Nick's Chest Mnemonics
Other Differentials
Approach to Mosaic Lung Attenuation
Situs
- Polysplenia
- Asplenia
Facts
- Types of Bronchiectasis
- False Negative Tumors on PET
Diseases
Lung Cancer Staging
Recommended Followup for Pulmonary Nodules
Features of Solitary Pulmonary Nodules suspicious for malignancy

Nick's Chest Mnemonics

Upper Lobe Interstitial Disease (RadioCASSET)

XRT
Cystic Fibrosis
Ankylosing Spondylitis
Silicosis
Sarcoid
EG
Tuberculosis - post 1°, not miliary (miliary is lower lobe)

Lower Lobe Interstitial Disease (BADAS RIDL)

Bronchiectasis
Aspiration
Drugs (Ritalin, Bleomycin)/Dermatomyositis
Asbestosis
Scleroderma
Rheumatoid
IPF
DIP
Lymphangitic Carcinomatosis

Upper Lobe Predominant Fibrosis

Sarcoidosis
- Upper lung perilymphatic nodules
  - Interlobular
  - Peribronchial
- Coalescent masses secondary to fibrosis
Silicosis/Coal Worker's Pneumoconiosis
- Upper lung nodules
  - Subpleural
  - Centrilobular
- Progressive massive fibrosis (PMF)
- Paracicatricial emphysema
Idiopathic pleuroparenchymal fibroelastosis
- Extensive subpleural and pleural fibrosis
Familial pulmonary fibrosis
- Upper lung or diffuse zonal distribution
Hypersensitivity pneumonitis
- Ground glass
- Air trapping
- Exposure history

Lower Lobe Predominant Fibrosis

Aspiration (mimic)
- Ground-glass or consolidation
- Often dependent
- May be peribronchovascular
- Transient bronchial dilation
Usual interstitial pneumonitis/Idiopathic pulmonary fibrosis
- Subpleural and basilar predominant
- Reticular opacities
- Bronchiolectasis
- Honeycombing
Diffuse pulmonary hemorrhage
- Ground-glass consolidation
- Spares lung periphery
- May progress to fibrosis if recurrent
Nonspecific interstitial pneumonitis
- Ground-glass and reticulation
- Basilar
- Peripheral sparing highly suggestive
- Usually secondary
  - Collagen vascular disease
  - Drugs
  - Chronic hypersensitivity pneumonitis
Organizing pneumonia (not cryptogenic)
- Consolidation
- Transient bronchial dilation
- Reverse halo sign
- Perilobular pattern
- Usually secondary
  - Collagen vascular disease (Myopathies and RA)
  - Aspiration
  - Radiation
  - Drugs
  - Lung or stem cell transplant

Collagen Vascular Disease Patterns in Interstiital Lung Disease

Patterns	Rheumatoid	Scleroderma	PM/DM	Sjogren
UIP	++	++	+	+
NSIP	+	++++	++	+
Organizing Pneumonia	++	+	++	-
Obliterative Bronchiolitis	++	-	-	-
Bronchiectasis	++	-	-	++
LIP	-	-	-	+++

Obliterative Bronchiolitis
- Air trapping
- Mosaic attenuation
- Bronchial wall thickening and dilation
Lymphocytic Interstitial Pneumonitis
- Peribronchovascular cysts
- Pericystic dots

Cysts (LEP LIP)

LAM - uniform cysts
EG (Call it Langerhans Cell Histiocytosis, the chest guys like that) - bizarre cysts w/ small nodules
PCP
LIP
IPF (honeycombing)
Papillomatosis

Bronchiectasis (CIT KAM)

Cystic Fibrosis
Immunodeficiency
- The most common congenital conditions involve B-lymphocyte functions—specifically, hypogammaglobulinemia. An aggressive form of bronchiectasis has been described in patients with acquired immunodeficiency syndrome (AIDS).
Traction
- Associated with pulmonary fibrosis
Kartagener's
ABPA
Mournier-Kuhn/Williams-Campbell (both are lower lobe; Mournier-Kuhn has tracheal widening, Williams-Campbell does not)
Others
- Infection: Typical organisms include Klebsiella species, Staphylococcus aureus, Mycobacterium tuberculosis, Mycoplasma pneumoniae, nontuberculous mycobacteria, Mycobacterium avium-intracellulare complex, measles, pertussis, influenza, respiratory syncytial virus, herpes simplex virus, and certain types of adenovirus.
- Bronchial obstruction: Obstruction occurs as a result of endobronchial tumors, broncholithiasis, bronchial stenosis resulting from infections, encroachment of hilar lymph nodes, and foreign body aspiration.
- Young syndrome
- Alpha-1 Antitrypsin deficiency
- Lung and bone marrow transplants
- Rheumatoid arthritis and Sjögren syndrome
- Bronchopulmonary sequestration
- Swyer-James syndrome (unilateral hyperlucent lung)
- Yellow nail syndrome

Patchy Peripheral Airspace Disease (RRECH DB)

Resolving Edema
Resolving Multifocal PNA
Eosinophilic Pneumonia/Loffler's
COP (has peripheral clear zone)
Hypersensitivity Pneumonitis
Drug Toxicity
Bronchioloalveolar CA

Cavitary Lesions (CAVITY)

Carcinoma (SCC, colon, TCC, sarcoma, melanoma, cervical)
Autoimmune (Rheumatoid, Wegeners)
Vascular
Infection (abscess, fungal, TB, echinococcus)
Trauma
Young (congenital)

Crazy Paving (PEPPAH)

Pulmonary Alveolar Proteinosis
Edema
PCP
Pneumonia
ARDS
Hemorrhage

Miliary Pattern (FAT SPAM)

Fungal
Amyloid
TB
Sarcoid
Pneumoconiosis
Alveolar Microlithiasis
Mets (ThRAB - thyroid, renal cell, any adenoCA, breast)

Pleural Mets (GIBT)

GI Adenocarcinomas
Breast
Thymoma

Other Differentials

Chronic Patchy Consolidation

BAC
Lymphoma
Eosinophilic Pneumonia
COP
Sarcoid
Infarct
Metastatic Pulmonary Calcification
TB
Lipoid Pneumonia
Pulmonary Alveolar Proteinosis

Tree-In-Bud

Endobronchial Spread of Infection (esp TB)
Bronchiolitis
Viral/Fungal Infection
ABPA
Aspiration
Atypical Mycobacteria
Mycoplasma

Reverse Batwing

Loffler's
Parasitic Infection

Air Crescent Sign

Aspergilloma
Echinococcus

Honeycombing

IPF
Collagen Vascular Disease
Asbestosis
Drugs

Unilateral Pulmonary Edema

Reexpansion Edema
Gravity
Mass Obstructing Pulmonary Veins
Large Contralateral PE

Solitary Pulmonary Metastasis

Colon
Sarcomas
Renal Cell
Testicular
Breast
Melanoma

Cannonball Lesions

Mets
- Renal Cell
Lymphoma
Sarcoid

Mets Causing Bilateral Hilar Adenopathy

Renal Cell
Melanoma
Breast
GU Tumors

Centrilobular Nodules

Hypersensitivity Pneumonitis
RB-ILD
TB/Atypical Infection
LIP
Sarcoid

Peribronchovascular Nodules

Sarcoid
Lymphangitic Carcinomatosis
Lymphoma
Kaposi's Sarcoma
Plus Tree-In-Bud DDx

Endobronchial Masses

Carcinoid
Adenoid Cystic CA
Mucoepidermoid CA
Papilloma
Fibrous tumors
Leiomyomas
Neurofibromas
SCC (trachea)

Endobronchial Mets

Breast
Renal
Melanoma

Causes of Diffuse Pulmonary Hemorrhage

Immune-mediated
- antiglomerular basement membrane antibody disease (Goodpasture syndrome)
- systemic lupus erythematosus (SLE)
- Wegener granulomatosis
- immune complex disease
- polyarteritis nodosa
- rheumatoid arthritis
- Henoch-Schonlein purpura
Non-immune
- idiopathic pulmonary hemorrhage (IPH)
- coagulopathies
- drugs (penicillamine)

Causes of Hypertrophic Pulmonary Osteoarthropathy

Pulmonary Neoplasm (Benign or Malignant)
Chronic Infection (CF, TB)
R → L Shunt
Congenital Heart Disease

Cardiac Mets

Lung
Breast
Melanoma
Lymphoma

Lymphangitic Mets

Lung
Breast
Gastric
Pancreatic
Esophageal

Causes of Pulmonary Edema

Cardiogenic

LV failure
mitral valve dz
pulmonary venous occlusion
pericardial dz
beta blockers

Non-cardiogenic

Renal Failure
Fat Emboli
Neurogenic
Sepsis
Volume Overload
Hypoproteinemia
Increased Capillary Permeability
- Aspiration
- Near-drowning
- Anaphylaxis

Diffuse Tracheal Narrowing

COPD (saber sheath trachea)
radiation Δ
Tracheobronchopathia Osteochondroplastica
Relapsing Polychondritis
Tracheomalacia

Chronic Consolidation

COP
Eosinophilic PNA
Lymphoma
Bronchioloalveolar CA

Halo Sign

Hemorrhagic Mets
- Kaposi's
- Renal Cell
- Choriocarcinoma
Invasive Aspergillus

Chest Wall Mass

Benign
- Lipoma
- Fibrous Tumor of Pleura
- Desmoid
- Hemangioma
- Pleural Plaque (i.e. asbestos related pleural disease)
- Trauma with hematoma
Malignant
- Mets
- Chondrosarcoma
- Liposarcoma
- Leiomyosarcoma
- MFH/Fibrosarcoma
- Neurogenic Tumors
Infectious
- Staph
- TB
- Actinomycosis
- Nocardia

Vascular Rings

Pulmonary Sling → L pulm art travels behind trachea
Right Arch w/ Aberrant L Subclavian

Approach to Mosaic Lung Attenuation

Perform expiratory CT → Is there air trapping?

Yes → Small Airway Disease (CHABB)
- Cystic Fibrosis
- Hypersensitivity Pneumonitis
- Asthma
- Bronchiolitis
- Bronchiolitis Obliterans/Obliterative Bronchiolitis
No → Compare Vessel Disease
- Equal → Ground Glass Abnormal
  - Hemorrhage
  - PCP
  - NSIP/DIP
  - Hypersensitivity Pneumonitis
  - Edema
  - ARDS
  - Bronchioloalveolar CA
  - Pulmonary Alveolar Proteinosis
- Ground Glass Vessels Large/Dark Vessels Small → Dark Areas Abnormal
  - Chronic PE
  - Pulmonary HTN

Situs

Solitus = normal
Inversus = everything inverted; asymptomatic
Ambiguous = L cardiac apex, R stomach

Polysplenia

Multiple spleens
Bilateral L-sidedness
No IVC; azygous continuation

Asplenia

No spleen
Bilateral R-sidedness
Bilateral liver

Facts

Interlobular Septa = Kerley B lines
Intralobular Septa = reticular lines
Shaggy Heart Sign = Interstitial Lung Disease
Semisolid Lesion suggests Bronchioloalveolar CA
Aortic Nipple = L Superior Intercostal Vein
Azygous Line Placement = High Risk of Rupture
Luftsickle Sign = LUL Collapse
- lucent crescent representing SS LLL
Abnormal Rotation of Heart → Think Congenital Absence of Pericardium
Don't forget the relationship b/w osteosarcoma mets and PTX

Types of Bronchiectasis

Cylindrical → bronchi are minimally dilated and straight and regular
- CXR will show tram tracking or ring shadows in the distribution of bronchi
Varicose → string of pearls, with alternating dilation and narrowing
Cystic → a cluster of cysts ± air fluid levels

False Negative Tumors on PET

BAC
mucinous tumors
GI mets

Diseases

Legionella Pneumonia

begins w/ large, focal, ill-defined opacity
progresses to bilateral lung involvement w/i first few days
pleural effusion may be present (30-60%)
cavitation and lymphadenopathy are rare

Hypersensitivity Pneumonitis

acute → lower lobe consolidation
subacute → upper lobe nodules
chronic → upper lobe interstitial fibrosis

Causes of Emphysema

Smoking
Chronic Fibrosis
XRT

Metastatic Pulmonary Calcification

Associated with ESRD
Looks like edema on CXR
MDP bone scan shows extensive uptake

Mediastinal Fibrosis

also known as chronic fibrosis, fibrosing mediastinitis, chronic mediastinal fibrosis, or cryptogenic mediastinal fibrosis
histoplasmosis is the most common cause
can cause SVC obstruction

Churg-Strauss

Eosinophilia
Severe Asthma
Systemic Vasculitis

Hepatopulmonary Syndrome

Triad of
1. Chronic liver disease
2. Increased alveolar-arterial oxygen gradient on room air
3. Intrapulmonary arteriovenous shunting

Carney's Triad

pulmonary chondroma
gastric leiomyosarcoma
extra-adrenal paraganglioma

Cowden's Disease

pulmonary and GI hamartomas
multiple mucocutaneous lesions

Lung Cancer Staging

Tumor

T1 <3 cm, limited to lung
T2 >3 cm, >2 cm distal to carina
T3 any size, direct extension into chest wall, superior sulcus, diaphragm, pleura, pericardium, or within 2 cm of carina
T4 mediastinal (heart, great vessels, esophagus), carinal, brachial plexus, vertebral body invasion or malignant pleural effusion → unresectable

Nodes

N0 no LN involvement
N1 ipsilateral hilar nodes
N2 ipsilateral mediastinal or subcarinal nodes
N3 contralateral hilar or mediastinal nodes; supraclavicular nodes → unresectable

Mets

M0 none
M1 distant mets → unresectable

Important Stages

Tumor unresectable if T4, N3, or M1
Stage 3b
- N3, M0, any T
- T4, M0, any N
Stage 4
- M1, any T, any N

Recommended Followup for Pulmonary Nodules

Fleischner Society Criteria

Nodule Size	Low-Risk Patient	High-Risk Patient
< 4 mm	No follow-up needed	Follow-up CT at 12 mo; if unchanged, no further follow-up
4-6 mm	Follow-up CT at 12 mo; if unchanged, no further follow-up	Initial follow-up CT at 6-12 mo then at 18-24 mo if no change
6-8 mm	Initial follow-up CT at 6-12 mo then at 18-24 mo if no change	Initial follow-up CT at 3-6 mo then at 9-12 and 24 mo if no change
> 8 mm	Follow-up CT at around 3, 9, and 24 mo, dynamic contrast enhanced CT, PET, and/or biopsy	Same as for low-risk patient

Features of Solitary Pulmonary Nodules suspicious for malignancy

Microlobulated or spiculated margins
Bubbly or cystic lucencies; air bronchograms
Mixed ground glass/solid attenuation; subsolid (mixed attenuation)
Airway component
Relatively rapid growth

* Recommend biopsy or resection in pts with moderate to high risk of lung CA or solitary metastasis

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