cxr interpretation

Interpretation of Interpretation of Chest RadiographsChest Radiographs

UNC Emergency MedicineUNC Emergency MedicineMedical Student Lecture SeriesMedical Student Lecture Series

ObjectivesObjectives

►The BasicsThe Basics Approach to interpretationApproach to interpretation AnatomyAnatomy Interstital diseaseInterstital disease Alveolar diseaseAlveolar disease

►Pattern RecognitionPattern Recognition►Practice!Practice!

InterpretationInterpretation

► Use a systematic approachUse a systematic approach Use or develop one you likeUse or develop one you like

► Use the same approach every time Use the same approach every time ►Describe what you seeDescribe what you see► Form a differential based on patient Form a differential based on patient

presentation and appearance of x-raypresentation and appearance of x-ray► If you find an abnormality, don’t stop thereIf you find an abnormality, don’t stop there

Finish your systematic readingFinish your systematic reading The second lesion is often missedThe second lesion is often missed

Systematic ApproachSystematic Approach

►ABCDEABCDE►AAirway (trachea)irway (trachea)

Midline v. deviated or rotated, FB in trachea, Midline v. deviated or rotated, FB in trachea, ET tube positionET tube position

►BBones (clavices, ribs, humeri, etc)ones (clavices, ribs, humeri, etc)►CCardiomediastinal silhoutteardiomediastinal silhoutte►DDiaphragms (and the costophrenic angles) iaphragms (and the costophrenic angles) ►EEverything Else (lung fields, soft tissues, verything Else (lung fields, soft tissues,

tubes, lines, wires, devices, etc)tubes, lines, wires, devices, etc)

Normal Chest RadiographNormal Chest Radiograph

Trachea

Right main stem bronchus

Left mainstem bronchus

Pulmonary artery

Pulmonary artery

Aortic knob

Left ventricle

Right atrium

Anatomy

Left hemidiaphragm

Right costophrenicangle Stomac

h

Upper lobes

Middle lobeLingula

Lower Lobes

Anatomy

Lower lobes

Upper lobes

Right middle lobe

Lingula

Common ViewsCommon Views

PA

AP

Left Lateral

Right anterior oblique

AP supine

Right lateral decubitus

Portable CXR

PA/Lateral CXR

These are from the Same Patient

Explain the difference…..

PA APAlways get a PA film to avoid cardiac magnificationExceptions: trauma, active cardiac chest pain, unstable, unable to cooperate with procedure

Silhouette SignSilhouette Sign

► Two substances of the Two substances of the same density, in direct same density, in direct contact, cannot be contact, cannot be differentiated from differentiated from each other on x-rayeach other on x-ray

► Common locationsCommon locations Lower lobes-diaphragmsLower lobes-diaphragms Right heart border – RMLRight heart border – RML Left heart border – Left heart border –

LingulaLingula Left diaphragm – Heart Left diaphragm – Heart

(on lateral view)(on lateral view)

Air Bronchogram SignAir Bronchogram Sign

► Visualization of air in Visualization of air in the intrapulmonary the intrapulmonary bronchibronchi

► Abnormal Abnormal ► Denotes a pulmonary Denotes a pulmonary

lesion/consolidation lesion/consolidation (excludes a pleural or (excludes a pleural or mediastinal lesion)mediastinal lesion)

► Seen in pneumonia, Seen in pneumonia, pulmonary edema or pulmonary edema or pulmonary infarct pulmonary infarct

An air bronchogram within the heart shadow suggests LLL consolidation

Silhouette sign

Interstitial Lung DiseaseInterstitial Lung Disease

► The vessels (lung The vessels (lung markings) appear markings) appear more prominentmore prominent

► Alveoli are still Alveoli are still aeratedaerated

►DDx: Pulmonary DDx: Pulmonary edema, edema, inflammation, inflammation, tumor, fibrosistumor, fibrosis

Alveolar DiseaseAlveolar Disease

► Vessels are less Vessels are less visible in the area of visible in the area of diseasedisease

► Lung is not aeratedLung is not aerated►May have air May have air

bronchograms or bronchograms or silhouette signsilhouette sign

►DDx: Bacterial DDx: Bacterial pneumonia, pneumonia, pulmonary edemapulmonary edema

Let’s PracticeLet’s Practice

►What type of filmWhat type of film►Describe what you seeDescribe what you see

Consolidation, infiltrate, nodular, diffuse, Consolidation, infiltrate, nodular, diffuse, streaky, opacificationstreaky, opacification

Look for Silhouette sign and air Look for Silhouette sign and air bronchogramsbronchograms

Is it an interstitial or alveolar pattern?Is it an interstitial or alveolar pattern? Other findings…Other findings…

►Give differential or diagnosisGive differential or diagnosis

75 yo F with hx of MI now presenting with SOB, hypoxia

Pulmonary edema

Opacification of right hemithorax, obscured left hemidiaphramDDx: Massive pleural effusion, right pneumonectomy

Multiple R sided rib fractures – flail chest

Opacification of left hemithorax, air-fluid level in left upper lobe, left clavicular fractureDiagnosis: Left empyema after trauma

Air-fluid (cavitary)lesion

Same patientLateral view

Air-fluid level

48 yo M with hx of PUD presenting with abdominal pain

pneumoperitoneum

67 yo smoker with one week of cough, sob, fevers

Left lower lobe pneumonia

““Spine Sign”Spine Sign”

http://images.google.com/imgres?imgurl=http://www.residentandstaff.com/content/RSP/2006/07/img/Case_pneum_1.jpg&imgrefurl=http://www.residentandstaff.com/issues/articles/2006-07_02.asp&h=572&w=580&sz=72&hl=en&start=23&um=1&tbnid=wBsgta58mO7XPM:&tbnh=132&tbnw=134&prev=/images%3Fq%3Dleft%2Blower%2Blobe%2Batelectasis%26start%3D21%26ndsp%3D21%26um%3D1%26hl%3Den%26sa%3DN

Dx: Subcutaneous air in neck and shoulder and pneumomediastinum (left heart border)

Lack of lung markings on right, collapsed lung

Dx: Complete rightpneumothorax

Collapsed lung

Is it a tension pneumothorax?

NO!NO!

►Tension PneumothoraxTension Pneumothorax Mediastinum is shifted to Mediastinum is shifted to oppositeopposite site of site of

pneumothoraxpneumothorax►Look at trachea and bronchiLook at trachea and bronchi►Look at heartLook at heart

Your patient is unstable or in distressYour patient is unstable or in distress►Absent breath soundsAbsent breath sounds►Respiratory difficulty, hypoxiaRespiratory difficulty, hypoxia►HypotensionHypotension►Trachea shiftedTrachea shifted

Deep sulcus signDeep sulcus sign

Thank You!Thank You!

Any Questions?Any Questions?