atrium
Inferior
Vena
Cava
Vessels
Aortic Arch
Pulmonary Artery
Left Atrium
Left Ventricle
Aortic
Knob/Arch
Descending
Aorta
Left
Atrium
Ascending
Aorta
Right
Ventricle
Left
Ventricle
Inferior Vena Cava
Lung Fields
Upper
Let’s look at the normal Lung
Structures
Middle
Lower
Retrosternal
Clear Space
Retrocardiac
Clear Space
Lateral
Costophrenic
Sulci
(Recesses,
Angles)
Cardiophrenic
Sulci
(Recesses,
Angles
Posterior
Costophrenic
Sulci
(Recesses,
Angles)
What are the Pulmonary
Fissures?

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They are the coming together of the visceral
pulmonary pleura.
Right lung
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Oblique (major) fissure
Horizontal (minor) fissure
Left Lung

Oblique (major) fissure
Right Oblique
Fissure
Horizontal
Fissure
Left
Oblique
Fissure
A closer
look at
the
fissures
RUL
LUL
RML
RLL
LLL
References

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Felson’s Principles of Chest Roentgenology: A
Programmed Test, 2nd Edition. Goodman, Lawrence R.;
W.B. Saunders Co., 1999.
Pocket Atlas of Radiographic Anatomy. Moller, TB et al.;
Thieme Medical Publishers, 1993
Clinical Imaging with Skeletal, Chest and Abdomen Pattern
Differentials, Dennis Marchiori, ed. (WN 180 M317c)