Basic Radiographic Principles
Basic Radiographic Principles
Basic Radiographic Principles
:Metal
Air (A) absorbs the least x-rays and appears blackest on conventional
radiographs. Fat (F) (represented by overlying breast tissue here) absorbs
more x-rays. Soft-tissue (ST), which is the same density as fluid on
conventional radiography absorbs the next most. Bones, which are
calcium density (C), absorb most of the x-rays.
Metal (black arrows) absorbs almost all x-ray and appears whitest on
conventional radiographs. There is no naturally occurring metal density in
the body visible on conventional radiography but metal artifacts (like
these snaps) or radiologic contrast material containing barium or iodine
(which also absorb almost all x-ray) are seen frequently.
Question2.Now you see it; now you dont. Why dont you see the heart of the
same infant in Fig. B taken two days after Fig. A?
: The air normally surrounding the heart has become the same
radiographic density as the heart.
The infants heart (H) is visible in the chest (Fig. A) because there is air in
the lungs (L) surrounding the soft tissue density of the heart and this
difference in radiographic densities allows for the identification of the
borders of the heart.
In Fig. B, the lungs no longer contain air and are therefore the same
radiographic density as the heart. We are no longer able to identify the
borders of the heart as being separate from the lungs. This is an
important sign in radiology (silhouette sign) and is discussed in Chapter
4 of the text.
Question 3. These are two views of the forearm on a 28-year-old male whose
physician palpated a mass (white arrows). Based on your knowledge of
radiographic densities, you can say what the physician palpated is most likely a:
: Lipoma
If you examine the radiographic densities carefully, you can see that
the mass is blacker (absorbs less x-ray) than the surrounding soft
tissue (ST) but not as black as air (A) in the room surrounding the
patient (it absorbs more x-ray than air).
The radiographic density that falls between air density and soft tissue
density in the amount of x-rays it absorbs is fat (F).
This mass (white arrows) was a lipoma of the forearm. This lesion was
benign and was easily excised.
Question 4 . This is a frontal radiograph of the legs of a 12-year-old female. The
arrows point to abnormal accumulation of what substance, based on its
radiographic density?
:Calcium or bone
This substance is less dense than metal (M) which is used as a shield for
the gonadal region on this radiograph and more dense than soft tissue
(ST), represented by muscle.
The white arrows point to calcium density (the same radiographic density
as bone), the whitestnaturally-occurring substance in the body,
absorbing most x-rays.
When the lateral view is obtained (Fig. 01-05B), it is evident that the bullet
is not inside the chest at all but lies subcutaneously in the soft tissues of
the patients back (white circle).
Question 6
This is a 72-year-old female with left-sided chest pain. The key finding on
this study involves the:
: soft tissues
It doesnt matter what system you use for reviewing imaging studies as
long as you look at everything on the images. But, if you dont know what
you are looking for, you still wont see the findings. There is an axiom in
radiology: You only see what you look for and you only look for
what you know. So, besides a system for viewing images, you need to
learn how to recognize normal and differentiate it from abnormal.
Question 7
There is an air-fluid level (air over fluid) in a large cavity in the left lung (black
arrows). In order to visualize an air-fluid level, which one of the
following must always occur?
:The xray beam must be oriented horizontally
Horizontal x-ray beams are usually parallel to the floor of the examining
room. Using conventional radiography, an air-fluid (black arrows) or fat-
fluid level will only be visible if the x-ray beam is horizontal, regardless of
the position of the patient.
Therefore, you will never see an air-fluid level no matter what the position
of the patient unless the conventional radiographic exposure is made
using a horizontal x-ray beam.
You dont have to specify whether you want the x-ray beam to be
horizontal or vertical when ordering a study; by convention certain studies
are always done using one method or the other. In general, any study with
the terms erect, cross-table or decubitus is always done with a
horizontal beam.
Question 8
This is a close-up of a lateral view of the knee obtained with the patient lying on
the examining table and the x-ray beam directed horizontally (parallel to the
floor) across the table. What abnormality does the black arrow point to?
: A fat over fluid level
The most common interface is air rising over fluid, as seen normally in the
bowel. Another much less common interface includes urine or bile rising
over calcium in suspension (milk of calcium)in the kidney or gallbladder.
Question 9
This is a lateral view of the skull in a 60-year-old male with lung cancer. The black
arrows point to multiple abnormalities. What terms best describe the nature of
the abnormalities?
:Lucent or lytic lesions
The black arrows point to multiple lucent lesions in the skull. They are less
dense (more lucent) than the surrounding normal skull. These lesions
could also be called lytic lesions as the normal bone has been destroyed.
These lesions are metastases to the bone from the patients lung cancer.
Lung, renal and thyroid carcinoma typically produce lytic, destructive
lesions in the bone.
Question 10
This is a contrast-enhanced axial CT image of the upper abdomen in a 78-year-
old man with colo-rectal carcinoma and multiple metastases to the liver (black
arrows point to some). What terms best describe the nature of the abnormalities?
: Areas of decreased attenuation or hypoattenuation
The black arrows point to multiple lesions which
are hypointense or hypoattenuating or havedecreased
attenuation relative to the surrounding normal liver. Their margins are
irregular and indistinct. This is a characteristic appearance for metastatic
disease to the liver.
Question 1
This is a frontal radiograph of a 62-year-old man. Which of these
statements best describes the technical quality of this radiograph?
: The radiograph is underpenetrated
In Fig. 02-01, the patients thoracic spine is not visible through the heart
which indicates that this image is underpenetrated. On a well-
penetrated chest radiograph, the spine should be faintly visible through
the heart.
Evaluation of the lateral radiograph of the chest, when available, will help
in avoiding those pitfalls.
Question 2
This is a frontal radiograph of a 57-year-old man. Which of these
statements best describes the technical quality of this radiograph?
: The patient has taken an inadequate inspiration
Only eight posterior ribs are visible above the diaphragm making this a
suboptimum inspiration.
A poor inspiratory effort will compress and crowd the lung markings,
especially at the bases of the lungs near the diaphragm (black arrow).
Question 3
This is a frontal radiograph of an 82-year-old woman. Which of these
statements best describes the technical quality of this radiograph?
: The patient is rotated
This patient is so rotated towards her right, the heart projects over the
right hemithorax (black arrow).
Significant rotation (the patient turns their body to one side or the other)
may alter the expected contours of the heart and great vessels, the hila
and hemidiaphragms. Even minor degrees of rotation can distort normal
anatomy.
Question 4
This is a frontal radiograph of a 51-year-old man. Which of these
statements best describes the technical quality of this radiograph?
Notice too that the clavicles appear nearly straight (black lines) instead of
their normal S-shape.
Apical lordotic images of the chest can display technical artifacts including
obscuration of the left hemidiaphragm, an unusual contour to the left
heart border and straightening of the clavicles.
Most apical lordotic images are unintentional and occur when ill patients
are semi-upright in the hospital bed or stretcher at the time of the
exposure.
Question 5
Rotation the medial ends of the clavicles (closed black arrows) should
fall equidistant between the closest spinous process (arrowhead)
Question 6
The study is also underpenetrated as the spine is not visible through the
heart (black arrow). This can spuriously obscure the left hemidiaphragm
and accentuate the lung markings.
Almost all standard chest radiographs today are produced using x-ray
machines that incorporate automatic exposure controls
called phototimers that terminate the exposure at a preset level
reducing the chances for under- or overpenetration.
Question 7
In this patient (Fig. 02-07A), the spinous process (arrowhead) lies closer to
the left clavicular head (black arrow) than the right (white arrow).
Therefore, this patient is rotated towards his own right.
Fig. 02-07B demonstrates another patient, this one rotated towards his
left. The spinous process (arrowhead) lies closer to the right clavicular
head (white arrow) than the left (black arrow).
Significant rotation may alter the expected contours of the heart and
great vessels, the hila and hemidiaphragms. Even minor degrees of
rotation can distort normal anatomy.
Question 8
Most apical lordotic images are unintentional and occur when ill patients
are semi-upright in their bed at the time of the exposure. The x-ray beam
is directed horizontally producing the same results as would occur if the
patient were completely upright and the beam was angled upwards
toward the head.
Question 9
Dont overlook the lateral chest radiograph. It can help you determine the
location of disease you already identified as being present on the frontal
image, as in this example, or it can confirm the presence of disease you
may be unsure of on the basis of the frontal image alone. Many times, it
can also demonstrate disease not visible on the frontal image.
Question 10
Fig. 02-10B is the frontal radiograph on this same patient and it shows a
large mediastinal soft tissue mass (white arrow) which is obscuring the
aorta and part of the heart.
Recognizing Cardiomegaly
Question 1
These are frontal and lateral radiographs of the chest on a 34-year-old female
with chest pain. Does she have cardiomegaly?
The widest internal diameter of the rib cage usually is found at the level of
the diaphragm.
On the lateral view (Fig. 03-01B), look at the space posterior to the heart
and anterior to the spine at the level of the diaphragm. In a normal
person, the cardiac silhouette will usually not extend posteriorly over the
spine. In this patient, it does (closed white arrow).
Question 2
This is a portable upright frontal chest radiograph in a 56- year-old man. Does
this patient have cardiomegaly?
When the same patient takes a good inspiration (Fig. 03-02B), we can see
the heart is not enlarged.
Question 3
This 48-year-old male has a murmur. Why does his heart appear slightly enlarged
on this study?
: He has a sternal deformity
Question 4
This is a newborn baby girl with respiratory distress. Is the heart enlarged?
In newborns and infants, the heart will normally appear larger, relative to
the size of the thorax, than it does in adults. Whereas a cardiothoracic
ratio of greater than 50% is considered abnormal in adults, the
cardiothoracic ratio may reach up to 65% in infants and still be normal.
In a child, the thymus gland may overlap portions of the heart and present
a confusing picture. The normal thymus gland has a somewhat lobulated
appearance, especially where it is indented by the ribs (black arrow).
Question 5
This is a 50-year-old man who has chronic renal failure and is undergoing
hemodialysis. The two images are taken 4 days apart. How can you explain the
rapid decrease in his apparent heart size?
In this patient, the second study (Fig. 03-05B) is a two posterior interspace
better inspiration (11 ribs-broken black arrow) than the first study (9 ribs-
closed black arrow). Such a change in inspiratory effort, though it may
seem minor, can produce a major change in the apparent size of the
heart, as it did in this case.
Recognizing Airspace vs. interstitial lung disease
Question 1
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Patient B has right lower lobe disease (broken black arrow) which is
fluffy and poorly marginated. It is difficult to tell with certainty
where the disease ends and normal lung begins. These are all
characteristics of airspace disease. Patient B had aspiration
pneumonia.
Question 3
You are shown an image from chest CTs on two different patients - A and B. Which
of the statements describes the patterns of lung disease on each of these two
scans?
Patient A has airspace disease but patient B has interstitial disease
Question 4
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Question 5
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Question 6
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Patient A has diffuse, fluffy and confluent disease with indistinct margins
(black circle), signs of airspace disease. The airspace disease has replaced
the air normally found in the lower lobes so that they are the same
density as the heart and diaphragm. Thus the edges of the heart and the
hemidiaphragms are not visible (silhouette sign). This patient had
pulmonary edema.
Question 7
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Patient A has interstitial disease but patient B has airspace disease
Patient A has a mass in the left upper lobe (white arrow). It is sharply
marginated and well-circumscribed. The demarcation between the mass
and normal lung is clear. It satisfies the criteria for an interstitial process.
This was a left upper lobe bronchogenic carcinoma which was an
adenocarcinoma in cell type.
Patient B has confluent airspace disease that occupies the whole upper
lobe on the right. It is homogeneous, lobar in distribution, sharply
demarcated only where it contacts the minor fissure (black arrow). There
are air bronchograms present (black circle). This was
aPneumococcal pneumonia.
Question 8
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Patient A has airspace disease but patient B has interstitial disease
Question 9
You are shown an image from chest CTs on two different patients - A and B. Which
of the statements describes the patterns of lung disease on each of these two
scans?
Patient A and Patient B both have interstitial disease
Question 10
You are shown frontal radiographs on two different patients - A and B. Which of
the statements describes the patterns of lung disease on each of these two
radiographs?
Patient A has interstitial disease but patient B has airspace disease
Patient B has a focal density in the right upper lobe with a fluffy
appearance, air bronchograms (black arrow) and indistinct margins (white
circle), all characteristic of airspace disease. This was
a Staphylococcal pneumonia.
Question 1
The patient is a 68-year-old male with recent weight loss. Which of these choices
best explains the findings on this frontal radiograph?
Atelectasis
Question 2
The patient is a 56-year-old man with shortness of breath. Which of these choices
best explains the findings on this frontal radiograph?
Pleural effusion
Question 3
The patient is a 49-year-old man with chronic cough. Which of these choices best
explains the findings on this frontal radiograph?
Post-pneumonectomy
This patient has previously undergone removal of the entire left lung for
carcinoma of the lung.
The trachea and heart gradually shift toward the side of opacification.
Eventually, fibrous tissue forms in the pneumonectomized hemithorax and
in most patients the entire hemithorax is opaque.
The heart (white arrow) and trachea (closed black arrow) shift toward the
side of opacification. The chest study looks identical to that of a patient
with atelectasis of the entire lung except for surgical removal of one or
more ribs and the presence of surgical clips (broken black arrow).
Question 4
The patient is a 28-year-old man with shortness of breath. Which of these choices
best explains the findings on this frontal radiograph?
Pneumonia
There is no shift of the heart (white arrow) or trachea (black arrow). There
may be air bronchograms present, as in this patient, (black circle)
identifying the disease as almost certainly being airspace in location.
Question 5
This is a newborn infant with difficulty breathing. Which of these choices best
explains the findings on this frontal radiograph?
Atelectasis
The tip of the endotracheal tube (solid black arrow) projects below the
carina into the bronchus intermedius on the right. Only the right middle
and lower lobes are being aerated. The endotracheal tube delivers no air
to the entire left lung or the right upper lobe. The air that had been
present in that part of the lung has been reabsorbed and atelectasis is
present.
There is a shift of the mobile structures towards the atelectasis. The minor
fissure shifts upward (solid white arrow) while the heart shifts towards the
left. The right heart border is superimposed on the spine (broken white
arrow) due to the leftward movement of the heart.
Within hours after the tip of the endotracheal tube is withdrawn, the lungs
will be fully re-expanded.
Question 6
The patient is 68-year-old with shortness of breath. Which of the following studies
would provide theleast additional information in this patient?
Right lateral decubitus view of the chest
Decubitus views of the chest in patients with pleural effusions are usually
done for one of two reasons: (1) to establish if the fluid is free-flowing in
the pleural space (which has implications for its successful drainage), or,
on occasion, (2) to visualize the underlying lung if the patient lies on the
side opposite from the pleural fluid for the radiograph.
If, as in this case, the entire hemithorax is filled with fluid (black arrow),
neither of those goals can be achieved. The fluid will have no place to
flow and the lung will be no more visible no matter how the patient
turns.
Decubitus views of the chest are usually of no diagnostic value when the
entire hemithorax is opaque because of a large pleural effusion.
Question 7
The patient is a 51-year-old female with chest pain. Which of these choices best
explains the findings on this frontal radiograph?
Post-pneumonectomy
This patient had previously undergone removal of the entire right lung
(pneumonectomy) for a bronchogenic carcinoma.
Most times, either the 5 or 6 rib is removed at the time of surgery (black
th th
arrow). Occasionally, enough of the periosteum of the rib remains that the
rib partially regenerates over time, but it always appears smaller and
more irregular than normal ribs.
Question 8
The huge effusion (open black arrow) pushes the heart (closed black
arrow) across the midline further to the left. This image is below the level
of the trachea but it, too, would have been displaced to the left by the size
of this effusion.
This patient had a primary lung malignancy, not seen on this imaging,
that was producing the effusion.
Question 9
The patient is a 53-year-old female with hemoptysis. Which of these choices best
explains the findings on this frontal radiograph?
Atelectasis
This patient has had no prior lung surgery, but did you notice that she had
undergone another type of surgery
There is a shift of the heart and trachea toward the side of opacification
indicating volume loss on the right side. Careful observation of the right
and left main bronchi reveals a sharp cut-off on the right side (closed
black arrow) and a normal appearing left side (dotted black arrow).
Question 10
The patient is a 69-year-old male with recent weight loss and hemoptysis. Which
of these choices best explains the findings on this frontal radiograph?
Both atelectasis and effusion combined
Notice there is no shift of the heart (white arrow) or trachea (black arrow),
nor are there any air bronchograms present to indicate pneumonia.
This patient had a squamous cell carcinoma of the right main bronchus
with pleural metastases and a large effusion.
Recognizing Atelectasis
Question 1
These are frontal and lateral chest radiographs on a 57- year-old man with cough.
What type of atelectasis is this?
Obstructive atelectasis
There is left upper lobe atelectasis present. The dotted black arrow points
to an increased soft tissue density in the left hilum (A). There is hazy
opacification of the left upper lobe (open black arrows) because most of
the air has been resorbed from that lobe secondary to a centrally
obstructing lesion.
On the lateral view (B), the major fissure (black arrows) is pulled forward
and there is increased density in the partially atelectatic left upper lobe
(open arrow).
Question 2
This is an axial CT scan of the lower chest in a 61-year-old who is short of breath.
What type of atelectasis is this?
Compressive atelectasis
There are large bilateral pleural effusions present (white arrows). Markedly
compressed by the large right effusion is the right lower lobe (black
arrows).
In this patient, the large effusions are bilateral and the cause of the fluid
was congestive heart failure.
Question 3
This is a close-up of the right lower lobe of a 32-year-old female with tachypnea.
What type of atelectasis is this?
Sub-segmental atelectasis
Question 4
Question 5
This is the right lung in a 58-year-old female with weight loss. The most likely
cause of her right upper lobe atelectasis is:
An obstructing bronchogenic carcinoma
The closed white arrow points to a mass in the right hilum associated with
atelectasis of the right upper lobe as demonstrated by opacification of the
upper lobe and elevation of the minor fissure (open white arrow) from
volume loss.
This patient had a squamous cell carcinoma of the right upper lobe
bronchus and was already receiving chemotherapy (note indwelling
central line)
Question 6
This is a frontal radiograph of the chest on a 55-year-old male with
cough. The image reveals:
Left lower lobe atelectasis
This patient had a mucus plug that was extracted via bronchoscopy.
Question 7
(open arrow).
Question 8
There is a shift of the heart (open white arrow) and trachea (open black
arrow) toward the side of opacification indicating volume loss on the right
side. Careful observation of the right and left main bronchi reveals a sharp
cut-off on the right side (dotted black arrow) and a normal appearing left
side.
Did you notice that this patient had undergone prior surgery?
Question 9
This is a frontal chest radiograph on a 68-year-old in the critical care unit. His left
lung atelectasis is due to:
A complication of his treatment
If the tip of an endotracheal tube enters the right main bronchus, only the
right lung tends to be aerated and remain expanded.
Once the tip of the endotracheal tube is withdrawn above the carina, the
atelectasis usually clears very rapidly.
Question 10
There are bilateral, linear densities at the lung bases (white arrows)
representing sub-segmental atelectasis.
The cause of this patients splinting is seen in the free air beneath the
right hemidiaphragm (black arrow). This patient is two days post-op
abdominal surgery. Sub-segmental atelectasis is common in patients who
are splinting from recent surgery.
Question 1
Because of the natural elastic recoil of the lungs, pleural fluid appears to
rise higher along the lateral margin of the thorax than it does medially in
the upright frontal projection. This produces a characteristic meniscus or
U shape to the effusion.
Question 2
Did you notice why this patient may have the pleural effusion? Carefully
examine the chest for symmetry and you may notice that, although the
left breast shadow is present (open black arrow), there is no right breast
visible. Furthermore, there are numerous surgical clips (broken black
arrow) in the right axilla.
Question 3
This is an axial image displayed using the mediastinal window from a contrast-
enhanced CT scan of the chest in a 27-year-old male who had been stabbed.
Which of the following is false, based on the image supplied?
There is a unilateral left pleural effusion
By convention, chest CT scans are viewed with the patients right on your
left and the patients left on your right. In the supine position, as most are
usually scanned, the top of the image is anterior and the bottom is
posterior.
Question 4
This is a 78-year-old female with chest pain. This radiograph demonstrates the
typical appearance of which of the following:
Scarring at the costophrenic sulcus
Pleural thickening, unlike most effusions, will not change in location with a
change in patient position.
This patient had chest trauma many years earlier and most likely had a
hemothorax at the time that led to this scarring and pleural thickening.
Question 5
This is a close-up view of the right lower lung field in a 53-year-old man. Which
one of the following is correct?
There is a right pleural effusion
Air in the lung should extend to the inner surface of each rib as shown in
the close-up view (Fig. 07-05B) of a normal patients right costophrenic
sulcus (open white arrows).
In the patient shown in Fig. 07-05A, the air in the lung extends only to the
inner margin of a dense white band that represents a collection of fluid
between the visceral and parietal pleura, i.e. a pleural effusion (closed
black arrows).
Question 6
This is a 39-year-old female with chronic renal disease. What type of pleural
effusion is demonstrated in this frontal and lateral radiograph?
A subpulmonic effusion
As all pleural effusions, this type collects between the visceral and parietal
pleura, but a subpulmonic effusion is located beneath the lung.
On the frontal view, the highest part of the apparent right hemidiaphragm
is displaced laterally (closed black arrow). This is called the apparent
hemidiaphragm because it really represents the interface between the
effusion and the lung, not the diaphragm and the lung. The diaphragm is
obscured by the fluid atop it.
On the lateral view, the fluid appears to change direction between the
anterior portion (open black arrow) and the posterior portion (closed white
arrow) where it meets the major fissure (broken black arrow), a typical
appearance of a subpulmonic effusion
Question 7
This is a 3-month-old child who has a high fever and cough. Why do you think the
right-sided pleural effusion has this appearance?
The effusion is loculated
In the upright position, pleural fluid should fall to the most dependent
location the base of the hemithorax. This pleural fluid maintains its
position along the lateral chest wall (broken black arrows) in apparent
defiance to gravity.
Question 8
These are two chest radiographs taken on the same person 15 minutes apart.
What information provided on the images best explains the apparent
improvement in the appearance of the right pleural effusion on the later study?
The patients position has changed between the two studies
The patient was supine for the image at 11:00 am and was sitting upright
for the image done 15 minutes later (see arrows). There has been no
change in the size of the effusion between the two images, only the
position of the fluid due to a change in the patients position.
This can be confusing when trying to assess serial changes in the size of
an effusion. Ideally, each portable chest radiograph should be exposed
with the patient in the same position so as to make comparison more
reliable.
Question 9
After a right-sided thoracentesis is performed, you are asked to review the post-
thoracentesis radiograph. What are your findings?
There is a small right effusion remaining and there is a pneumothorax
Most of the fluid had been removed and the post-thoracentesis study was
performed with the patient upright (closed black arrow points to air-fluid
level in the stomach). There is an interface between air and fluid in the
right hemithorax as manifest by a straight edge which the remaining
pleural fluid forms with air in the pleural space (open black arrows).
This small pneumothorax resorbed without the need for a chest tube.
Question 10
These are three images of the same patient taken in different positions. Look at
all three images and then decide which of these statements is correct:
There are bilateral pleural effusions and they are free-flowin
For a left lateral decubitus view of the chest (B) the patient is lying with
their left side down and the fluid is seen to flow freely along the left chest
wall (closed black arrows).
For a right lateral decubitus view of the chest (C), the patient is lying with
their right side down, and the fluid is seen to flow freely along the right
chest wall (dotted black arrows).
Recognizing pneumonia
Question 1
The patient is a 39-year-old woman with pneumonia. Based on the frontal chest
radiograph, the pneumonia is in the:
Right middle lobe
In Figs. 08-01A and B, the closed black arrow points to the sharp border of
the minor fissure, below which is the consolidated middle lobe. Since the
middle lobe is not in contact with the right hemidiaphragm, the
hemidiaphragm remains visible (dotted black arrow).
Not well seen on the frontal view, but visible on the lateral, is pneumonia
in the left lower lobe recognized by the spine sign (white arrow) in Fig.
08-01B.
Question 2
The patient is a 17-year-old male with pneumonia. Based on the frontal chest
radiograph, the pneumonia is in the:
Right upper lobe
The right upper lobe is in contact with the ascending portion of the aorta,
so that when inflammatory exudate fills the upper lobe and renders it the
same radiographic density as the aorta, the border between the lung and
aorta disappear (open black arrow).
Question 3
The patient is a 19-year-old male with pneumonia. Based on the frontal chest
radiograph, the pneumonia is in the:
Right lower lobe
On the frontal view (Fig. 08-03A), there is consolidation of the right lower
lobe. The closed white arrow points to the major fissure, seen here only
because the lower lobe is consolidated. The pneumonia contacts, and
therefore silhouettes, the right hemidiaphragm (open black arrow), which
is classic for lower lobe pneumonia. The right heart border is not in
contact with the lower lobe and is thus still visible (closed black arrow).
Question 4
The patient is a 43-year-old male with pneumonia. Based on the frontal chest
radiograph, the pneumonia is in the:
Lingula of the left upper lobe
The lingula is the analog of the right middle lobe on the left, but the
lingula is part of the left upper lobe and is not a separate lobe.
The lingula extends to the level of the diaphragm and is located anteriorly.
In Fig. 08-04A, the left heart border is being silhouetted (obscured) by the
consolidated lung in contact with it, obliterating the border normally
visible between the heart and the lung (open black arrow).
The upper lobe is bound posteriorly by the major fissure. In Fig. 08-04B,
the sharply marginated posterior border of this pneumonia (white arrow)
is produced by the major fissure.
Question 5
The patient is a 31-year-old male with pneumonia. Based on the frontal chest
radiograph, the pneumonia is in the:
Right lower lobe
This is a tricky one, but only a pneumonia in the superior segment of the
lower lobe can seem to extend both above and below the minor fissure
(Fig. 08-05A dotted black arrows) on the frontal image without
interruption.
Fig. 08-05B is the lateral view of this patient. The dotted black line is the
location of the minor fissure. On a frontal view, you can see how this
pneumonia (solid black arrows) would project both above and below the
fissure.
The upper lobe is bound inferiorly by the minor fissure and the middle
lobe is bound superiorly by the minor fissure. Pneumonia in either one of
those lobes would stop abruptly at the minor fissure. The fissures are
quite resistant to direct extension of disease.
Question 6
The patient is a 61-year-old male with pneumonia. Based on the frontal chest
radiograph, the pneumonia is in the:
Left lower lobe
On the lateral view (Fig. 08-06B), the lower portion of the thoracic spine
appears to become whiter (closed black arrow) instead of darker, as it
normally should. This is because the lower lobe pneumonia is
superimposed on the spine, adding to its density on the lateral
radiograph. This increased density of the lower thoracic spine due to
disease in the lung is called the spine sign.
Question 7
This is a 47-year-old male with cough and fever. From the appearance of this
disease, which organism would be the most likely etiologic agent?
Tuberculosis
Question 8
This is a 28-year-old male with fever. From the appearance of this disease, which
organism would be the most likely etiologic agent?
Pneumocystis pneumonia (PCP)
It can also present as airspace disease that may mimic the central
distribution of pulmonary edema, as unilateral airspace disease, or
widespread, patchy airspace disease.
Question 9
This is one image from a CT scan of the chest on a 31-year- old female with
cough and fever. From the appearance of this disease, which organism would be
the most likely etiologic agent?
Pneumococcal pneumonia
In its most classical form, as is shown in this case, the disease fills most or
all of a lobe of the lung, in this case the right upper lobe. Since the upper
lobe is bound posteriorly by the major fissure, the posterior margin of this
pneumonia (white arrow) is sharply marginated.
Question 10
This is a 43-year-old male with hemoptysis. From the appearance of this disease,
which organism would be the most likely etiologic agent?
Aspergillosis (aspergilloma)
Fig. 08-10A shows a fungus ball (white arrow) that has formed inside of a
pre-existing tuberculous cavity (open white arrow). The patient is supine
and the fungus ball falls to the dependent side of the cavity, which is the
posterior wall.
In Fig. 08-10B, the same patient is scanned prone. Note how the fungus
ball (white arrow) falls to the dependent side of the cavity (now the
anterior wall). A tumor would remain in the same location in the cavity no
matter what the position of the patient.
Pneumothorax
Question 1
This is a close-up view of the right upper lung field. Does this person have a
pneumothorax?
No, this patient has a skin fold and not a pneumothorax
The black arrow points to a skin fold, not the pleural white line of a
pneumothorax. Skin folds are typically thick white edges not thin white
lines. They usually occur in patients who have lost a considerable amount
of weight.
Figure 09-01B shows the same patient repositioned for another chest
radiograph moments later. The skin fold has disappeared.
Question 2
This is a close-up view of the right upper lung field. Does this person have a
pneumothorax?
No, this patient has an accessory fissure and not a pneumothorax
The black arrow points to a thin white line which represents an enfold of
pleura forming an accessory fissure of the lung.
This is a pneumothorax.
The black arrows point to the visceral pleural line, the structure which
must be identified for an accurate diagnosis of pneumothorax. Notice how
the visceral pleural line parallels the curvature of the chest wall.
Question 4
Unlike the visceral pleural line of a pneumothorax, the edge of a bulla will
almost always curve inward, away from the thoracic wall (thick black
arrow).
This is a close-up view of the right upper lung field. Does this person have a
pneumothorax?
The medial border of the scapula (white arrow) does not usually parallel
the curvature of the chest wall, as a pneumothorax does. The lung distal
to the medial border of the scapula will be denser than normal lung (black
arrow) because of the overlying density of the scapula whereas the lung
distal to a pneumothorax is usually more lucent than the normally aerated
lung.
Make sure you identify the location of the medial border of the scapula
before deciding a patient has a pneumothorax. If you are having trouble
deciding between a pneumothorax and the scapula, look at the patients
opposite side a patient will have two scapulae much more often than
two pneumothoraces.
Question 6
This is a close-up view of the right lower lung field. Does this person have a
pneumothorax.
This is a pneumothorax.
The black arrow points to the visceral pleural line, the structure which
must be identified for an accurate diagnosis of pneumothorax. Notice how
the visceral pleural line parallels the curvature of the chest wall.
The white arrow points to the relative lucency of the peripheral lung due
in part to the absence of any blood vessel markings in the pneumothorax
itself.
Question 7
This is a close-up view of the right upper lobe. Does this patient have a
pneumothorax?
No, this patient has bullous disease and not a pneumothorax
Question 8
This is a close-up view of the right lower lung field. The dense white wire
traversing the chest is a cardiac monitor lead. Does this patient have a
pneumothorax?
No, this patient has a skin fold and not a pneumothorax
The thickness of the edge (black arrow) should tell you this can not be the
visceral pleural white line. In addition, there are lung markings seen distal
to the edge (white arrow). There are usually no lung markings seen distal
to the pleural white line of a pneumothorax.
Skin folds almost always occur when the patient is lying on their back at
the time of the exposure, as they would for a supine portable chest
radiograph.
Question 9
This patient had penetrating trauma and was short of breath at the time of this
study. Does this patient have a pneumothorax?
Yes, this patient has a pneumothorax
In addition, notice how the heart is displaced farther to the right than
normal (open black arrow) indicating that the air in the pleural space is
under tension.
Question 10
This is a close-up view of the right upper lung field. There are two linear densities
visible on this image. Which of the combinations available to choose from is
shown on this image? (The Hint photo may help.)
Pneumothorax and the overlying scapula
This is tricky because there are two linear densities representing both a
pneumothorax and the medial border of the scapula.
The pneumothorax produces the pleural white line (thin black arrows) that
parallels the contour of the chest wall.
The medial border of the scapula (thick black arrows) has a similar
contour to the pneumothorax but is composed of a thicker cortical edge
than a pneumothorax. There is a crescent of increased density (white
arrow) because of the overlapping scapula.
The Hint photo shows that the same density of the medial border of the
scapula is present on both the left and right.
Recognizing diseases of the Chest
Question 1
The patient is a 27-year-old with dysphagia. What is the most likely diagnosis?
The lower pole of either lobe of the thyroid may enlarge and project
downward into the upper thorax, rather than anteriorly into the neck.
Radioisotope thyroid scans are the study of first choice in confirming the
diagnosis of a substernal thyroid as virtually all of them will display some
uptake of the radioactive tracer.
Question 2
This 23-year-old male had weight loss. What is the most likely diagnosis?
Lymphadenopathy
This is a 79-year-old man with chest pain. What is the most likely diagnosis
Aortic aneurysm
This image is at the level of the aortic arch. The ascending aorta (AA) is
slightly enlarged, but the descending aorta (DA) is markedly enlarged and
contains considerable thrombus (double black arrow). Aneurysms are
defined as enlargement of a vessel greater than 50% of its original size.
The patient is a 43-year-old with multiple skin nodules. What is the most likely
diagnosis?
Neurofibromatosis
This is neurofibromatosis and the lesion (white arrow) is growing from the
spinal nerve and destroying the left posterior half of the vertebral body
(black arrow).
Question 5
This is a 78-year-old man with a cough. The most likely diagnosis is:
Bronchogenic carcinoma
Question 6
There is a 1.2 cm nodule in the right upper lobe (black arrow). This was a
hamartoma of the lung.
Question 7
There are innumerable nodules in both lungs. Multiple nodules in the lung
are most often metastatic lesions that have traveled through the
bloodstream from a distant primary by hematogenous spread.
Question 8
How might you identify this 78-year-old man when you went into your waiting
room?
He might have ptosis on the right
there is a soft tissue mass (M) at the apex of the right lung. Just as
important, if you compare the ribs on the two sides, the left upper ribs
(white arrow) are normal, whereas there is destruction of the upper ribs on
the right (black arrow).
Question 9
Which cell type is this presentation of bronchogenic carcinoma most likely to be?
Adenocarcinoma
There is a mass in the left upper lobe (dotted arrow) with ipsilateral
enlargement of the left hilum (solid arrow).
Question 10
Which cell type is this presentation of bronchogenic carcinoma most likely to be?
Squamous cell carcinoma
There is a central mass in the right hilum (solid arrow) that is obstructing
the right upper lobe bronchus and producing right upper lobe atelectasis
(dotted arrow points to the minor fissure which has been pulled upwards
by the loss of volume in the right upper lobe).