hrct of common lung diseases w. richard webb md. common lung diseases: hrct infections (pneumonia,...

HRCT of CommonHRCT of CommonLung DiseasesLung Diseases

W. Richard Webb MDW. Richard Webb MD

Common Lung Diseases: HRCTCommon Lung Diseases: HRCTCommon Lung Diseases: HRCTCommon Lung Diseases: HRCT

• Infections (pneumonia, airways disease)Infections (pneumonia, airways disease)

• SarcoidosisSarcoidosis

• Hypersensitivity pneumonitisHypersensitivity pneumonitis

• UIP and idiopathic pulmonary fibrosis (IPF)UIP and idiopathic pulmonary fibrosis (IPF)

• Nonspecific interstitial pneumonia (NSIP)Nonspecific interstitial pneumonia (NSIP)

• Organizing pneumonia (OP or BOOP)Organizing pneumonia (OP or BOOP)

• Infections (pneumonia, airways disease)Infections (pneumonia, airways disease)

• SarcoidosisSarcoidosis

• Hypersensitivity pneumonitisHypersensitivity pneumonitis

• UIP and idiopathic pulmonary fibrosis (IPF)UIP and idiopathic pulmonary fibrosis (IPF)

• Nonspecific interstitial pneumonia (NSIP)Nonspecific interstitial pneumonia (NSIP)

• Organizing pneumonia (OP or BOOP)Organizing pneumonia (OP or BOOP)

SarcoidosisSarcoidosisSarcoidosisSarcoidosis

• microscopic noncaseating granulomas in clustersmicroscopic noncaseating granulomas in clusters

• 60-70% have characteristic plain film findings60-70% have characteristic plain film findings

• 10% have normal chest radiographs10% have normal chest radiographs

• HRCT abnormal in most with normal radiographsHRCT abnormal in most with normal radiographs

• microscopic noncaseating granulomas in clustersmicroscopic noncaseating granulomas in clusters

• 60-70% have characteristic plain film findings60-70% have characteristic plain film findings

• 10% have normal chest radiographs10% have normal chest radiographs

• HRCT abnormal in most with normal radiographsHRCT abnormal in most with normal radiographs

• small nodules, usually well-defined are typicalsmall nodules, usually well-defined are typical

• patchy distributionpatchy distribution

• upper lobe predominance in mostupper lobe predominance in most

• the nodules show a “perilymphatic” distributionthe nodules show a “perilymphatic” distribution

• typical lymph node enlargement or calcification in typical lymph node enlargement or calcification in some patients is suggestive, but is not necessary some patients is suggestive, but is not necessary for diagnosisfor diagnosis

• small nodules, usually well-defined are typicalsmall nodules, usually well-defined are typical

• patchy distributionpatchy distribution

• upper lobe predominance in mostupper lobe predominance in most

• the nodules show a “perilymphatic” distributionthe nodules show a “perilymphatic” distribution

• typical lymph node enlargement or calcification in typical lymph node enlargement or calcification in some patients is suggestive, but is not necessary some patients is suggestive, but is not necessary for diagnosisfor diagnosis

Sarcoidosis: HRCT findingsSarcoidosis: HRCT findingsSarcoidosis: HRCT findingsSarcoidosis: HRCT findings

• perilymphatic nodules predominate in relation to perilymphatic nodules predominate in relation to the peripheral pleural surfaces and fissures, the peripheral pleural surfaces and fissures, and the peribronchovascular interstitiumand the peribronchovascular interstitium

• interlobular septal nodules are less frequent and interlobular septal nodules are less frequent and less numerousless numerous

• centrilobular nodules can be seen involving the centrilobular nodules can be seen involving the centrilobular peribronchovascular interstitiumcentrilobular peribronchovascular interstitium

• in rare patients, the nodules appear random in in rare patients, the nodules appear random in distributiondistribution

• perilymphatic nodules predominate in relation to perilymphatic nodules predominate in relation to the peripheral pleural surfaces and fissures, the peripheral pleural surfaces and fissures, and the peribronchovascular interstitiumand the peribronchovascular interstitium

• interlobular septal nodules are less frequent and interlobular septal nodules are less frequent and less numerousless numerous

• centrilobular nodules can be seen involving the centrilobular nodules can be seen involving the centrilobular peribronchovascular interstitiumcentrilobular peribronchovascular interstitium

• in rare patients, the nodules appear random in in rare patients, the nodules appear random in distributiondistribution

Sarcoidosis: NodulesSarcoidosis: NodulesSarcoidosis: NodulesSarcoidosis: Nodules

Sarcoidosis

Subpleural and peribronchovascular nodules

.

Perilymphatic nodules in sarcoidosis:peribronchovascular and subpleural

.

Perilymphatic nodules in sarcoidosis:peribronchovascular and subpleural

.

Perilymphatic nodules in sarcoidosis:peribronchovascular and subpleural

Sarcoidosis: interlobular septal nodules.

. Sarcoidosis with interlobular septal nodules

interlobular septal noduleswith atypical basal

distribution

.

.

Centrilobular (peribronchovascular) nodules

.

Sarcoidosis:centrilobular opacitiesmimicking tree-in-bud

Sarcoidosis:centrilobular nodules

.

Sarcoidosis:nodules with a

“random”distribution

• large nodules or masses - 15-25%large nodules or masses - 15-25%» often upper lobe, parahilar » often upper lobe, parahilar

(peribronchovascular) (peribronchovascular) » air bronchograms (i.e. consolidation)» air bronchograms (i.e. consolidation)» confluence of granulomas» confluence of granulomas» satellite nodules (“galaxy sign”)» satellite nodules (“galaxy sign”)» “alveolar sarcoid”» “alveolar sarcoid”

• ground-glass opacityground-glass opacity» confluence of small granulomas» confluence of small granulomas

• large nodules or masses - 15-25%large nodules or masses - 15-25%» often upper lobe, parahilar » often upper lobe, parahilar

(peribronchovascular) (peribronchovascular) » air bronchograms (i.e. consolidation)» air bronchograms (i.e. consolidation)» confluence of granulomas» confluence of granulomas» satellite nodules (“galaxy sign”)» satellite nodules (“galaxy sign”)» “alveolar sarcoid”» “alveolar sarcoid”

• ground-glass opacityground-glass opacity» confluence of small granulomas» confluence of small granulomas

Sarcoidosis: additional findingsSarcoidosis: additional findingsSarcoidosis: additional findingsSarcoidosis: additional findings

Sarcoidosis: subpleural and

peribronchovascular nodules

confluent nodules:masses with satellites

.

.

Sarcoidosis: subpleural and

peribronchovascular nodules

confluent nodules:masses with satellites

.

confluent nodules:masses with satellites

the “galaxy sign”

Sarcoidosis: subpleural and

peribronchovascular nodules

.

confluent nodules: masses with satellites

.

Sarcoidosis: confluent nodules withair bronchograms

Sarcoidosis: confluent nodules withair bronchograms

.

Sarcoidosis: clustered small nodules with satellitesand ground-glass opacity

Sarcoidosis: nodules and

ground-glass opacity

.

Sarcoidosis: ground-glass opacity

.

• obstruction of large airwaysobstruction of large airways

• endobronchial granulomasendobronchial granulomas

• small airway obstruction with mosaic perfusion small airway obstruction with mosaic perfusion and/or air trapping on expiratory scansand/or air trapping on expiratory scans

• obstruction of large airwaysobstruction of large airways

• endobronchial granulomasendobronchial granulomas

• small airway obstruction with mosaic perfusion small airway obstruction with mosaic perfusion and/or air trapping on expiratory scansand/or air trapping on expiratory scans

Sarcoidosis: airway abnormalitiesSarcoidosis: airway abnormalitiesSarcoidosis: airway abnormalitiesSarcoidosis: airway abnormalities

Sarcoid: airway abnormalities

45 year oldwith dyspnea

bronch: sarcoidosis.

1 year later

.

dynamic expiration

Sarcoidosis: nodules andair trapping

.

.

Sarcoidosis: subpleural and

peribronchovascular nodules

.

dynamic expiration

Sarcoidosis: air trapping

inspiration

.

dynamic expiration

Sarcoidosis: air trapping

Sarcoidosis: late or fibroticSarcoidosis: late or fibroticSarcoidosis: late or fibroticSarcoidosis: late or fibrotic

• nodules decrease (but often remain visible)nodules decrease (but often remain visible)

• distortion of fissures, reticulationdistortion of fissures, reticulation

• interlobular septal thickeninginterlobular septal thickening

• peribronchovascular fibrosis, usually upper lobeperibronchovascular fibrosis, usually upper lobe

• conglomerate masses of fibrous tissueconglomerate masses of fibrous tissue

• traction bronchiectasistraction bronchiectasis

• subpleural honeycombing in a few percentsubpleural honeycombing in a few percent

• emphysema and cystsemphysema and cysts

• nodules decrease (but often remain visible)nodules decrease (but often remain visible)

• distortion of fissures, reticulationdistortion of fissures, reticulation

• interlobular septal thickeninginterlobular septal thickening

• peribronchovascular fibrosis, usually upper lobeperibronchovascular fibrosis, usually upper lobe

• conglomerate masses of fibrous tissueconglomerate masses of fibrous tissue

• traction bronchiectasistraction bronchiectasis

• subpleural honeycombing in a few percentsubpleural honeycombing in a few percent

• emphysema and cystsemphysema and cysts

Sarcoidosis: early fibrosis withreticulation and

distortion of fissures

.

.

Sarcoidosis: fibrosis with reticulation andseptal thickening

Sarcoidosis: conglomerate fibrosis,

traction bronchiectasis,posterior displacement

of the hila

.

Sarcoidosis: fibrosis with

traction bronchiectasis

.

.

Sarcoidosis: peribronchovascular

fibrosis withtraction bronchiectasis,

mild honeycombing

Sarcoidosis: traction bronchiectasis

and cysts

.

Sarcoidosis: traction bronchiectasis

and cysts

.

.

Sarcoidosis: fibrosis with cysts

.

Sarcoidosis: traction bronchiectasis,

cysts, emphysema,aspergilloma

Sarcoidosis: traction bronchiectasis

and honeycombing

.

HypersensitivityPneumonitis

Hypersensitivity Pneumonitis (HP)Hypersensitivity Pneumonitis (HP)Hypersensitivity Pneumonitis (HP)Hypersensitivity Pneumonitis (HP)

• commoncommon

• caused by inhalation of organic antigenscaused by inhalation of organic antigens

• responsible antigen identified in only 50%responsible antigen identified in only 50%

• acute, subacute, and chronic stagesacute, subacute, and chronic stages

• repeated exposures produce fever, chills, dry repeated exposures produce fever, chills, dry cough, dyspneacough, dyspnea

• progressive symptoms over months or yearsprogressive symptoms over months or years

• commoncommon

• caused by inhalation of organic antigenscaused by inhalation of organic antigens

• responsible antigen identified in only 50%responsible antigen identified in only 50%

• acute, subacute, and chronic stagesacute, subacute, and chronic stages

• repeated exposures produce fever, chills, dry repeated exposures produce fever, chills, dry cough, dyspneacough, dyspnea

• progressive symptoms over months or yearsprogressive symptoms over months or years

• ongoing exposureongoing exposure

• progressive symptoms over weeks to monthsprogressive symptoms over weeks to months

• ill-defined peribronchiolar granulomasill-defined peribronchiolar granulomas

• alveolitis and interstitial infiltrationalveolitis and interstitial infiltration

• cellular bronchiolitiscellular bronchiolitis

• ongoing exposureongoing exposure

• progressive symptoms over weeks to monthsprogressive symptoms over weeks to months

• ill-defined peribronchiolar granulomasill-defined peribronchiolar granulomas

• alveolitis and interstitial infiltrationalveolitis and interstitial infiltration

• cellular bronchiolitiscellular bronchiolitis

Hypersensitivity Pneumonitis: subacute stageHypersensitivity Pneumonitis: subacute stageHypersensitivity Pneumonitis: subacute stageHypersensitivity Pneumonitis: subacute stage

• ill-defined centrilobular nodules (50-60%),ill-defined centrilobular nodules (50-60%),usually of ground-glass opacity (granulomas)usually of ground-glass opacity (granulomas)

• patchy ground-glass opacity (75-90%) (alveolitis)patchy ground-glass opacity (75-90%) (alveolitis)

• patchy mosaic perfusion; air trapping on patchy mosaic perfusion; air trapping on expiratory scans (bronchiolitis) expiratory scans (bronchiolitis)

• diffuse or predominant in mid lung zones; diffuse or predominant in mid lung zones; entire cross section of lung involved; entire cross section of lung involved; no subpleural predominanceno subpleural predominance

• a few lung cysts in a few patientsa few lung cysts in a few patients

• ill-defined centrilobular nodules (50-60%),ill-defined centrilobular nodules (50-60%),usually of ground-glass opacity (granulomas)usually of ground-glass opacity (granulomas)

• patchy ground-glass opacity (75-90%) (alveolitis)patchy ground-glass opacity (75-90%) (alveolitis)

• patchy mosaic perfusion; air trapping on patchy mosaic perfusion; air trapping on expiratory scans (bronchiolitis) expiratory scans (bronchiolitis)

• diffuse or predominant in mid lung zones; diffuse or predominant in mid lung zones; entire cross section of lung involved; entire cross section of lung involved; no subpleural predominanceno subpleural predominance

• a few lung cysts in a few patientsa few lung cysts in a few patients

Hypersensitivity Pneumonitis: subacute stageHypersensitivity Pneumonitis: subacute stageHypersensitivity Pneumonitis: subacute stageHypersensitivity Pneumonitis: subacute stage

.

Subacute hypersensitivity pneumonitis

.

Subacute hypersensitivity pneumonitis

.

Subacute hypersensitivity pneumonitis

.

.

Subacute hypersensitivity pneumonitis

Subacute HP:patchy GGO

post-treatment

Hypersensitivitypneumonitis

ground-glassopacity

.

.

ground-glass opacity + mosaic perfusion

“Headcheese sign”

ground-glass opacity = interstitial infiltrationmosaic perfusion = bronchiolitis

Hypersensitivity pneumonitis

Headcheese sign

.

lobular (geographic)ground-glass opacityand mosaic perfusion

(air trapping)

indicative of mixedinfiltrative diseaseand bronchiolitis

Headcheese sign

Hypersensitivity Pneumonitis

mosaic perfusion.

expiration.

66 year old bird fancier with progressive dyspnea

Hypersensitivity pneumonitis.

Hypersensitivity pneumonitis

dynamic expiration

.

Subacute HP:air trapping

.

Biopsy proven HP

. expiratory scan

expiration

Hypersensitivitypneumonitis

air-trappingwith lung cyst

.

HRCT Diagnosis: Chronic HP, IPF, NSIPHRCT Diagnosis: Chronic HP, IPF, NSIPHRCT Diagnosis: Chronic HP, IPF, NSIPHRCT Diagnosis: Chronic HP, IPF, NSIP

• chronic HP: lobular areas of low attenuation, chronic HP: lobular areas of low attenuation, centrilobular ground-glass opacity nodules, centrilobular ground-glass opacity nodules, absence of lower lobe predominanceabsence of lower lobe predominance

• IPF: basal predominance of honeycombing, IPF: basal predominance of honeycombing, absence of subpleural sparing and nodulesabsence of subpleural sparing and nodules

• NSIP: subpleural sparing, absence of NSIP: subpleural sparing, absence of honeycombing and lobular low attenuationhoneycombing and lobular low attenuation

• confident diagnosis in 53%; correct in 94%confident diagnosis in 53%; correct in 94%

• chronic HP: lobular areas of low attenuation, chronic HP: lobular areas of low attenuation, centrilobular ground-glass opacity nodules, centrilobular ground-glass opacity nodules, absence of lower lobe predominanceabsence of lower lobe predominance

• IPF: basal predominance of honeycombing, IPF: basal predominance of honeycombing, absence of subpleural sparing and nodulesabsence of subpleural sparing and nodules

• NSIP: subpleural sparing, absence of NSIP: subpleural sparing, absence of honeycombing and lobular low attenuationhoneycombing and lobular low attenuation

• confident diagnosis in 53%; correct in 94%confident diagnosis in 53%; correct in 94%

Silva et al. Radiology 2008; 246:288288Silva et al. Radiology 2008; 246:288288

48 year old man with dyspnea

Hot tub lung

““Hot tub lung”Hot tub lung”““Hot tub lung”Hot tub lung”

• Immunocompetent subjectsImmunocompetent subjects

• symptoms within hours of hot tub usesymptoms within hours of hot tub use

• dyspnea, cough, hypoxemia, feverdyspnea, cough, hypoxemia, fever

• nonnecrotizing granulomas, often bronchiolocentricnonnecrotizing granulomas, often bronchiolocentric

• MAC (mycobactium avium) found on culture, less MAC (mycobactium avium) found on culture, less often on biopsy, and in the hot tubeoften on biopsy, and in the hot tube

• likely a hypersensitivity reactionlikely a hypersensitivity reaction

• resolution without antibiotic treatmentresolution without antibiotic treatment

• Immunocompetent subjectsImmunocompetent subjects

• symptoms within hours of hot tub usesymptoms within hours of hot tub use

• dyspnea, cough, hypoxemia, feverdyspnea, cough, hypoxemia, fever

• nonnecrotizing granulomas, often bronchiolocentricnonnecrotizing granulomas, often bronchiolocentric

• MAC (mycobactium avium) found on culture, less MAC (mycobactium avium) found on culture, less often on biopsy, and in the hot tubeoften on biopsy, and in the hot tube

• likely a hypersensitivity reactionlikely a hypersensitivity reaction

• resolution without antibiotic treatmentresolution without antibiotic treatment

Hypersensitivity Pneumonitis: chronic stageHypersensitivity Pneumonitis: chronic stageHypersensitivity Pneumonitis: chronic stageHypersensitivity Pneumonitis: chronic stage

• long term or repeated exposurelong term or repeated exposure

• irregular fibrosis: coarse scars, septal thickening, irregular fibrosis: coarse scars, septal thickening, traction bronchiectasis, honeycombing in sometraction bronchiectasis, honeycombing in some

• patchy, lacks a subpleural distribution in mostpatchy, lacks a subpleural distribution in most

• diffuse or predominantly involving mid lung zonesdiffuse or predominantly involving mid lung zones

• upper lobe involvement (atypical for IPF)upper lobe involvement (atypical for IPF)

• superimposed findings of subacute disease in some: superimposed findings of subacute disease in some: ground-glass opacity or nodulesground-glass opacity or nodules

• ““headcheese sign” with findings of fibrosisheadcheese sign” with findings of fibrosis

• long term or repeated exposurelong term or repeated exposure

• irregular fibrosis: coarse scars, septal thickening, irregular fibrosis: coarse scars, septal thickening, traction bronchiectasis, honeycombing in sometraction bronchiectasis, honeycombing in some

• patchy, lacks a subpleural distribution in mostpatchy, lacks a subpleural distribution in most

• diffuse or predominantly involving mid lung zonesdiffuse or predominantly involving mid lung zones

• upper lobe involvement (atypical for IPF)upper lobe involvement (atypical for IPF)

• superimposed findings of subacute disease in some: superimposed findings of subacute disease in some: ground-glass opacity or nodulesground-glass opacity or nodules

• ““headcheese sign” with findings of fibrosisheadcheese sign” with findings of fibrosis

Hypersensitivity Pneumonitis: progression

6 month follow-up.

.Chronic HP

.

Chronic HP

chronic HP:reticulation and

tractionbronchiectasis

.

chronic hypersensitivity pneumonitis

.

subacute HP:ground-glass opacity

chronic HP:reticulation and

tractionbronchiectasis

.

HRCT of CommonHRCT of CommonLung DiseasesLung Diseases

W. Richard WebbW. Richard Webb