Lung Flashcards
(124 cards)
1
Q
How to determine if Chest tube is intraparenchymal or in the pleural space?
A
Look for pleural tag:
If CT in pleural space but surrounded by lung it will show a small area of lung invaginating around it and extending to pleural. Can see surround circular hyperdensity likely atelectatic lung
2
Q
Ddx for cystic lung disease
A
LAM Langerhan cell histiocytosis Lymphocytic interstitial pneumonitis Honeycombing in UIP PCP Sarcoidosis Desquamative interstitial pneumonia Amyloidosis Birt-Hogg-Dube syndrome Light chain deposition disease Follicular bronchiolitis Cystic pulmonary metastases
3
Q
Which one affects the spleen: silicosis or sarcoidosis
A
Sarcoidosis
4
Q
Name diseases associated with pulmonary ossification
A
Idiopathic
Amyloidosis: nodular form
Drug reaction
UIP: disseminated form
5
Q
What thoracic mass should you look for in a patient with myasthenia gravis
A
Thymoma
6
Q
DDx of mosaic attenuation pattern
A
Obstructive small airway disease:
decreased perfusion to poorly ventilated regions (e.g. bronchiectasis, cystic fibrosis, constrictive bronchiolitis)
Occlusive vascular disease:
relative oligaemia of low attenuation regions (e.g. chronic PE)
Parenchymal disease:
ground glass opacity in high attenuation regions
7
Q
DDx of centrilobular lung nodules
A
- Bronchiolitis
- Infection /w endobronchial spread (mycoplasm, aspergillosis)
- bronchoalveolar carcinoma /w airway spread
- subacute hypersensitivty pneumonitis
- bronchiolitides (obliterative bronchiolitis)
- RB-ILD
- pulmonary vasculitides (churg strauss)
8
Q
Describe pathology and imaging features of lymphocytic interstitial pneumonitis
A
diffuse infiltration of the interstitium and alveolar spaces by lymphocytes and plasma cells.
Diffuse mid to lower lung zone changes including GG opacities, nodules, cysts and bronchovascular/lymph channel thickening
9
Q
What is the most common pattern of lung involvement in sjogren?
A
NSIP
Can also be UIP and LIP pattern
10
Q
describe the typical findings of NSIP
A
bilateral areas of GG and reticulation - diffuse or basal predominant
traction bronchiectasis with peribronchovascular/basal predominance
loss of volume
temporal homogeneity
honeycombing rare
11
Q
What malignancy has the same/similar features as benign lymphoproliferative disorders on HRCT?
A
MALT lymphoma
This should be kept in mind in patients known for primary sjogren syndrome
12
Q
What is the most common neoplasm in patients with primary Sjogren syndrome?
A
MALT lymphoma
13
Q
HRCT findings of lymphocytic interstitial pneumonia?
A
Diffuse, mid to lower lobe predominance
bilateral ground glass attenuation
air cysts
interlobular septal thickening
thickening of the peribronchovascular interstitium
poorly defined centrilobular or subpleural nodules
14
Q
CT findings of MALT lymphoma in lung?
A
solitary or multiple nodules/masses with areas of air-space consolidation or ground glass attenuation
typically located along a bronchovascular bundle.
may have traction bronchiectasis.
may have interlobular septal thickening within or around the lesion.
15
Q
What are the mediastinal manifestations of primary sjogren syndrome?
A
Lymphadenopathy
Thymic lymphoid hyperplasia
Multilocular thymic cysts
16
Q
What are multilocular thymic cysts associated with? (other pathology or possible etiology)
A
Autoimmune disorders such as primary sjogren
post thoracic surgery
post chemotherapy
possible related to chronic noninfectious inflammation
17
Q
What is the Ddx for multilocular thymic cyst?
A
Thymoma with severe cystic change
mature cystic teratoma
Hodgkin disease
if there is a solid component or irregular thickening of the cyst wall, it may indicate malignancy such as thymic carcinoma or MALT lymphoma
18
Q
Lung manifestations of Primary Sjogren Syndrome?
A
Follicular bronchiolitis
Interstitial pneumonia (NSIP, UIP, organizing pneumonia, LIP)
MALT lymphoma
Amyloidosis
19
Q
What is a ghon lesion and a ranke complex?
A
Ghon lesion: calcified parenchymal tuberculoma
Ranke complex: ghon lesion +
ipsilateral calcified hilar node
20
Q
How to differentiate LCH from LAM on imaging
A
Cysts may be round but are often irregular, bilobed, cloverleaf-shaped, or bizarre shapes. Irregular cysts, cysts with nodules, and upper zone predominance with sparing of the cos- tophrenic angles are features that distinguish LCH from lymphangioleiomyomatosis
21
Q
What is Birt-Hogg-Dube syndrome? What are its associations and CT chest findings?
A
rare autosomal-dominant disorder characterized by fibrofolliculomas distributed over the face, neck, and upper trunk; renal tumors ranging from benign oncocytomas to renal cell carcinomas; colonic polyposis; and chorioretinal disease
Thoracic findings include bullous emphysema, thin-walled cysts (80%), and pneumothorax.
22
Q
What is the primary risk factor for DEsquamative interstitial pneumonia? Also name other predisposing factors
A
90% are smokers
Other associations:
autoimmune / systemic disorders, e.g. rheumatoid arthritis, scleroderma
infection, e.g. HIV
toxin, occupational or environmental exposure, e.g. asbestos
drugs
23
Q
CT findings of desquamative interstitial pneumonia?
A
Diffuse ground glass opacities in a symmetric bilateral distribution
Irregular linear opacities
Cysts
Bronchial wall thickening and emphysema (2nd to smoking)
24
Q
Ddx of diffuse tracheal wall thickening (8)
A
Wegener’s granulomatosis
sarcoidosis
amyloidosis
post-intubation stenosis
infection (i.e. rhinoscleroma, tuberculosis).
Inflammatory bowel disease
relapsing polychondritis: characteristic sparing of the posterior tracheal membrane
tracheobronchopathia osteochondroplastica
25
What are imaging findings of tracheobronchopathia osteochondroplastica
Focal or diffuse tracheal or bronchial nodules, may be calcified. They protrude into tracheal lumen.
Thickened tracheal cartilage with posterior sparing (membranous portion)
26
Interstitial lung disease pattern that is most commonly associated with scleroderma?
NSIP
UIP also associated but less common
27
What type of tuberculous lung infection is associated with necrotic mediastinal lymphadenopathy?
Primary infection
| Secondary infection in immunocompromised patients (AIDS)
28
What is underlying pathology of organizing pneumonia?
presence of intraluminal granulation tissue within alveolar ducts and surrounding alveoli associated with chronic inflammation of the surrounding lung parenchyma. Granulation tissue polyps may also be present in the respiratory bronchioles.
```
It is a common reaction pattern seen in association with:
pulmonary infection
connective tissue disease
inflammatory bowel disease
inhalational injury
hypersensitivity pneumonitis
drug toxicity
malignancy
radiation therapy
aspiration
```
when idiopathic, termed COP
29
Typical clinical features of COP?
```
2-4 month history of nonproductive cough
low grade fever, malaise, SOB
PFTs show restrictive pattern
mean age 50-60
respond to steroids
```
30
What are the typical radiologic findings of COP?
Typical appearance:
Patchy, nonsegmental, unilateral or bilateral areas of airspace consolidation.
Subpleural/peribronchial/ perilobular distribution
multifocal areas of consolidation change in location over a matter of weeks
reversed halo sign/atoll sign (not specific for COP)
Also:
small ill-defined peribronchial/peribronchiolar nodule 30-50% of cases
bronchial wall thickening/bronchiectasis
irregular reticular opacities can be present but not major feature
ground glass opacity
31
What is the differential diagnosis for migration and spontaneous regression of areas of consolidation on chest CT?
```
COP
secondary OP
eosinophilic pneumonia
pulmonary hemorrhage
pulmonary vasculitis
```
32
What are the features of the bronchial wall thickening and dilatation that is present in organizing pneumonia?
Usually restricted to areas of consolidation
bronchial dilatation is usually reversible, resolving completely along with the parenchymal abnormalities after treatment with corticosteroids.
33
What are the histologic findings of acute interstitial pneumonia?
Diffuse alveolar damage
Histologic features are identical with those of ARDS
in the chronic phase, typically 2 weeks or more after injury, there is progressive fibrosis with collagen deposition
34
What are typical HRCT findings of AIP?
in the early stages:
bilateral ground glass opacities, patchy or diffuse
consolidation
geographic appearance due to focal sparing
crazy-paving pattern
as fibrosis develops:
traction bronchiectasis
minority of patients have honeycombing
35
What is a perilobular pattern?
Chest CT finding
poorly defined linear opacities that are of greater thickness than those encountered in thickened interlobular septa and that have an arcade-like or polygonal appearance.
present in 60% of cases of COP
36
What is the maximal normal thickness of the right paratracheal stripe?
4mm
37
The azygoesophageal recess corresponds to the interface of which structures?
Right lower lobe
Right wall of the esophagus
Azygos vein
Any convexity in this region if abnormal in adults
38
What is the best view to assess for subcarinal lymphadenopathy on CXR?
Lateral view
It creates an abnormal opacity obscuring the normally clear infrahilar window
39
A mediastinal mass extending above the level of the clavicle is located in which part of the mediastinum?
Middle or posterior
The anterior mediastinum does not extend beyond the level of the clavicles
40
Give 5 common posterior mediastinal masses
```
Foregut duplication cyst
Descending aortic aneurysm
Neurogenic tumor
Extramedullary haematopoiesis
Paraspinal abscess
```
41
What imaging findings can help you differentiate an embolized guidewire from a VP shunt on chest radiograph?
Guidewires overlie vascular structures whereas VP shunts usually have a more lateral path
Guidewires appear as a single linear metallic density whereas a VP shunt's lumen produces a tubular density
A lateral view can confirm the subcutaneous location of a VP shunt
42
what is the main risk factor for RB, RB-ILD and DIP?
Smoking
43
True or false
The majority of patients with respiratory bronchiolitis have poorly defined centrilobular nodules on HRCT
False
In the majority of patients who have RB, the histologic abnormalities are too mild to be detected on HRCT.
When present, HRCT findings consist of poorly defined centrilobular nodules and multifocal ground-glass opacities
44
What are the 3 most common HRCT findings in RB-ILD?
centrilobular nodules
ground glass opacities
thickening of bronchial walls
upper lobe emphysema common due to smoking
45
What malignancies cause calcifying pulmonary metastases?
Sarcoma (osteosarcoma, chondrosarcoma, synovial sarcoma)
mucinous type carcinomas (colon, ovarian, breast)
thyroid cancer (medullary thyroid carcinoma)
treated metastatic choriocarcinoma
giant cell tumor of bone
Tumors that cause OSSIFYING pulmonary metastases:
```
osteosarcoma
chondrosarcoma
giant cell tumor of bone
parotid ADK
gastric ADK
```
so there is overlap between both
46
What is metastatic pulmonary calcification? What is CT appearance and Ddx?
Calcium deposition in normal lung pulmonary parenchyma due to multiple etiologies, malignant and benign:
```
chronic renal failure (most common)
primary/secondary hyperparathyroidism
sarcoidosis
Vit D intoxication
IV calcium therapy
multiple myeloma
massive osteolysis caused by bone metastases
```
typically, centrilobular fluffy ground-glass nodular opacities that may or may not appear calcified
47
Ddx of bilateral upper lobe predominant fibrosis and bronchiectasis
Radiation fibrosis
TB
PMF
48
What patterns of calcification are considered benign in a solitary lung nodule?
What are the exceptions to this rule?
Diffuse
central
laminated
popcorn
exceptions:
When a patient is known to have a primary tumor such as osteosarcoma, chondrosarcoma or a GI tumor.
Previous chemotherapy
49
True or false: Lung lesions with both solid and ground glass components have a higher chance of being malignant than a purely solid or ground glass lesion
TRUE
50
Fleischner guidelines for lung nodule followup are applicable to which category of patients?
Subjects 35 years or older without a known or suspected malignancy.
51
What is CPFE syndrome
Combined pulmonary fibrosis and emphysema
Combined pattern of upper lobe predominant emphysema and lower lobe predominant pulmonary fibrosis, usually UIP pattern however other patterns have also been reported.
Typically in male smokers, high morbidity and mortality
52
What is the predominant HRCT finding in desquamative interstitial pneumonia?
Areas of ground glass opacity, often with a subpleural and basal predominance
53
LIP usually occurs in association with what other conditions? (4 most common)
Sjogren
Autoimmune disorders
Dysproteinemia
AIDS
Can also occur in association with:
Bone marrow transplantation
Common variable immunodeficiency
Drug reaction
Idiopathic LIP is rare
54
What 2 HRCT features are helpful in distinguishing LIP from lymphoma?
Presence of cysts
Lack of pleural effusions
Airspace consolidation and large nodules are also more common in malignant lymphoma
55
Ddx of perilymphatic nodules (6)
```
Sarcoidosis
Lymphangitic spread of carcinoma
Silicosis
Coal worker's pneumoconiosis
Lymphoid interstitial pneumonia
Amyloidosis
```
56
What does a tree-in-bud pattern represent (path)
| What is the ddx? (3)
Dilated and impacted mucus or pus-filled centrilobular bronchioles
Ddx:
Endobronchial spread of infection (TB, MAI, any bacterial bronchopneumonia)
Airway disease associated with infection (CF, bronchiectasis)
Airway disease associated primarily with mucus retention (ABPA, asthma)
57
What are the 4 types of bronchiectasis?
Traction
- caused by surrounding fibrosis
Varicose
- beaded appearance, dilated bronchi with areas of narrowing
Cystic
- cyst like bronchi that extend to the pleural surface
- air fluid levels common
Cylindrical
- uniform caliber, do not taper, parallel walls
- most common
58
Describe the anatomy of the secondary lobule
Smallest lung unit surrounded by connective tissue septa
Measures 1-2cm and contains 5-15 pulmonary acini (contain the alveoli).
Terminal bronchiole in the center, paralleled by centrilobular artery.
Pulmonary veins and lymphatics within interlobular septa
Two lymphatic systems: central network, along bronchovascular bundle towards center of lobule and peripheral network within interlobular septa and along the pleural linings.
59
Ddx of random distribution of nodules in the lungs (5)
Hematogenous metastases
Miliary tuberculosis
Miliary fungal infections
Sarcoidosis may mimick this pattern, when very extensive
Langerhans cell histiocytosis (early nodular stage)
60
Ddx of acute ground glass opacity (4)
Pulmonary edema (CHF, ARDS)
Pulmonary hemorrhage
Infection (viral, PCP, mycoplasma)
Acute eosinophilic pneumonia
61
Ddx of chronic ground glass opacity (6)
```
hypersensitivity pneumonitis
Organizing pneumonia
Chronic eosinophilic pneumonia
Alveolar proteinosis
Lung Fibrosis (UIP, NSIP)
Bronchoalveolar carcinoma
```
62
What are the 3 etiological categories in mosaic attenuation of the lung?
Infiltrative process adjacent to normal lung
Normal lung appearing relatively dense adjacent to lung with air trapping
Hyperperfused lung adjacent to oligemic lung due to chronic thromboembolic disease
63
Ddx of crazy paving pattern
```
NSIP
Organizing pneumonia (COP/BOOP)
Infection (PCP, viral, Mycoplasma, bacterial)
Neoplasm (Bronchoalveolarca (BAC)
Pulmonary hemorrhage
Edema (heart failure, ARDS, AIP)
Alveolar proteinosis
Sarcoid
```
64
Ddx of UIP (etiology)
```
IPF
RA
Scleroderma
Drug reaction
Asbestosis
End stage hypersensitivity pneumonitis
```
65
What are the key findings of hypersensitivity pneumonitis?
Centrilobular nodules of ground-glass opacity or mosaic pattern in farmer or bird fancier
66
What is the typical location of a post-intubation (ETT and tracheostomy) tracheal stenosis?
Endotracheal tube: subglottic region at the cuff site
| Tracheostomy: postextubation stenosis at stoma site
67
DDx of focal stenosis of the central airways
Postintubation
Postinfectious - typically multifocal (TB, granulomatous infection, fungal infection)
Posttransplantation - at site of anastomosis
Sarcoidosis
Behcet syndrome
Crohn's disease - rare
Wegener - may be focal or diffuse
68
What is the etiology of tracheolaryngeal papillomatosis?
Human papilloma virus infection
69
What is rhinoscleroma?
Rhinoscleroma is a chronic, progressive, granulomatous
infection that affects the respiratory tract
from the nose to the bronchi. The etiologic agent
is a gram-negative diplobacillus, Klebsiella rhinoscleromatis.
The radiographic findings include thickening
of the tracheal wall, nodular deformity
of the tracheal mucosa, subglottic stricture, and
concentric narrowing of the trachea and central
bronchi. These regions of narrowing may be
focal or diffuse and are of soft-tissue density without
calcification.
70
What is PPFE? What are the pathologic findings?
Pleuroparenchymal fibroelastosis
rare condition characterized by elastotic fibrosis of the pleural and adjacent parenchyma. There is marked thickening of the visceral pleural due to a homogeneous mixture of elastic tissue and dense collagen associated with intra-alveolar fibrosis and septal elastosis of the adjacent parenchyma.
71
What are the plain radiograph and HRCT findings of PPFE?
CXR: marked pleural thickening mainly in the upper lung zones associated with cephalad hilar retraction
HRCT: upper lung zone predominant pleural thickening and subpleural reticulation association with upper lobe volume loss and cephalad retraction of the hila.
72
Ddx for cavitating lung lesion (there's a mnemonic)
CAVITY
Cancer
- primary or Mets (SCC most common)
Autoimmune
- wegener's, RA
Vascular
- bland and septic pulmonary emboli
Infection
- abscess (bacterial, fungal)
- tuberculosis
Trauma
- pneumatocele
Youth
- CPAM
- Sequestration
- bronchogenic cyst
73
True or false:
CPAM can have a connection to the tracheobronchial tree
True
74
What is CPAM?
Congenital pulmonary airway malformation
Multicystic mass of segmental lung tissue with abnormal bronchial proliferation.
They are part of the spectrum of bronchopulmonary foregut malformations.
75
What is the most common CPAM subtype?
Type 1 (70%)
Large cysts with 1 or more dominant cysts (2-10cm)
76
What CPAM subtype typically affects an entire lobe and is composed of microcysts?
Type 3
Cysts
77
Type 2 CPAM is associated with what other abnormalities?
Renal agenesis or dysgenesis
Pulmonary sequestration
Congenital cardiac anomalies
78
Why are silicosis nodules upper lung zone predominant? Why do these patients have lymphadenopathy?
Because the lymphatic system is poor in the apices, therefore silica particles are not cleared by macrophages.
Lymphadenopathy is secondary to the silica particles that are cleared by the macrophages in the lung bases.
79
When a patient takes a deep breath, which part of the lung is most ventilated?
Bottom
| The apices are already maximally distended prior to taking a deep breath.
80
Most important differentiating factor between NSIP and UIP on CT?
Sparing of the periphery in NSIP
81
TRUE OR FALSE
Alpha-1 antitrypsin deficiency is predominantly an upper lobe process
FALSE
Alpha-1 antitrypsin deficiency is a bloodborn process and involves primarily the base of the lungs.
82
What lung spirometry finding indicates the presence of COPD?
FEV1/FVC < 70%
fev1: forced expiration in 1 second
fvc: forced vital capacity
83
What are the values for mild to very severe COPD?
FEV1 determines severity
<80%: mild
50-80%: moderate
30-50%: severe
<30%: very severe
84
A partial airway (intrabronchial) and partial lung growth pattern is characteristic of what lung tumor?
Carcinoid tumor
85
TRUE OR FALSE
Calcifications in a lung lesion signifies it is benign
FALSE
Calcifications in a lung lesion do not always signify it is benign. Example: Carcinoid
86
What are the 2 most common primary tracheal malignancies?
1- SCC
| 2- adenoid cystic carcinoma
87
When assessing a nodular airway, the presence of nodularity involving the outer surface is more indicative of what type of process (neoplastic, infectious or inflammatory)?
Neoplastic
88
What is the most common location of adenoid cystic carcinoma of the lung?
Trachea and main bronchi
10% are located in the lung periphery
89
What is the most common location of mucoepidermoid carcinoma of the lung?
Main or lobar bronchi
A few are present in the trachea
90
What are the most common origins of endotracheal metastasis (5)
Kiss My R B C
```
Kaposi sarcoma
Melanoma
Renal
Breast
Colon
```
Melanoma has the highest rate of endotracheal metastasis, but genitourinary are the most likely origin of an endotracheal metastasis
91
What is the age distribution of pulmonary blastoma?
First and seventh decades of life
| Primarily males
92
What are the indeterminate/malignant patterns of calcification in a solitary pulmonary nodule? (2)
Stippled
| Eccentric
93
What are the benign patterns of calcification in a solitary pulmonary nodule? (4)
Laminar, concentric
Diffuse
Central
Popcorn
94
Why does tracheobronchial papillomatosis require imaging followup?
They are at increased risk of transformation into squamous cell carcinoma
95
TRUE OR FALSE
The visceral pleura has no pain receptors
TRUE
The parietal pleural has pain receptors
96
Which pleural space communicates with the lymphatics?
Parietal pleura
97
What impact does an incomplete minor fissure have for surgical planning in cases requiring lobectomy?
In cases requiring upper lobectomy, the presence of an incomplete minor fissure means there will be direct communication between the upper lobe and middle lobe, requiring more extensive resection.
98
What does extrapleural fat hypertrophy in the setting of empyema imply?
That it is a chronic process
99
What areas are typically involved in asbestos related pleural disease?
Hemidiaphragm pleural, lateral chest wall, paravertebral
80% are bilateral
Does not involve the mediastinal pleura and apices
100
Asbestos related pleural disease involves the visceral or parietal pleura?
parietal pleural surface
101
What features are suggestive of malignant pleural disease?
>1cm
nodular
circumferential pattern of pleural thickening
involves mediastinal pleura
A pleural effusion is the most sensitive finding, but not specific
102
TRUE OR FALSE
Imaging does not reliably differentiate malignant pleural mesothelioma from pleural metastasis
True
103
TRUE OR FALSE
Fibrous tumour of the pleura is associated to asbestos exposure
FALSE
Not associated to asbestos exposure
104
Imaging features of solitary fibrous tumour of the pleura?
Well defined, smooth, lobular
abuts pleural surface
elongated, lenticular
Can be pedunculated with positional mobility
Can be heterogeneous in large masses (hemorrhage, necrosis, cysts)
enhances on C+
105
How many layers of intercostal muscles are there?
innermost intercostal muscle
internal intercostal muscle
external intercostal muscle
106
Ddx of silhouetting of the right heart border on PA chest radiograph?
Pectus excavatum
| consolidation
107
What is a Haller index?
An index used to assess the severity of pectus excavatum.
The Haller index (maximal transverse diameter/narrowest AP length of chest) is used to assess severity of incursion of the sternum into the mediastinum. Normal Haller index is 2.5. Significant pectus excavatum has an index greater than 3.25, representing the standard for determining candidacy for repair .
108
What is the name of an empyema that extends into the chest wall?
Empyema necessitans
109
Osteomyelitis/septic arthritis involving the sternoclavicular joint is particularly prevalent in which patient population?
IV drug users
| HIV positive patients
110
What are the most common primary tumors to metastasize to the chest wall?
```
Lung
Breast
Prostate
Renal
Melanoma (highest incidence)
```
111
What is the pattern of spread of breast cancer when it metastasises to the chest wall?
Supraclavicular fossa
Internal mammary chain (lymph nodes)
sternum
112
Diagnosis:
Bilateral infrascapular soft tissue masses with internal strands of fat, located deep to serratus anterior or latissimus dorsi
elastofibroma dorsi
113
Describe intralobar vs extralobar pulmonary sequestration
Pulmonary sequestrations are non-functioning masses of lung parenchyma, without connections to the tracheobronchial tree, which derive their arterial supply from systemic vessels.
INTRALOBAR
The parenchymal tissue lies in close relation to the normal lung, sharing its pleural covering. Arterial supply usually from aorta. Venous drainage is to the pulmonary system and left atrium, creating left-to-left shunt. Always located above diaphragm.
EXTRALOBAR
The parenchymal tissue is entirely separate from the normal lung and is invested in its own pleural layers. Arterial supply usually from aorta (can be other systemic arteries). Venous drainage is usually systemic, to IVC or via azygous system. Can be located below the diaphragm.
114
Which type of pulmonary sequestration is most likely to present with other congenital malformations? (give percentage and name 3 most likely associated malformations)
Extralobar pulmonary sequestration (60% of cases). Only 6-12% of intralobar sequestrations have associated congenital anomalies.
Congenital malformations found with extralobar sequestration:
- Diaphragmatic hernia
- Congenital heart disease
- CPAM
115
What is constrictive bronchiolitis (bronchiolitis obliterans)?
Constrictive bronchiolitis is defined histologically as concentric luminal narrowing of the membranous and respiratory bronchioles secondary to submucosal and peribronchiolar inflammation and fibrosis without any intraluminal granulation tissue or polyps.
116
What are the potential etiologies of constrictive bronchiolitis (bronchiolitis obliterans)?
```
Idiopathic
Postinfectious (viral, mycoplasma)
Noxious fume inhalation
Graft-versus-host disease
Rheumatoid arthritis
IBD
Penicillamine therapy
```
117
What are the CT findings of constrictive bronchiolitis (bronchiolitis obliterans)?
Direct CT signs of bronchiolitis usually absent
Mosaic attenuation
Air trapping
Bronchiectasis
Reduction in the size of the pulmonary vessels (in areas of low attenuation)
118
What are the direct CT signs of small airways disease (bronchiolitis)?
Tree-in-bud opacities
centrilobular nodules (typically GG)
bronchiolectasis
119
What are the indirect CT signs of small airways disease (bronchiolitis)?
Air trapping (mosaic attenuation)
120
TRUE OR FALSE
Air trapping is common in healthy individuals
TRUE
Mastora et al.:
Isolated lobules of air trapping in 53% of healthy nonsmokers
Segemental/lobar air trapping in 8% of healthy nonsmokers
121
Name this disease:
Impairment of swallowing due to compression from an aberrant right subclavian artery
Dysphagia lusoria
122
What is pulmonary leukostasis?
Pulmonary leukostasis is a medical emergency that is most commonly seen as a complication of chronic myeloid leukaemia in blast crisis, and acute myeloid leukemia when white blood cell counts are over 100 x 109/L (100,000/microL). Symptoms are due to small pulmonary vessels or coronary artery obstruction by leukaemic cells.
Chest xray ranges from normal to airspace pulmonary edema, usually no evidence of interstitial infiltrates.
123
What is Retinoic Acid Syndrome?
Pulmonary complication post ATRA treatment for AML. Characteristically takes place 10 days after initiation of treatment. Patients develop dyspnea, fever, weight gain, pulmonary opacities and pleural effusions.
124
What are the imaging findings of Retinoic Acid Syndrome?
Chest radiographs and CT images obtained in patients with retinoic acid syndrome show nonspecific findings of pulmonary edema and/or hemorrhage.
Other possible findings, including poorly defined nodules and areas of consolidation, may be due to hemorrhage from damaged endothelial cells.
