Thoracic Flashcards
Interlobular fissures
Minor: RUL from RML (seen on frontal and lateral)
Major: only on lateral
Azygos: accessory RUL apical or posterior are encased
Atelectasis
Collapse
Direct: fissure displacement/ vascular crowding
Indirect: diaphragm elevation/rib crowding/ mediastinal shift/ overinflation of contralateral lobe/hilar displacement
Central bronchial obstruction: no air bronchogram
Subsegmental: air bronchogram
Obstructive atelectasis
Bronchial obstruction Lobar More quickly in patient with supplemental O2 Imaging: volume loss ICU patient: consolidation
Obstructive atelectasis in peds
Foreign body
Hyperexpanded
Subsegmental atelectasis
After surgery
General illness
Mucus obstruction
Relaxation atelectasis
Adjacent to a lesion causing mass effect
Pleural effusion
Pneumothorax
Pulmonary mass
Adhesive atelectasis
Surfactant deficiency
NRDS
ARDS
Cicatricial atelectasis
Architectural distortion by fibrosis
Lobar atelectasis
Central bronchial obstruction Mucus plugging (acute) Neoplasm (chronic)
LUL atelectasis
Luftsichel sign
Crescent of air ( between aorta and hyperexpanded superior LLL)
RUL atelectasis
Reverse S sign of golden
suspicious for malignancy
Juxtaphrenic peak sign: traction of inf accessory fissure
LLL atelectasis
Triangular retrocardiac opacity
Loss of left heart border
Left hilum down
Flat waist sign
RLL atelectasis
Mirror of LLL collapse
Wedge shaped retrocardiac opacity
RML atelectasis
Silhouetting of right heart border
Lateral view: wedge shape opacity anteriorly
Round atelectasis
Focal Always with adjacent pleural abnormalities Common: posterior lower lobes 1. Abnormal pleura 2.peripheral opacity 3. Round opacity 4. Volume loss 5. Curved pulmonary vessels and bronchi( comet tail sign)
Secondary pulmonary nodule
Central artery—> acinar artery
Central bronchus—> respiratory bronchioles
Vein and lymphatic—> periphery
Interlobular septa encases SPL
12 acini per SPL
Consolidation an ground glass
Abnormal alveoli
GG—> only on CT
Consolidation
Filling of alveoli with liquid
Vessels are not visible
Air bronchogram
Acute consolidation
Pneumonia
Hemorrhage
ARDS ( non carcinogenic pulmonary edema)
Pulmonary edema
Chronic consolidation
Bronchioalveolar carcinoma ( mucinous subtype) Organizing pneumonia ( granulation polyps) Chronic eosinophilic pneumonia ( upper lobe distribution)
Ground glass opacification
Partial filling of alveoli
Wall thickening
Atelectasis
Acute ground glass
Pulmonary edema
Pneumonia (atypical)
Hemorrhage
ARDS
Chronic ground glass
Bronchioalveolar carcinoma
Organizing pneumonia ( round/ peripheral)
Chronic eosinophilic pneumonia ( upper lobe)
Idiopathic pneumonia
Hypersensitivity pneumonitis ( type 3)
Alveolar proteinosis ( central sparing of periphery)
Central ground glass opacity
Pulmonary edema
Alveolar hemorrhage
Pneumocystis jiroveci pneumonia
Alveolar proteinosis
Peripheral ground glass
Organizing pneumonia
Chronic eosinophilic pneumonia ( upper lobes)
Atypical/viral pneumonia
Pulmonary edema ( non cardiogenic)
Smooth interlobular septal thickening
Pulmonary vein dilation: Pulmonary edema Pulmonary alveolar proteinosis Pulmonary hemorrhage Atypical pneumonia
Nodular interlobular septal thickening
Infiltration of peripheral lymphatic:
Lymphangitic carcinomatosis
Sarcoidosis (noncaseating granulomas)
Crazy paving
Interlobular septal thickening plus ground glass opacification Alveolar proteinosis Pneumocystis jiroveci pneumonia Organizing pneumonia Bronchioalveolar carcinoma (mucinous) Lipoid pneumonia ARDS Pulmonary hemorrhage
Centrilobular nodules
Opacification of centrilobular bronchiole
CT: multiple small nodules , never extend to the pleura
Infection: atypical mycobacteria ( MAC), endobronchial spread of TB
Bronchopneumonia, atypical pneumonia
Inflammation: hypersensitivity pneumonitis (subacute) , respiratory bronchialitis interstitial lung disease, hot tub lung, diffuse panbronchiolitis ( lymphoid hyperplasia, Asians) , silicosis ( upper lobe, perlymphatic nodules)
Perilymphatic nodules
Subpleural, peribronchovascular, septal
Sarcoidosis (upper lobe, galaxy sign)
Pneumoconioses
Lymphangitic carcinomatosis
Random nodules
Hematogenous metastasis Septic emboli (cavitate) Pulmonary langerhan’s cell histiocytosis (smoking/ random nodule—>irregular cyst)
Miliary pattern—>disseminated TB, fungal infection, hematogenous metastases
Tree in bud nodules
Small airways infection
Mycobacteria TB and atypical mycobacteria
Bacterial pneumonia
Aspiration pneumonia
Airway invasive aspergillus ( immunocompromised)
Solitary cavitary
wall thickness<4mm is benign >15 mm malignant
Primary bronchogenic carcinoma (squamous more than adenocarcinoma)
TB—> upper lobe
Multiple cavitary nodules
Septic emboli
Vasculitis ( Wegener)
Metastases (squamous cell carcinoma and uterine carcinosarcoma)
Multiple Cystic lung disease
Lymphangioleiomyomatosis (LAM)—> diffuse with chylous effusion
Emphysema—>upper lobes, smokers
PLCH—>cyst+nodules—> upper lobes
Diffuse cystic bronchiectasis : upper—> cystic fibrosis / diffuse or lower—> congenital or post infectious
Pneumocystis jiroveci pneumonia
Lymphoid interestitial pneumonia—> Sjogren / alveolar distortion
Single cyst lung disease
Bulla
Bleh —> continguous with pleura <1cm ( rupture—> spontaneous pneumothorax)
Pneumatocele—>prior lung trauma or infection
Lower lobe fibrotic changes
Idiopathic pulmonary fibrosis —> bibasilar fibrosis, basilar honeycombing
End stage asbestosis—> pleural plaques
Nonspecific interestitial pneumonia (NSIP)—> collagen vascular disease or drug reaction/ cellular and fibrotic form/ basal fibrosis, no honeycombing
Upper lobe fibrotic changes
End stage sarcoidosis
Chronic hypersensitivity pneumonitis
End stage silicosis
Community acquired pneumonia
S. Pneumonia
Mycoplasma—> varied appearance
Legionella—> elderly patients / peripheral progress to lobar and multi focal
Klebsiella—> alcoholics and aspiration/ voluminous/bulging fissure
Hospital acquired pneumonia (HAP)
MRSA
Pseudomonas
Health care associated pneumonia
Nursing homes
>2 days hospitalization
Similar to HAP
Ventilator associated pneumonia
Mechanical ventilator
Polymicrobial
Pseudomonas
Acinetbacter
Pneumonia in immunocompromised
Pneumocystis
Aspergillus
Nocardia
CMV
Lobar pneumonia
Bacterial
Most common CAP
air bronchogram
Lobular pneumonia
Patchy consolidation
Poor defined airspace opacity
S. Aureus
Interstitial pneumonia
Inflammatory cells in interstitial tissue
Diffuse patchy or GG
viral , mycoplasma, chlamydia, pneumocystis
Round pneumonia
Children
Streptococcus pneumoniae
Due to incomplete formation of pores of Kohn
Pulmonary Abscess
Staph aureus, pseudomonas, anaerobics
Air-fluid level
Spherical
Pulmonary gangrene
Extensive necrosis and sloughing
Empyema
Pleural space
- Free flowing exudative effusion—> aspiration
- Development of fibrous strands—> large bore chest tube and fibrinolytic
- Solid and jelly like—> surgery
Split pleura sign—> enhancing parietal and visceral pleura
DDx: malignant effusion, mesothelioma,fibrothorax,talc pleurodesis
Pneumatocele
Thin walled, gas filled
Post traumatic, sequela of pneumonia ( Staph aureus, pneumocystis)
Bronchopleural Fistula
Rupture of visceral pleura
Surgery common cause
Lung abscess, empyema, trauma
New or increasing gas in pleural effusion
Empyema necessitans
Extension of empyema to chest wall
Secondary to TB
Nocardia, actinomyces
TB exposure
- Contained (90%)—> calcified granulomas, calcified hilar lymph node
- Primary tuberculosis—> children, immunocompromised
- Reactivation
Primary tuberculosis
15%—> no radiologic sign
Imaging: ill-defined consolidation, pleural effusion, lymphadenopathy, miliary
Lower lobes or RML
Ghon focus—> focus of parenchymal infection upper of lower lobe or lower of upper lobe
Ranke complex—> Ghon + LAP
Adenopathy—> common, central hypo and peripheral enhancement
cavitation is rare in primary TB
Reactivation TB
Adolescents and adults
Upper lobe apical and posterior segments
Immunocompetent—> cavitation and no adenopathy
Tree in the bud—> active endobronchial spread
Immunocompromised—> hypo adenopathy
Tuberculoma—> round opacity in upper lobes
Healed TB
Apical scarring
Upper lobe volume loss
Superior hilar retraction
Calcified granulomas ( delayed hypersensitivity)
Miliary TB
Diffuse random nodules
Disseminated TB
Atypical mycobacterial infection
Elderly woman with cough, fever, weight loss
Mycobacterium Avium intercellulare, M. Kansas I
Imaging: bronchiectasis, tree in bud, RML and lingula
Hut tub lung
Hypersensitivity pneumonitis
Centrilobular nodules
Histoplasma capsulatum
Ohio, Mississippi
Bat, bird guano
Calcified granulomas , pulmonary nodules
Chronic—> similar to TB, upper lobes fibrocavitary consolidation
Fibrosing mediastinitis—> pulmonary venous obstruction, bronchial stenosis, pulmonary artery stenosis, calcified lymph nodes
Coccidiodes immitis and blastomyces dermatitidis
Coccidiodes immitis: southwest, multifocal consolidation,multiple pulmonary nodules, miliary nodules
Blastomyces dermatitidis: central, southeast, multifocal consolidation, ARDS, miliary disease
Pneumocystis jiroveci pneumonia
CD4<200
Bilateral perihilar airspace opacities with peripheral sparing
CT—> perihilar GG opacification, crazy paving
Upper lobe pneumatoceles —> pneumothorax, pneumomediastinum
Cryptococcus neoformans
Most common in AIDS
GG, focal consolidation, cavitating nodules
Miliary with LAP or effusion
ABPA
Hypersensitivity to aspergillus
Long standing asthma
CT—> upper lobes bronchiectasis, mucoid impaction, hyper or calcified (finger in glove)
DDx—> CF
Aspergilloma
Mycetoma or fungus ball in pre existing pulmonary cavity
Mobile
Monod sign—> crescent of air outlining the mycetoma
Semi invasive aspergillosis
Necrotizing granulomatous inflammation
Diabetic, alcoholic, debilitated, COPD
Segmental consolidation, cavitation, pleural thickening
Airway invasive aspergillosis
Airway epithelial cells
Neutropenic and AIDS
Bronchiolitis, bronchopneumonia
CT—> centrilobular and tree in bud nodules
Angioinvasive aspergillosis
Severely immunocompromised
CT—> halo: GG around consolidation/ DDx: viral, Wegener, Kaposi, metastasis
Air crescent—> good prognostic sign
Pulmonary edema
Increased pulmonary vein
- Vascular redistribution: increased caliber of upper lobe vessels
- Interstitial edema: increased interstitial marking, indistinctness of pulmonary vasculature, peribronchial cuffing, Kerley B ( peripheral) and A (radiates from hila)
- Alveolar edema: central opacification, pleural effusion, cardiomegaly
Pulmonary edema on CT
Dependent GG
Interlobular septal thickening
HF—> patchy GG
Sepsis, low protein—> diffuse GG
RUL pulmonary edema—> acute mitral regurgitation
Aggressive thoracentesis—> reexpansion pulmonary edema
Vascular pedicure
Width of upper mediastinum —> < 58 mm
>63 or 70–> increases pulmonary capillary wedge pressure(>18) and fluid overload
Right border—> interface of SVC and right main bronchus
Left border—> lateral of subclavian origin from aorta
Endotracheal tube
4-6 cm above carina
Right bronchus direct intubation is more common—>
Complete atelectasis of un intubated lung
Central venous catheter
Tip in lower SVC or CA junction
Azygos malposition—> venous perforation, thrombosis
Dialysis catheter in right atrium
Pulmonary artery catheter
Tip in main , right, left pulmonary artery
If distal to proximal interlobar pulmonary artery—> rupture, pseudoaneurysm, intra cardiac catheter knot and arrhythmia
Lung cancer risk factors
Smoking—> SCC, small cell carcinoma
Berryllium, radon,arsenic,asbestos
Pulmonary fibrosis
Pulmonary scarring
