Lung Flashcards
How to determine if Chest tube is intraparenchymal or in the pleural space?
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
Ddx for cystic lung disease
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
Which one affects the spleen: silicosis or sarcoidosis
Sarcoidosis
Name diseases associated with pulmonary ossification
Idiopathic
Amyloidosis: nodular form
Drug reaction
UIP: disseminated form
What thoracic mass should you look for in a patient with myasthenia gravis
Thymoma
DDx of mosaic attenuation pattern
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
DDx of centrilobular lung nodules
- Bronchiolitis
- Infection /w endobronchial spread (mycoplasm, aspergillosis)
- bronchoalveolar carcinoma /w airway spread
- subacute hypersensitivty pneumonitis
- bronchiolitides (obliterative bronchiolitis)
- RB-ILD
- pulmonary vasculitides (churg strauss)
Describe pathology and imaging features of lymphocytic interstitial pneumonitis
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
What is the most common pattern of lung involvement in sjogren?
NSIP
Can also be UIP and LIP pattern
describe the typical findings of NSIP
bilateral areas of GG and reticulation - diffuse or basal predominant
traction bronchiectasis with peribronchovascular/basal predominance
loss of volume
temporal homogeneity
honeycombing rare
What malignancy has the same/similar features as benign lymphoproliferative disorders on HRCT?
MALT lymphoma
This should be kept in mind in patients known for primary sjogren syndrome
What is the most common neoplasm in patients with primary Sjogren syndrome?
MALT lymphoma
HRCT findings of lymphocytic interstitial pneumonia?
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
CT findings of MALT lymphoma in lung?
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.
What are the mediastinal manifestations of primary sjogren syndrome?
Lymphadenopathy
Thymic lymphoid hyperplasia
Multilocular thymic cysts
What are multilocular thymic cysts associated with? (other pathology or possible etiology)
Autoimmune disorders such as primary sjogren
post thoracic surgery
post chemotherapy
possible related to chronic noninfectious inflammation
What is the Ddx for multilocular thymic cyst?
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
Lung manifestations of Primary Sjogren Syndrome?
Follicular bronchiolitis
Interstitial pneumonia (NSIP, UIP, organizing pneumonia, LIP)
MALT lymphoma
Amyloidosis
What is a ghon lesion and a ranke complex?
Ghon lesion: calcified parenchymal tuberculoma
Ranke complex: ghon lesion +
ipsilateral calcified hilar node
How to differentiate LCH from LAM on imaging
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
What is Birt-Hogg-Dube syndrome? What are its associations and CT chest findings?
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.
What is the primary risk factor for DEsquamative interstitial pneumonia? Also name other predisposing factors
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
CT findings of desquamative interstitial pneumonia?
Diffuse ground glass opacities in a symmetric bilateral distribution
Irregular linear opacities
Cysts
Bronchial wall thickening and emphysema (2nd to smoking)
Ddx of diffuse tracheal wall thickening (8)
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
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)
Interstitial lung disease pattern that is most commonly associated with scleroderma?
NSIP
UIP also associated but less common
What type of tuberculous lung infection is associated with necrotic mediastinal lymphadenopathy?
Primary infection
Secondary infection in immunocompromised patients (AIDS)
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
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
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
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
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.
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
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
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
What is the maximal normal thickness of the right paratracheal stripe?
4mm
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
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
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
Give 5 common posterior mediastinal masses
Foregut duplication cyst Descending aortic aneurysm Neurogenic tumor Extramedullary haematopoiesis Paraspinal abscess
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
what is the main risk factor for RB, RB-ILD and DIP?
Smoking
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
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
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
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
Ddx of bilateral upper lobe predominant fibrosis and bronchiectasis
Radiation fibrosis
TB
PMF
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
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