19 Introduction to Chest Radiology 2 Flashcards
1
Q
Pattern approach
- Puzzle
- Location
- Pattern
A
- Puzzle
- History
- Physical exam,
- Labs
- PFT
- CXR / CT
- Location
- Lung
- Pleura
- Mediastinum
- Chest wall
- Pattern
- Degree of inspiration
- Lungs too black / white

2
Q
Radoilogic patterns
- Lungs are too white
- Lungs are too black
- Other
A
- Lungs are too white
- Consolidation
- Ground glass attenuation
- Atelectasis
- Reticular / nodular (interstitial disease)
- Airspace (acinar)
- Mixed
- Lungs are too black
- Air trapping – emphysema
- Bronchiectasis
- Other
- Pulmonary nodule or mass
- Cyst (multiple): cystic and cavitary disease
- Pleural effusion
- Lymphadenopathy
- Mediastinal widening
3
Q
Air space
A
- Gas-containing portion of lung parenchyma, to include acini
- Exclude the interstitium and purely conductive portion of lung
- Consolidation: etiology
- Pneumonia
- Pulmonary edema
- Aspiration
- Near drowning
- Malignancy

4
Q
Air space consolidation
A
- Air in alveoli is replaced by water, blood, pus, or tumor; results in confluent opacity which obscures broncho-vascular margins
- May be focal, patchy, or diffuse
- Air-bronchogram: radiologic appearance of an air-containing bronchus, surrounded by consolidated lung
5
Q
Air space consolidation: differential
- Edema
- Infectious
- Inhalation
- Neoplasm
- Metabolic
- Other
A
- Edema
- Fluid overload (heart, renal failure)
- Infectious
- Pneumonia
- Inhalation
- Aspiration, toxic gases, drowning
- Neoplasm
- Adeno CA, lymphoma, mets
- Metabolic
- Alveolar proteinosis
- Other
- Pulmonary hemorrhage
- Adult respiratory distress syndrome (ARDS)
6
Q
Consolidation: radiologic signs
A
- Silhouette sign (loss of)
- Loss of normal lung – soft tissue interface
- Enables anatomic localization
- Air-bronchogram sign
- Air filled bronchi are surrounded by consolidated lung
- Bulging fissure sign
- Lobar consolidation with copious pus causes bulging of the fissure
7
Q
“Loss of the silhouette” sign
A
- Localize lung pathology
- When air in lung is When air in lung is tissue (pneumonia), the normal interface between lung and heart is lost

8
Q
Consolidation: strep pneumonia RUL
A
- Silhouette sign
- RUL consolidation obscures normal air – soft tissue interface between lung & heart
- Bulging fissure sign
- Minor fissure bows downward
- Air-bronchogram sign
- Air-filled bronchus is patent
- Surrounding lung is consolidated

9
Q
Pneumonia LUL
A
- In lingula
- Lobar
- Lobar on CT
- Dense LUL consolidation
- Mild posterior bulging of L major fissure
- Most LUL airways are filled with pus
- Several air-bronchograms

10
Q
“Round” pneumonia: legionella
A
- More common finding in kids
- May mimic malignancy

11
Q
Consolidation
- Edema
- Aspiration
- Drowning
- Lung cancer
A
- Edema
- Aspiration
- Contents in stomach or oro-pharynx are inhaled into trachea and lungs
- Results in consolidation of dependent portions of lung
- Drowning
- Aspiration of water
- Consolidation is not always pna
- Lung cancer
- Pneumonic form mimics pneumonia

12
Q
Ground glass opacity
A
- Hazy increased lung attenuation
- Preserved broncho-vascular markings / margins
- Partial filling of alveoli, interstitial thickening, increased capillary blood flow
- Individual deposits not detectable
- “Smeared chalk” appearance
- Edema, pneumonia
- Pneumocystis pneumonia
- Pink frothy exudate fills airspaces

13
Q
Atelectasis
- Root “ectasia”
- Aortic ectasia
- Bronchiectasis
- Atelectasis
- Radiologic findings
- Direct
- Indirect
A
- Root “ectasia”: dilation, expansion
- Aortic ectasia - mildly dilated aorta
- Bronchiectasis - bronchial dilatation
- Atelectasis
- Gr. ateles “imperfect” + ektasis “expansion”
- “Collapse” of lung, volume loss
- Radiologic findings
- Direct
- Displaced fissure
- Indirect
- Increased attenuation
- Displaced trachea, hilum, heart, diaphragm
- Hyperinflation of unaffected lung
- Direct

14
Q
Atelectasis: definition
A
- Decreased inflation of a segment, lobe, or lung
- Results in reabsorption of air
- Involved lung has decreased volume, increased opacity
- Due to mucous plug, stricture, tumor, or extrinsic compression of bronchus
- Non-involved lung responds with over
15
Q
Atelectasis
- “Plate-like” atelectasis
- RUL atelectasis
- Lobar atelectasis: RML
A
- “Plate-like” atelectasis
- Subsegmental
- Linear
- RUL atelectasis
- Decreased inflation of segment, lobe, or lung
- Reabsorption of air
- Decreased volume, increased opacity
- Mucous plug, stricture, tumor or compression of bronchus
- Non-involved lung responds with over-inflation
- Lobar atelectasis: RML
- Silhouette sign
- Displaced fissures

16
Q
Atelectasis
- Left lung
- Endobronchial lesions
A
- Left lung
- Heart displaced to left
- R lung is over-inflated
- Endobronchial lesions
- Mucus plugs
- Malpositioned ET tube
- Foreign bodies
- Neoplasms
- Strictures / stenoses

17
Q
Secondary atelectasis
A
- Compressive
- Pleural effusion or PTX
- Huge R effusion
- R lung atelectasis
- Pneumothorax

18
Q
Interstitium
A
- Continuum of loose supporting connective tissue in the lung
- Broncho-arterial
- Acinar - between alveoli and capillaries
- Subpleural - continuous with interlobar septa
- When diseased, tissues surrounding the air spaces & airways are thickened, with preservation of alveolar air
19
Q
Interstitium
- Pulmonary edema
- Pulmonary lobule
A
- Pulmonary edema
- Pulmonary lobule
- Intralobular septa
- Reticulations

20
Q
Alveolar ducts and pulmonary acinus
- Microscopic anatomy
- Fibrosing alveolitis
A
- Microscopic anatomy
- Terminal airways
- Alveolar ducts
- Acini
- Fibrosing alveolitis
- Alveolar collapse
- UIP / IPF

21
Q
Reticulo-nodular pattern
- Reticulo-nodular pattern
- Reticular
- Nodular
- Reticulo-nodular
- Honeycomb
- Nodular pattern
A
- Reticulo-nodular pattern (sarcoid)
- Reticular: interlacing network of fine linear markings that form a mesh & contain air
- Nodular: discrete, punctate, round 1 - 5 mm deposits
- Reticulo-nodular: mixture of interstitial linear thickening & nodular deposits
- Honeycomb: air-containing cystic spaces (5-10 mm) surrounded by thick fibrous walls
- Nodular pattern
- Miliary TB

22
Q
Reticular pattern: differential
A
- Infectious - viruses, PCP
- Immune - scleroderma, hypersensitivity
- Edema
- Inhalational - asbestosis
- Airways - COPD with increased markings, cystic fibrosis (bronchiectasis)
- Drug-induced lung disease
- Pulmonary fibrosis
23
Q
Nodular pattern: differential
A
- Infectious - miliary TB, fungi, CMV
- Non-infectious granulomatous - sarcoid
- Neoplastic - lymphangetic mets, lymphoma
- Inhalational - silicosis
24
Q
Lungs are too black (and too big)
- General
- Emphysema
- Centrilobular emphysema (CLE)
- Centri- and pan-lobular COPD
A
- Retention of excess gas in all or part of lung, especially during expiration
- Oligemia - reduced pulmonary blood flow
- Cardiac: pulmonic stenosis or atresia
- Pulmonary artery HTN
- Large pulmonary embolism
- Over-inflation, air-trapping
- Emphysema
- Abnormally expanded air spaces distal to terminal bronchiole, with destruction of walls of involved air spaces
- Centrilobular emphysema (CLE)
- Punched out black holes
- No perceptible wall
- Pulmonary artery (dot) in center
- Centri- and pan-lobular COPD
- Central airway obstruction
- Small airway diseases
- Emphysema

25
Q
Air trapping
- General
- Panlobular emphysema
- Bronchiectasis
A
- General
- Too big and black
- Retention of excess gas in all or part of lung, especially during expiration
- Due to partial airway obstruction or abnormal pulmonary compliance
- Emphysema: abnormally expanded air spaces distal to terminal bronchiole, with destruction of walls of involved air spaces
- Panlobular emphysema
- Large bulla
- Bronchiectasis
- Dilation
- Mixed pattern

26
Q
Cancer
- Lung transplant
- Lung cancer
- Metastatic sarcoma
- Pulmonary nodule, mass
A
- Lung transplant
- We can live on one lung
- Lung cancer
- Metastatic sarcoma
- Nodules, masses, consolidation
- Pulmonary nodule, mass
- Marble, baseball
- Discrete, circular opacity < 3 cm (T1)
- Arises in lung
- Mass: > 3 cm (T2)
- Solitary vs multiple
- May cavitate

27
Q
Pulmonary nodule or mass: differential
A
- Developmental - AVM, bronchial cyst
- Infectious - TB, fungal (granuloma)
- Neoplastic
- Benign: hamartoma
- Malignant: lung CA, lymphoma, met
- Traumatic - hematoma
- Immunologic - rheumatoid, Wegener’s
28
Q
Normal tracheo-bronchial tree
A

29
Q
Problems
- PET: radioactive glucose
- Cavitary septic emboli (infected)
A
- PET: radioactive glucose
- Cavitary septic emboli (infected)

30
Q
Secondary pulmonary lobule
A
- Building block of the lung
- Unit of lung structure, consists of < 12 acini
- Irregular polyhedral, ~ 1.23 cm
- Marginated by interlobular septa
- Pulmonary veins & lymphatics
- Lobular core
- Pulmonary arteriole & bronchiole
31
Q
Lymph node enlargement: differential
A
- Infectious - TB, fungal
- Non-infectious granulomatous - sarcoid
- Neoplasm - lung CA, lymphoma, mets
- Inhalational - silicosis, berylliosis
- Metabolic - amyloidosis
- Reactive