Chest Radiography Interpretation: Reading Chest Films

Chest Radiography Chest Radiography Interpretation: Interpretation: Reading Chest FilmsReading Chest Films

Lisa Chen , M.D.Assistant Clinical Professor

Pulmonary and Critical Care DivisionDepartment of Medicine

San Francisco General Hospital

Michael Gotway, MDAssociate Clinical Professor, RadiologyUniversity of California, San Francisco

Approach to the CXR:Technical Aspects

Approach to the CXR:Approach to the CXR:Technical AspectsTechnical Aspects

Inspiratory effort 9-10 posterior ribs

Penetration thoracic intervertebral disc space just visible

Positioning/rotationmedial clavicle heads equidistant to spinous

process

Inspiratory effort 99--10 posterior ribs10 posterior ribs

Penetration thoracic intervertebral disc space just visiblethoracic intervertebral disc space just visible

Positioning/rotation medial clavicle heads equidistant to spinous medial clavicle heads equidistant to spinous

processprocess

Low Lung VolumesLow Lung Volumes

Over ExposureOver Exposure Proper ExposureProper Exposure

101010

What to EvaluateWhat to EvaluateWhat to Evaluate

Lungs Pleural surfaces Cardiomediastinal contours Bones and soft tissues Abdomen

Lungs Pleural surfaces Cardiomediastinal contours Bones and soft tissues Abdomen

Where to LookWhere to LookWhere to Look

Apices Retrocardiac areas (left and right) Below diaphragm

Apices Retrocardiac areas (left and right) Below diaphragm

Apical TBApical TB

Left Left RetrocardiacRetrocardiac OpacityOpacity

Normal Anatomy: Frontal CXRNormal Anatomy: Frontal CXRNormal Anatomy: Frontal CXR

Heart Aorta Pulmonary arteries Airways Diaphragm/costophrenic sulci Junction lines

Heart Aorta Pulmonary arteries Airways Diaphragm/costophrenic sulci Junction lines

Normal Anatomy: LateralNormal Anatomy: LateralNormal Anatomy: Lateral

Heart Aorta Pulmonary arteries Airways Spine

Heart Aorta Pulmonary arteries Airways Spine

AAAA

RVRV

LVLV

Chest Radiography: Basic Principles

Chest Radiography: Chest Radiography: Basic PrinciplesBasic Principles

X-ray photon fates: completely absorbed in patient transmitted through patient; strike film scattered within patient; strike film

X-ray absorption depends on: beam energy (constant) tissue density

X-ray photon fates: completely absorbed in patientcompletely absorbed in patient transmitted through patient; strike filmtransmitted through patient; strike film scattered within patient; strike filmscattered within patient; strike film

X-ray absorption depends on: beam energy (constant)beam energy (constant) tissue densitytissue density

Maximum xMaximum x--rayrayTransmissionTransmission

(least dense tissue)(least dense tissue)

Maximum xMaximum xray ray AbsorptionAbsorption

(densest tissue)(densest tissue)

BlackestBlackest

airair

fatfat

soft tissuesoft tissue

calciumcalcium

bonebone

xx--ray contrastray contrast

metalmetal

WhitestWhitest

All cardiothoracic pathology and normal anatomy is visualized (or not) by 7 different densities

How is this accomplished? differential x-ray absorption

All cardiothoracic pathology and normal anatomy is visualized (or not) by 7 different densities

How is this accomplished? differential xdifferential x--ray absorptionray absorption

Chest Radiography: Basic Principles

Chest Radiography: Chest Radiography: Basic PrinciplesBasic Principles

A structure is rendered visible on a radiograph by the juxtaposition of two different densities

A structure is rendered visible on a radiograph by the juxtaposition of two different densities

Differential X-Ray AbsorptionDifferential XDifferential X--Ray AbsorptionRay Absorption

Silhouette SignSilhouette SignSilhouette Sign

Loss of the expected interface normally created by juxtaposition of two structures of different density

No boundary can be seen between two structures of similar density

Loss of the expected interface normally created by juxtaposition of two structures of different density

No boundary can be seen between two structures of similar density

Right Lower Lobe PneumoniaRight Lower Lobe Pneumonia

Differential X-Ray AbsorptionDifferential XDifferential X--Ray AbsorptionRay Absorption

The absence of a normal interface may indicate disease;

The presence of an unexpected interface may also indicate disease

The presence of interfaces can be used to localize abnormalities

The absence of a normal interface may indicate disease;

The presence of an unexpected interface may also indicate disease

The presence of interfaces can be used to localize abnormalities

Chest Radiographic Patterns of DiseaseChest Radiographic Chest Radiographic Patterns of DiseasePatterns of Disease

Air space opacity Interstitial opacity Nodules and masses Lymphadenopathy Cysts and cavities Lung volumes Pleural diseases

Air space opacity Interstitial opacity Nodules and masses Lymphadenopathy Cysts and cavities Lung volumes Pleural diseases

Cardiomediastinal contour abnormalities Bone and soft tissue abnormalities Below the diaphragm: abdominal and

retroperitoneal disease

Cardiomediastinal contour abnormalities Bone and soft tissue abnormalities Below the diaphragm: abdominal and

retroperitoneal disease

Chest Radiographic Patterns of DiseaseChest Radiographic Chest Radiographic Patterns of DiseasePatterns of Disease

Air Space OpacityAir Space OpacityAir Space Opacity

Components: air bronchogram: air-filled bronchus

surrounded by airless lung confluent opacity extending to pleural

surfaces segmental distribution

Components: air air bronchogrambronchogram: air: air--filled bronchus filled bronchus

surrounded by airless lungsurrounded by airless lung confluent opacity extending to pleural confluent opacity extending to pleural

surfacessurfaces segmental distributionsegmental distribution

Air Space Opacity: DDXAir Space Opacity: DDXAir Space Opacity: DDX

Blood (hemorrhage) Pus (pneumonia) Water (edema) hydrostatic or non-cardiogenic

Cells (tumor) Protein/fat: alveolar proteinosis and

lipoid pneumonia

Blood (hemorrhage) Pus (pneumonia) Water (edema) hydrostatic or nonhydrostatic or non--cardiogeniccardiogenic

Cells (tumor) Protein/fat: alveolar proteinosis and

lipoid pneumonia

LUL PneumoniaLUL Pneumonia

Interstitial OpacityInterstitial OpacityInterstitial Opacity

Hallmarks: small, well-defined nodules lines interlobular septal thickening fibrosis

reticulation

Hallmarks: small, wellsmall, well--defined nodulesdefined nodules lines lines interlobular septal thickeninginterlobular septal thickening fibrosisfibrosis

reticulationreticulation

Interstitial Opacity: Small NodulesInterstitial Opacity: Small Nodules

Interstitial Opacity: Interstitial Opacity: LinesLines

Interstitial Opacity: Lines & ReticulationInterstitial Opacity: Lines & Reticulation

Interstitial Opacity: DDXInterstitial Opacity: DDXInterstitial Opacity: DDX

Idiopathic interstitial pneumonias Infections (TB, viruses) Edema Hemorrhage Noninfectious inflammatory lesions sarcoidosis

Tumor

Idiopathic interstitial pneumonias Infections (TB, viruses) Edema Hemorrhage Noninfectious inflammatory lesions sarcoidosissarcoidosis

Tumor

Nodules and MassesNodules and MassesNodules and Masses

Nodule: any pulmonary lesion represented in a radiograph by a sharply defined, discrete, nearly circular opacity 2-30 mm in diameter

Mass: larger than 3 cm

Nodule: any pulmonary lesion represented in a radiograph by a sharply defined, discrete, nearly circular opacity 2-30 mm in diameter

Mass: larger than 3 cm

Nodules and MassesNodules and MassesNodules and Masses

Qualifiers: single or multiple size border definition presence or absence of calcification location

Qualifiers: single or multiplesingle or multiple sizesize border definitionborder definition presence or absence of calcificationpresence or absence of calcification locationlocation

MassMass

CalcificationCalcification

WellWell--DefinedDefined

IllIll--DefinedDefined

LymphadenopathyLymphadenopathyLymphadenopathy

Non-specific presentations:mediastinal widening hilar prominence

Specific patterns: particular station enlargement

Non-specific presentations: mediastinal wideningmediastinal widening hilar prominencehilar prominence

Specific patterns: particular station enlargementparticular station enlargement

Right Paratracheal Right Paratracheal LymphadenopathyLymphadenopathy

Right Hilar LANRight Hilar LAN

Right Hilar LANRight Hilar LAN

Left Hilar LANLeft Hilar LAN

Subcarinal LANSubcarinal LAN

Subcarinal LANSubcarinal LAN

*

AP Window LANAP Window LAN

Cysts & CavitiesCysts & CavitiesCysts & Cavities

Cyst: abnormal pulmonary parenchymal space, not containing lung but filled with air and/or fluid, congenital or acquired, with a wall thickness greater than 1 mm epithelial lining often present

Cyst: abnormal pulmonary parenchymal space, not containing lung but filled with air and/or fluid, congenital or acquired, with a wall thickness greater than 1 mm epithelial lining often presentepithelial lining often present

Cysts & CavitiesCysts & CavitiesCysts & Cavities

Cavity: abnormal pulmonary parenchymal space, not containing lung but filled with air and/or fluid, caused by tissue necrosis, with a definitive wall greater than 1 mm in thickness and comprised of inflammatory and/or neoplastic elements

Cavity: abnormal pulmonary parenchymal space, not containing lung but filled with air and/or fluid, caused by tissue necrosis, with a definitive wall greater than 1 mm in thickness and comprised of inflammatory and/or neoplastic elements

Cysts & CavitiesCysts & CavitiesCysts & Cavities

Characterize: wall thickness at thickest portion inner lining presence/absence of air/fluid level number and location

Characterize: wall thickness at thickest portionwall thickness at thickest portion inner lininginner lining presence/absence of air/fluid levelpresence/absence of air/fluid level number and locationnumber and location

Benign Lung Cyst : Benign Lung Cyst : PCPPCP PneumatocelePneumatocele Uniform wall thicknessUniform wall thickness 1 mm1 mm Smooth inner liningSmooth inner lining

Benign Cavities :Benign Cavities :CryptococcusCryptococcus

max wall thickness max wall thickness 4 mm4 mm minimally irregular inner liningminimally irregular inner lining

Indeterminate CavitiesIndeterminate Cavities

max wall thickness max wall thickness 55--15 mm15 mm mildly irregular inner liningmildly irregular inner lining

Malignant Cavities: Squamous Cell CaMalignant Cavities: Squamous Cell Ca max wall thickness max wall thickness 16 mm16 mm Irregular inner liningIrregular inner lining

Pleural Disease: Basic PatternsPleural Disease: Basic PatternsPleural Disease: Basic Patterns

Effusion angle blunting to massivemobility

Thickening distortion, no mobility

Mass Air Calcification

Effusion angle blunting to massiveangle blunting to massive mobilitymobility

Thickening distortion, no mobilitydistortion, no mobility

Mass Air Calcification

Pleural EffusionPleural Effusion

Pleural EffusionPleural Effusion

Subpulmonic EffusionSubpulmonic Effusion

Pleural CalcificationPleural Calcification

Chest Radiography Interpretation: Reading Chest FilmsApproach to the CXR:Technical AspectsWhat to EvaluateWhere to LookNormal Anatomy: Frontal CXRNormal Anatomy: LateralChest Radiography: Basic PrinciplesChest Radiography: Basic PrinciplesDifferential X-Ray AbsorptionSilhouette SignDifferential X-Ray AbsorptionChest Radiographic Patterns of DiseaseChest Radiographic Patterns of DiseaseAir Space OpacityAir Space Opacity: DDXInterstitial OpacityInterstitial Opacity: DDXNodules and MassesNodules and MassesLymphadenopathyCysts & CavitiesCysts & CavitiesCysts & CavitiesPleural Disease: Basic Patterns