Air space disease Flashcards
The lingular section of the left lung is homologue to what ?
the right middle lobe
what is the azygous fissure/ lobe?
it is created by downward migration of the azygous vein. as it migrates, it takes a portion of the parietal/ visceral pleura of the upper right lobe. this separates a fraction of the lung into a new lobe
What is another name for the anterior mediastinum?
cardiac
What is another name for the middle mediastinum?
the vascular & lymphadenopathy of the hilar area
What is another name for the posterior mediastinum?
neurogenic
neurofibromas
What are the 2 patterns of disease seen in the lung & what are examples of each?
- interstitial space disease: AS or RA
2. air space disease: MC pneumonia
Where is the primary lobule located and what is its purpose?
Aka: acinus
located distal to the respiratory bronchiole
it is the functional unit of respiration
Where is the secondary lobule located and what is it comprised of ?
located distal to the terminal bronchile
comprised of 4-5 primary lobules, 1-2 cm
How do alveoli communicate?
with each other via Pores of Kohn
with distal bronchioles via Canals of Lambert
What is interstitium and what are the 3 spaces of it?
it is the connective tissue support network within the lung
- axial
- parenchymal
- peripheral
Where is the axial space of the interstitium?
surrounds the primary bronchi and pulmonary artery
Where is the parenchymal space of the interstitium?
surrounds the alveoli
Where is the peripheral space of the interstitum?
between visceral pleura and lung parenchyma
What is the pattern of interstitial lung disease seen on film?
“toothpick” pattern
What is the pattern of alveolar/ airspace lung disease seen on film?
“cloud-like” pattern
What causes the “cloud-like” pattern of alveolar lung disease?
normal radiolucent lung tissue becomes white/ radiopaque if air within acini is replaced by BEPT; this leads to consolidation which leads to loss of air in alveolar space without loss in lung volume
What type of epithelial cells most commonly line the alveoli?
90% are type I squamous pneumocytes that lack the ability of mitosis
What is pnemocystic carinii?
a mix of airspace and interstitial
MC infx in HIV+
caused by P. jiroveci fungus
What is the “Silhouette” sign?
it is a loss of radiodense border secondary to a radiodense pathology positioned continuous with normal structure
How is the “Silhouette” sign helpful in dx chest pathology?
allows the observer to determine the location or presence of abnormality in relation to normal structure
What does a negative Silhouette sign with a dx of pneumonia indicate?
that the cardiac tissues are not touching the pathology. the pathology is either in front or in back of the heart
What does a positive Silhouette sign with a dx of pneumonia indicate?
the heart shadow is not seen, this indicates that the pathology is touching the heart
If the right heart border is obliterated on film, where is the pathology?
Right middle lobe
If the left heart border is obliterated on film, where is the pathology
Lingular section of upper lobe
If the right hemidiphragm is obliterated on film, where is the pathology
lower RIGHT lobe
If the left hemidiphragm is obliterated on film, where is the pathology
lower LEFT lobe
If the ascending aorta is obscured, where is the pathology?
Right UPPER lobe
If the aortic arch is obscured, where is the pathology?
LEFT upper lobe
What is the “air bronchogram” sign?
air filled bronchi normally not seen because they are surrounded by air filled lung
they appear as radiolucent tubular densities if the lung is filled with water
What is atelectasis?
incomplete air filling and under expansion of the lung. suggests presence of another disease
What are the radiographic findings of atelectasis?
- direct findings = displaced fissures, increased radiodensity
- indirect findings = elevated diaphragm
What are the 5 types of atelectasis?
- obstructive/ resorption
- compressive (extrapulmonary)
- passive (intrapulmonary)
- contraction/ cicatrization
- newborn
What is the cause of obstructive atelectasis?
airway obstruction
this is the MC type
What is the cause of compressive atelectasis
pulmonary mass/ SOL inside the lung
What is the cause of passive atelectasis
pleural mass (pneumothorax)/ SOL external to the lung
What is the cause of contraction/ cicatrization atelectasis
scarring & contracture of pulmonary tissue after infection, scleroderma, radiation, etc
What is an acceptable diaphragm displacement difference measurement side to side?
2 cm
What are the radiographic findings of atelectasis?
superior migration of right minor fissure and increased radiodensity of collapsed right upper lobe
What is the Reverse “S” configuration / “S” sign of Golden?
collapse of right upper lobe leads to superior migration of horizontal fissure which then bulges inferiorly near hilar mass
What are the radiographic findings of Atelecstasis of the right upper lobe?
high RT hemidiphragm, elevated horizontal fissure, reverse “S” configuration
What is Bronchial Asthma?
widespread, REVERSIBLE, episodic narrowing of airways
What are the 2 types of Bronchial Asthma and their causes?
- Extrinsic: due to environmental exposure
2. Intrinsic: due to immunological response (exercise or infx)
What are the radiographic findings of acute Bronchial Asthma?
hyperinflation of the lung, increased radiolucency, possible diaphragm depression, barrel chest appearance
What are the radiographic findings of chronic Bronchial Asthma?
normal or prominent interstitium, possible thick bronchi
What are the S/S of Asthma?
wheezing, prolonged expiration, dyspnea & cough
What is Bronchiectasis & what are the types?
chronic, IRREVERSIBLE dilation of bronchi
types based on appearance: cylindrical, varicose & saccular
What are the radiographic findings of Bronchiectasis?
thick bronchial walls, altered lung volume, honey comb appearance
What is a congenital bronchiogenic cyst?
anomalous out pouching of the primitive foregut, complete separation from the airway
80% are medialstinal
What is a bronchopulmunary sequestration?
congenital malformation of the foregut resulting in separation of a portion of the lung from the bronchial tree
appears as a radiodense mass above or below diaphragm
Where are extralobular sequestrations located?
intralobular?
extralobular: 90% are on the LEFT
intralobular: 60% are on the RIGHT
What is emphysema?
chronic dilation of the air space distal to the terminal bronchi (secondary lobule)
characterized by acinar wall destruction, large aggregate air spaces
How are types of emphysema based and what are they?
Based on region:
centriolobular, panacinar, distal acinar, irregular
What are the radiographic features of emphysema?
bilaterally flat & slanted, depressed hemidiphragm thin heart shadow lung over inflation / increased radiolucency increased retrosternal space barrel chest increased widened intercostal spaces prominent hilar vasculature bullae
What is the most reliable radiographic feature of emphysema
increased retrosternal space
What is bullous emphysema?
damage & loss of elasticity of the bronchioles & alveolar sacs, chronic dilation that traps stale air in airspace. rupture of small capillaries causes less efficient circulation & gas exchange
What is a characteristic radiographic feature of emphysema?
the heart twists and looks more narrow due to diaphragm no supporting it below
only moderate to severe forms are detectable on film
