How to Interpret a Chest X-Ray (Lesson 7 - Diffuse Lung Processes)
Summary
TLDRThis educational video delves into the interpretation of chest X-rays, focusing on diffuse lung diseases. It outlines objectives to identify lung volume issues, differentiate pulmonary edema types, classify interstitial processes, and compare alveolar and interstitial findings. The script explains the signs of reduced and increased lung volumes, discusses alveolar opacities, including cardiogenic and non-cardiogenic edema, and explores interstitial opacities' subtypes. It concludes with distinguishing features between alveolar and interstitial patterns, providing a foundation for diagnosing various lung conditions.
Takeaways
- đ The video is part of a series on interpreting chest X-rays, focusing on diffuse lung disease.
- đ The learning objectives include identifying reduced lung volumes, distinguishing cardiogenic from non-cardiogenic pulmonary edema, classifying interstitial processes, and comparing alveolar and interstitial findings.
- đ„ Reduced lung volumes on an X-ray can indicate underlying lung, diaphragm, neuromuscular, or thoracic wall disease, and should not be mislabeled as 'poor inspiratory effort' without direct observation.
- đ Hyperinflation on X-ray is characterized by an increased subjective impression of total lung capacity, often seen in COPD and occasionally in asthma during acute exacerbations.
- đ« Alveolar opacities are due to fluid accumulation in the alveoli and terminal bronchioles, and can be caused by edema, pus, or blood.
- đ§ The differential diagnosis for alveolar opacities includes cardiogenic and non-cardiogenic pulmonary edema, with the latter associated with conditions like acute lung injury and ARDS.
- đŹ Radiographic features to differentiate cardiogenic from non-cardiogenic edema include air bronchograms, peribronchial cuffing, curly lines, cephalization, and the batwing pattern.
- đŹ Interstitial opacities can present as reticular (excessive lines), nodular (excessive dots or nodules), or reticular nodular patterns on X-rays.
- đ„ The differential diagnosis for interstitial opacities is extensive, including conditions like pulmonary fibrosis, connective tissue disease, and sarcoidosis.
- đ Alveolar opacities can change rapidly and may contain air bronchograms if due to non-cardiogenic edema, while interstitial opacities evolve more slowly and have sharper margins.
- đ The next video in the series will cover focal lung processes, providing further insights into lung disease identification.
Q & A
What is the main topic of the seventh video in the series on interpreting chest x-rays?
-The main topic of the seventh video is diffuse lung disease.
What are the two primary learning objectives related to lung volumes mentioned in the script?
-The two primary learning objectives are to identify and know the differential diagnosis of low lung volumes and hyperinflation, and to describe them specifically without mislabeling them as poor inspiratory effort.
Why is it important to avoid labeling a chest x-ray with reduced lung volumes as 'poor inspiratory effort'?
-It is important because unless the interpreter is physically present when the x-ray was taken, they cannot know the patient's actual inspiratory effort. Mislabeling risks missing an early diagnosis of lung, diaphragm, neuromuscular apparatus, or thoracic wall diseases.
What is the most common etiology of reduced lung volume according to the script?
-The most common etiology of reduced lung volume may in fact be poor inspiratory effort, but it could also be due to a sub-optimally timed exposure or restrictive lung disease.
What does the term 'hyperinflation' on an x-ray refer to?
-Hyperinflation refers to a subjective impression that the total lung capacity is likely increased, based on the number of ribs seen, flattening of the diaphragms, and the diffusely increased lucency of the lungs.
What are the two classic radiographic categories of diffuse lung capacities discussed in the video?
-The two classic radiographic categories are alveolar opacities, often referred to as airspace opacities, and interstitial opacities.
How can one differentiate cardiogenic from non-cardiogenic pulmonary edema on an x-ray?
-One can differentiate them by looking for five radiographic features: air bronchogram, peribronchial cuffing, curly lines, cephalization, and the bat swing pattern.
What does the term 'cephalization' refer to in the context of pulmonary edema on an x-ray?
-Cephalization refers to the increased visibility of pulmonary vessels at the lung apices compared to the bases, which is suggestive of increased left atrial pressure.
What are the two main subtypes of alveolar opacities based on their differential diagnosis?
-The two main subtypes are cardiogenic pulmonary edema, associated with elevated pulmonary capillary wedge pressure, and non-cardiogenic pulmonary edema, where the wedge pressure is normal.
What is the significance of the bat wing pattern in differentiating cardiogenic from non-cardiogenic pulmonary edema?
-The bat wing pattern is most consistent with cardiogenic edema, though it may be seen with some specific aetiologies of non-cardiogenic edema, and it refers to bilateral, predominantly higher concentration of opacification.
How do alveolar and interstitial opacities differ in terms of their appearance and progression on an x-ray?
-Alveolar opacities have hazy margins, may contain air bronchograms if caused by non-cardiogenic pulmonary edema, and can change rapidly over time. Interstitial opacities have sharp margins, do not contain air bronchograms, and evolve more slowly.
What are some examples of diseases that can cause both alveolar and interstitial changes on an x-ray?
-Diseases such as pulmonary edema and sarcoidosis can cause both alveolar and interstitial changes, demonstrating the complexity of distinguishing between the two categories.
What is the differential diagnosis for diffuse interstitial opacities that cause a predominantly reticular pattern?
-Diseases that cause a predominantly reticular pattern include idiopathic pulmonary fibrosis, connective tissue disease, atypical pneumonia, asbestosis, chronic aspiration, pulmonary drug toxicity, sarcoidosis, and others.
How does the presence of nodules in interstitial opacities help differentiate between various lung diseases?
-The size of the nodules can help differentiate; diseases causing small nodules under two centimeters include miliary tuberculosis, fungal infections, silicosis, and sarcoidosis, while those causing medium and large nodules include metastatic cancer, lymphoma, and rheumatoid nodules.
What does the script mention as a common manifestation of sarcoidosis in the lung?
-Sarcoidosis can manifest in various ways in the lung, including causing either reticular or nodular interstitial patterns, alveolar opacities, and is best known radiographically as a cause of prominent hilar lymphadenopathy.
What is the final topic covered in the script before concluding the video?
-The final topic covered is a summary of the comparison between alveolar and interstitial opacities, highlighting their differences in terms of distribution, margin clarity, presence of air bronchograms, rate of change, and descriptive terms.
Outlines
đ Introduction to Diffuse Lung Disease in Chest X-rays
This paragraph introduces the seventh video in a series focused on interpreting chest X-rays, specifically addressing diffuse lung disease. The learning objectives include identifying and differentiating lung volumes and hyperinflation, recognizing pulmonary edema, distinguishing between cardiogenic and non-cardiogenic causes, classifying interstitial processes, and comparing alveolar and interstitial findings. The speaker emphasizes the importance of accurately identifying reduced lung volumes, avoiding mislabeling due to poor inspiratory effort, and recognizing the potential early signs of lung disease. The paragraph also touches on hyperinflation, its subjective nature, and its common association with COPD and asthma.
đ Differentiating Cardiogenic and Non-Cardiogenic Pulmonary Edema
The second paragraph delves into the differentiation between cardiogenic and non-cardiogenic pulmonary edema. It outlines the causes of cardiogenic edema, such as heart failure and various cardiac conditions, and non-cardiogenic edema, which is associated with conditions like severe sepsis and pneumonia. The speaker discusses five radiographic features that aid in this differentiation: air bronchogram, peribronchial cuffing, curly lines, cephalization, and the bat-wing pattern. Each feature is explained with examples and its significance in identifying the type of pulmonary edema is highlighted.
đ Understanding Alveolar and Interstitial Opacities
This paragraph discusses alveolar and interstitial opacities in the context of diffuse lung disease. Alveolar opacities result from fluid accumulation and can be caused by edema, pus, or blood. The paragraph differentiates between cardiogenic and non-cardiogenic causes of alveolar opacities and mentions additional causes such as multilobar pneumonia and diffuse alveolar hemorrhage. Interstitial opacities are then introduced, with subtypes including reticular, nodular, and reticulonodular patterns. The speaker provides examples of diseases that cause these patterns and notes the difficulty in distinguishing between them on plain radiographs.
đ Comparing Alveolar and Interstitial Opacities
The final paragraph provides a comparative summary of alveolar and interstitial opacities. It contrasts their distribution, margins, presence of air bronchograms, rate of change, and descriptive terms. Alveolar opacities are described as having a hazy margin, rapid change, and subjective descriptions, while interstitial opacities have a sharp margin, evolve slowly, and are described with more objective terms. The paragraph concludes with a preview of the next video in the series, which will cover focal lung processes.
Mindmap
Keywords
đĄDiffuse lung disease
đĄLung volumes
đĄPulmonary edema
đĄCardiogenic
đĄNon-cardiogenic
đĄInterstitial processes
đĄAlveolar opacities
đĄAir Bronchogram
đĄCephalization
đĄBatwing pattern
đĄReticular opacities
đĄNodular opacities
đĄSarcoidosis
Highlights
Seventh video in a series on interpreting chest x-rays with a focus on diffuse lung disease.
Learning objectives include identifying differential diagnosis of lung volumes and hyperinflation, distinguishing cardiogenic from non-cardiogenic pulmonary edema, classifying interstitial processes, and comparing findings in alveolar and interstitial processes.
Importance of accurately describing reduced lung volumes to avoid mislabeling and missing early diagnosis opportunities.
Common etiology of reduced lung volume includes poor inspiratory effort and restrictive lung disease.
Hyperinflation is less common on x-ray, indicated by increased total lung capacity and subjective impression.
Hyperinflation commonly seen in COPD and occasionally in asthma during acute exacerbations.
Radiographic categories of diffuse lung capacities include alveolar opacities and interstitial opacities.
Difficulty in distinguishing alveolar and interstitial opacities due to subjectivity and experience required.
Alveolar opacities result from fluid accumulation within alveoli and terminal bronchioles, such as edema, pus, or blood.
Cardiogenic pulmonary edema associated with elevated pulmonary capillary wedge pressure and left-sided heart pressures.
Non-cardiogenic pulmonary edema with normal wedge pressure, related to acute lung injury and ARDS.
Five radiographic features to differentiate cardiogenic from non-cardiogenic edema: air bronchograms, peribronchial cuffing, curly lines, cephalization, and batwing pattern.
Cephalization suggests increased left atrial pressure but is subjective and has poor interobserver agreement.
Batwing pattern consistent with cardiogenic edema but may also be seen with specific non-cardiogenic edema ideologies.
Diseases causing diffuse alveolar opacities without edema include multifocal pneumonia and diffuse alveolar hemorrhage.
Interstitial opacities categorized into reticular, nodular, and reticular nodular patterns based on radiographic appearance.
Difficulties in diagnosing diffuse interstitial opacities due to a large differential diagnosis and lack of distinguishing features on plain radiographs.
Sarcoidosis manifests in various lung patterns, including reticular, nodular, and alveolar opacities, and is known for prominent hilar lymphadenopathy.
Comparison between alveolar and interstitial opacities in terms of distribution, margin clarity, presence of air bronchograms, rate of change, and descriptive terms.
Upcoming video in the series will cover focal lung processes.
Transcripts
this is the seventh video in this series
on interpreting chest x-rays and the
topic is diffuse lung disease the
learning objectives are first to be able
to identify and know the differential
diagnosis of Load lung volumes and
hyperinflation second to be able to
identify pulmonary edema as well as
specific features that can help
distinguish cardiogenic from non
cardiogenic ideologies third to be able
to classify interstitial processes based
on their radiographic features and
finally to be able to compare typical
findings in alveolar and interstitial
processes the first topic in this video
will be a very brief discussion of lung
volumes so here is an x-ray which shows
an example of reduced lung volumes we
know this because when we count ribs
there are only seven full posterior ribs
seen above the diaphragm where normally
there should be nine to ten when
describing an x-ray with reduced lung
volumes it is important to describe it
specifically as such and never as quote
poor inspiratory effort which is
frequently done the reason for this is
that as the x-ray interpreter unless you
are physically present when the x-ray
was taken you have no idea what the
patient's inspiratory effort was like
low lung volumes may be the first sign
of otherwise occult disease of the lung
interstitial of the diaphragms
neuromuscular apparatus or thoracic wall
mislabeling this x-ray as poor
inspiratory effort risks missing an
opportunity at an early diagnosis of
these conditions having said that the
most common etiology of reduced lung
volume may in fact be poor inspiratory
effort it may also be the consequence of
a sub-optimally timed exposure it can
obviously be seen in restrictive lung
disease due to any of the aforementioned
general mechanisms and finally it can be
the consequence of unappreciated
subharmonic effusions which were
discussed in the last
video in this series in contrast to low
lung volumes we can instead see
hyperinflation which in my experience is
less common
there is no widely applied precise
definition of hyperinflation on x-ray
instead the term refers to a subjective
impression that the total lung capacity
is likely increased if measured by
pulmonary function tests this subjective
impression is based upon the number of
ribs seen flattening of the diaphragms
and the diffusely increased lucency of
the lungs hyperinflation has a very
short and specific differential
diagnosis it is most commonly seen in
COPD it can also occur occasionally in
asthma but only during acute
exacerbations for the remainder of this
video I'll be referring to the two
classic radiographic categories of
diffused lung capacities they are
alveolar opacities often referred to as
airspace capacities and interstitial
opacities while I will be discussing the
features which distinguish one category
from another and discussing the subtypes
of each in practice the distinction
between alveolar and interstitial
opacities is not easy it is a skill that
entails much subjectivity requires much
experience and typically shows
significant interrelation a large part
of these issues stems from the fact that
few diffused lung diseases are
completely limited to only the air
spaces or to the interstitial many
diseases which are classically alveolar
such as pulmonary edema may also
demonstrate typical interstitial changes
and many diseases which are classically
interstitial such as sarcoidosis may
also demonstrate typical alveolar
changes as a consequence many of the
distinctions discussed during the rest
of this video are not always obvious and
they may be a source of disagreement
even between experienced healthcare
professionals
alveolar opacities are due to fluid
accumulation within the alveoli and
terminal bronchioles this fluid may be
edema pus or blood opacities are hazy
with poorly defined margins but can
respect low bar boundaries unless
diffuse differential diagnosis for most
alveolar opacities can be divided into
two main subtypes first is cardiogenic
pulmonary edema which is that associated
with an elevated pulmonary capillary
wedge pressure which is a surrogate for
elevated left-sided heart pressures in
general this type of pulmonary edema can
be seen in any cause of congestive heart
failure this includes exacerbations of
long-standing cardiomyopathy acute MI
arrhythmia myocarditis or acute aortic
or mitral regurgitation secondary to
endocarditis then there is non
cardiogenic pulmonary edema in which the
wedge pressure is normal the clinical
correlate to diffuse non cardiogenic
pulmonary edema is the spectrum between
acute lung injury and acute respiratory
distress syndrome the distinction
between these two is largely arbitrary
and is based on the severity of a
patient's hypoxemia as with heart
failure a li and ARDS are not ideologies
themselves but can be caused by a long
and diverse list of pathologic
conditions these include severe sepsis
pneumonia including viral pneumonia from
things like influenza aspiration
pneumonitis pancreatitis severe burns
post transfusion reaction near-drowning
extreme elevation CNS catastrophe and
inhalational injury
in order to differentiate cardiogenic
from non cardiogenic edema on x-ray
there are five radiographic features
which one can look for they are air
Branca Graham's peribronchial cuffing
curly lines cephalization and the bat
swing pattern I'll talk about each one
at a time first up our air Bronco
Grahams
since bronchi are relatively thin walled
air filled structures surrounded by air
filled alveoli they are usually not
visible on x-ray however a pacification
of alveoli adjacent to a bronchus
results in the dark air field bronchi
becoming identifiable against a white
background in this example the patient
has a pacification of the right lower
lung zone probably the right middle lobe
as we will discuss in the next video if
we zoom in on the pacification we can
see an outline of a dark branching
structure which are the bronchi visible
bronchi are not only a manifestation of
air Branca grams but also of
peribronchial cuffing interstitial edema
can accumulate a round bronchi making
the bronchial walls thick this appears
like a ring when seen in cross-section
and like tram tracks when seen
longitudinally here is an x-ray with a
number of different findings if we zoom
in again on the right mid-long zone we
can see two ring shaped structures
adjacent to one another which are
bronchi seen in cross-section next are
curly a and B lines curly a lines are
diagonal on branching lines two to six
centimeters long extending from the
hilum they represent channels between
peripheral and central lymphatics curly
B lines are faint thin horizontal lines
1 to 2 centimeters long at the long
periphery usually at the bases they
represent inter lobular septa
in general curly be lines are much more
commonly seen and commonly referred to
than curly a lines in this example if we
zoom way in at the right lung base we
can see the tiny faint horizontal curly
B lines specifically indicating this
patient may have mild heart failure the
term cephalization refers to increase
the visibility of pulmonary vessels at
the lung apices as compared to the basis
it is suggestive of increased left
atrial pressure in this example if we
compare the average density of the
pulmonary vessels in the apices to the
middling zones we can see that they are
more prominent in the apices
unfortunately cephalization is highly
subjective and has relatively poor
interobserver agreement limiting its
utility as a radiographic distinguishing
feature of pulmonary edema lastly is the
so called bat swing pattern of a
pacification sometimes referred to
alternatively as a butterfly pattern or
angel's wings this refers to bilateral
parry higher concentration of a
pacification this is seen predominantly
in cardiogenic pulmonary edema but also
in some types of pneumonia particularly
viral pcp and aspiration it can be seen
in inhalational injury pulmonary alveoli
proptosis and in pulmonary hemorrhage so
how do these radiographic features help
distinguish cardiogenic from non
cardiogenic pulmonary edema in
cardiogenic edema the cardiac size is
typically enlarged while in non
cardiogenic edema
it is typically normal in cardiogenic
edema the regional distribution of
opacities is relatively homogeneous
while it is relatively patchy and non
cardiogenic edema air Branca Graham's
are common only in non cardiogenic edema
while peribronchial cuffing is common
only in cardiogenic edema
and concurrent pleural effusions and
curly be lines are more common in
cardiogenic although not listed
explicitly in this chart a batwing
pattern to the pasady s is most
consistent with cardiogenic edema though
it may be seen with some specific
ideologies of non cardiogenic edema as
listed on the previous slide finally
cephalization has historically been
associated with cardiogenic edema
however the subjectivity and lack of
interest regarding this finding limits
its usefulness if you recall back to
near the beginning of this video you may
remember that alveolar opacities can be
caused not just by edema in the alveoli
but also by pus or blood
therefore ideologies that diffuse
alveolar opacities without edema include
multi lowbar pneumonia and diffuse
alveolar hemorrhage I'll now move on to
discuss interstitial opacities there are
several subtypes of interstitial
opacities based upon radiographic
appearance the first are reticular
opacities which essentially means there
are too many lines this can create a
lace-like
or net-like appearance another subtype
is nodular opacities which means there
are too many dots or nodules for diffuse
interstitial disease the nodules are
almost always less than one centimeter
in size if the nodules are all less than
two millimeters it is sometimes referred
to as a miliary pattern due to the fact
that someone a long time ago thought the
nodules look like millet seeds
finally our reticular nodular opacities
which means there are too many lines and
too many dots so here's an example of a
reticular pattern that is too many lines
and here is a nodular one
and the last here are diffused
particular nodular capacities the
differential diagnosis of diffused
interstitial opacities is very large and
is generally difficult to place into
categories of groups other than those
diagnoses which cause a predominant
reticular pattern and those which cause
a predominant nodular pattern almost any
cause of interstitial opacities can lead
to a reticular nodular pattern those
diseases which cause a predominantly
reticular pattern of the fuchsia pass
''tis include idiopathic pulmonary
fibrosis connective tissue disease
atypical pneumonia such as that caused
by mycoplasma the idiopathic
interstitial pneumonias of which there
are several histologic subtypes which
cannot be distinguished on plain
radiographs asbestosis chronic
aspiration pulmonary drug toxicity
sarcoidosis chronic hypersensitivity
pneumonitis Langerhans cell
histiocytosis and lymphangitis
carcinomatosis as I said the
differential diagnosis is very long in
some cases there may be subtle clues
pointing towards one diagnosis over
others such as the presence of pleural
plaques suggesting a particular pattern
is due to a space no sis
however for the most part most of these
diseases are indistinguishable from one
another on plain radiographs when it
comes to the causes of diffused
interstitial opacities that cause a
predominantly nodular pattern these can
be broken down into those with nodules
under two centimetres and those with
nodules over two centimetres provided
one realizes that this cutoff is far
from absolute those diseases causing
small nodules include miliary
tuberculosis fungal infections silicosis
coal workers pneumoconiosis and
sarcoidosis
those which caused medium and large
nodules include metastatic cancer
subacute hypersensitivity pneumonitis
lymphoma sarcoidosis granulomatosis with
polyangiitis and rheumatoid nodules you
probably notice that sarcoidosis has
shown up on all three lists which is
because sarcoidosis has a wide variety
of manifestations in the lung
along with causing either reticular or
nodular interstitial patterns
sarcoidosis can also cause alveolar
opacities and is best known
radiographically as a cause of prominent
hilar lymph adenopathy I'll close this
video with a summary of a comparison
between alveolar and interstitial
opacities alveolar opacities showed low
bar or segmental distribution unless
they are diffuse or in the bats wing
pattern while interstitial opacities do
not respect low bar or segmental
boundaries the margin of alveolar
opacities is relatively hazy while
interstitial opacities have a relatively
sharp margin alveolar opacities may
contain air Branca Graham's if they are
caused by non cardiogenic pulmonary
edema while interstitial opacities are
generally devoid of them alveolar
opacities can change rapidly over time
with an ability to appear and disappear
within hours while interstitial
opacities generally evolve much more
slowly and finally alveolar opacities
are often described in highly subjective
terms such as fluffy cotton wool like or
cloud like interstitial opacities are
described in the semi objective terms a
particular nodular or reticular nodular
that concludes this video on diffused
lung processes the next video in this
series will cover focal lung processes
you
Voir Plus de Vidéos Connexes
Pulmonary 2 Lung Volumes and Ventilation
COVID-19 Autopsy Pathology Findings
Anatomy of a Chest X-Ray - How to Read a Chest X-Ray (Part 1)
VOCĂ SABERIA IDENTIFICAR BRONQUIOLITE VIRAL EM CRIANĂA?
Assessment of CXR Quality - How to Read a Chest X-Ray (Part 5) - MEDZCOOL
Pneumonia causes, symptoms, diagnosis, treatment, pathology
5.0 / 5 (0 votes)