How to Read a CXRProforma Patient and CXR data: projection, posture

Adequacy: easily visible mid-thoracic IV spacesDegree of inspiration – diaphragm at levels of 8th -11th ribs posteriorly (or 5th - 6th ribs anteriorly)Degree of rotation – central spinous processes of thoracic vertebrae, equidistant from medial ends of claviclesAirway: Trachea: central; slight deviation to R as crosses aortic arch

Pushed away: large pleural effusion; large/tension pneumothorax; aortic aneurysm; mediastinal mass

Pulled towards: collapse; pul fibrosis; lobectomy, pneumonectomyBreathing: Lungs, Pleura (effusion, thickening, calcification) Lung outlines: look for pneumothorax, bullae, collapse, consolidation, effusions, masses, pleural changes; on lateral view lung lucency should increase towards diaphragm

Increased lucency towards diaphragm = COPD, pneumothorax Decreased lucency towards diaphragm = alveolar / interstitial fluid, effusion, Consolidation

Air bronchogram: tubular outline of an airway made visible by filling of the surrounding alveoli by fluid or inflammatory exudates

Caused by: lung consolidation; pulmonary edema; nonobstructive pulmonary atelectasis; severe interstitial disease; neoplasm; normal expiration

Circulation: Heart: 1/3 to R of thoracic spinous processes, CTR <50% R heart border = RA; Poor distinction = consolidation of RML L heart border = LV; Poor distinction = lingular consolidation

Increased CTR = AP film; LVD, CCF, pericardial effusion Pulmonary vessels

Diaphragm: R higher than L by 1-3cm Loss of outline = fluid, consolidation or collapse Flat diaphragm = COPD Gas under diaphragm = rupture of hollow viscus; Post-laparoscopy

Mediastinum: Hila: at T6-7 level; made of pul arteries and veins; L hilum 1-2cm higher and square shaped; R hilum V shaped

Width: <8cm superiorly on PA at carina (or >25% diameter of chest) Wide: AP view; unfolded aortic arch, thoracic AA, aortic rupture; mediastinal

lymphadenopathy; retrosternal thyroid, thymoma; paravertebral mass; oesophageal dilationBones: lesions or fracturesSoft tissues: don’t miss mastectomyTubes

Describing abnormalities: mediastinal / central / peripheral; UZ/MZ/LZ (according to lobe if lateral film available); number; size; shape; effects on adjacent structure

Views PA: Preferred view

Transverse fissure: from Jx of upper 1/3 and lower 2/3 lateral chest to R hilumLat: Helps delineate and localize masses, lesions or consolidation – esp if they are obscured by heart and diaphragm

L image, L lung: oblique fissure, as shown from T4 to 3cm post to where diaphragm and sternum meetR image, R lung: horizontal and oblique fissures, as shown

ÂP: Magnifies heart and mediastinumAssociated with rotational artefact

Expiratory: helpful for small pneumothroax / gas trapping with FB

Neonatal CXR

Neonatal RDS: miliary nodulation in lower zones / diffuse; ground glass; air bronchogramCF: bronchiectasis, peribronchial consolidationVaricella pneumonia: widespread nodules

Atelectasis Collapse or incomplete expansion of the lung or part of the lung segmental/subsegmental collapse linear/curvilinear/wedge-shaped increased density with apex at hilum; often assoc with volume loss; shift towards; may be compensatory hyperinflation of adjacent lobes, or hilar elevation / depression; air bronchogram can occurCompression: In lumen: mucus plug In wall: tumour, scarring, TB, post-radiation Extrinsic: LN’s, pleural effusion

Consolidation Describe: homogenicity, discreteness of margin, cavitation, effect on heart border Fluid (inflammatory, aspiration, pneumonia) Cells (bronchoalveolar Ca, sarcoidosis, lymphoma) Protein (alveolar proteinosis) Blood (pul haemorrhage – Goodpastures, high altitude, bleeding disorders, mitral stenosis)

Lobe collapse Silhouette sign:Silhouette of heart borders, a’ing and d’ing aorta, aortic knuckle and hemidiaphragms should be clearly visible; obliteration of any of these borders suggests pathologyNote, pathology in posterior pleural cavity and lower mediastinum cause overlap but not obliteration of heart borderLook for: loss of vol of lobe, loss of lucency, displacement of fissures, wider spacing of vascular shadows of rest of lung

LUL collapse Loss of aortic knuckle and upper L heart border Retrosternal band of opacity with well defined oblique fissure on lateral

Heart 60-65% chest widthBronchial branching may give sense of air bronchogramsThymus (involution occurs age 6yrs; not usually seen after 2yrs; is anterior on lateral; L lobe larger than R; extends as low as 4th costal cartilage; lung markings visible through it; does not displace trachea)

LLL collapse Loss of L hemidiaphragm and descending aorta Triangular opacity between heart shadow and spine on lateral

RUL collapse Loss of ascending aorta and upper R heart border Opacity at RUZ apex of mediastinal border Deviation of trachea to R

RML collapse:Loss of R heart border (vague R pericardiac haze)On lateral, 2 fissures start to approximate (depression of horizontal) causing wedge opacity pointing to hilum

RLL collapse:R heart border unaffected Loss of R hemidiagphragmTriangular density posteromedially

Lingular consolidation: loss of L heart border

Pneumonia Airspace opacity / lobar consolidation / interstitial opacitiesNormal/incr volume (volume loss NOT seen); no shift; not centred at hilum; can cause air bronchogramsLobar: strep pneumoniae; uniform opacity confined to one lobe; air bronchograms seen; may be ill defined if not adjacent to one of the fissures; may be small assoc pleural effusionLobular: staph; multifocal, patchyLower zones: legionellaUpper zones: klebsiellaRound pneumonia: C Burnetti, S pneumoniae, L pneumophilia, S aureusBronchial: ill defined areas of patchy opacity (eg. Post-op, aspiration)Diffuse: community acquired, nosocomial, ImmunocompromisedMiliary pattern / intersitital: TB, varicella pneumonia; air bronchogram not seen

Interstitial lung disease

SHITFACED

SarcoidosisHistiocytosisIdiopathicTumour: mets, lymphangitisFailureAutoimmune: SLE, RA, scleroderma, polymyositis; granulomatosis; hypersensitivity pneumonitisCollagen vascular diseaseEnvironmental: Asbestos, silicosis, farmer’s lung, coalDrugs: Methotrexate, amiodaroneOther: atypical pneumonia, fungal, viral; radiation pneumonitis

Lung asbcess

Cavitating lung lesions

CAVITY

Cancer: more likely if anterior; esp if SCC; advanced HodgkinsAutoimmune: granulomatosis, sarcoidosis, Wegener’s RA, progressive massive fibrosisVascular: septic emboli and pul infarctInfectious: 2Y TB, abscess, cocci, infected bullae / cystsTrauma: traumatic cystYoung: bronchogenic cyst, laryngotracheal papillomatosis

TB 1Y small area consolidation in lower UL or upper LL, adenopathy, pleural effusionPost-1Y TB hilar LN calcification, small calcified nodule (Ghon focus)2Y cavitating lung lesions with surrounding fibrosis (esp in UL with elevation of hila and incr lucency of remaining lung fields), focal patchy airspace disease, no hilar lymphadenopathyMiliary 1-2mm diffuse nodules

Pleural effusion

Erect: blunting CP angle (lateral on PA, posterior on lat); >100ml to see on PA, 75ml to see on Lat; upper margin should be concave – if flat, also pneumothorax; can cause tracheal shift (unlike consolidation)Supine: graded haze, denser at base; vascular shadows can be seen through effusion; if large, fluid cap over apex; do lateral decubitusCauses: CCF, infection, trauma, PE, tumour, autoimmune disease, renal failure; if large, more likely CaR sided – Meig’s syndrome (ovarian Ca)L sided – pancreatitis, chylothorax, CCF

ARDS

PE Westermark’s sign (oligaemia in area of involvement); Hampton’s humpIncreased size of hilum (thrombus impaction); Atelectasis with elevation of hemidiaphragm and linear densities; Pleural effusion; Consolidation

Bacterial: staph aureus, Klebsiella, anaerobes, G-ives, TB, aspiration pneumonia; bronchial obstruction; if multiple, think of R sided bacterial endocarditisFungal (eg. Aspergillosis, cryptococcal)If assoc with pleural effusion: staph aureus, anaerobes, G-ives, TBImmuncompetent: anaerobes more commonImmunocompromised = staphs2-10% mortality if community acquired, 60% if hospital acquired; shows AF level (present if communicates with bronchioles; dense area of consolidation if doesn’t and will need CT to diagnose)

Bilat pul infiltrates with air bronchograms occuring after 12hrs clearing after 5/7 fibrosis with reticular pattern after 7/7

CCF

Pulmonary nodules

Benign: unchanged for two years is almost certainly benign; completely calcified or central or stippled Calcium; solitarySuspicious: nodules with irregular calcifications or those that are off center; Multiple nodules; 1Y tumours don’t calcify, may have satellite lesions; 1Y poorly defined; may show umbilication; may have linear strands connecting to hilum (lymphatics), usually double in size in 1-6/12

Solitary pul nodule: 30-40% malignant; <3cmAdenoma: usually central, hilar, smooth and round; 1% of all neoplasmsNeoplasia: assoc with collapse, hilar enlargement, elevated hemidiaphragm, bony destruction, lines lymphatic infiltration with connects to hilum Mets: usually more sharply defined than 1Y; multiple; colon, breast, renal cell, testicular, TCC, melanoma If diffuse rather than nodular: prostate, stomach, pancreas, lymphoma, thyroid If calcify: breast, osteogenic Ca, thyroid, ovarian, mucinous adenoCa Adenocarcinoma (35-50%): peripheral SCC (30%): central, hilar involvement, cavitation common Small cell (15-20%): central; hilar and mediastinal masses Large cell (10-15%): peripheral; large; cavitation present Bronchoalveolar (3%): peripheral; rounded; air bronchograms Carcinoid (<1%): well-defined endobronchial lesion Other: lymphomaInfection (round pneumonia (esp children and young adults; C Burnetti, S pneumoniae, L pneumophilia, S aureus); atelectasis; abscess; miliary TB (cavitation, calcification), varicella pneumonia, histoplasmosis, aspergilloma, fungal, Nocardia infection, hydatid diseaseVascular: AVM, haemartoma (smooth 2-4cm lobulated with popcorn calcification), PE, infarctAutoimmune: more likely multiple; granuloma, RA, Wegener’s, fibrotic lung disease (eg. Silicosis)Other: pleural plaques, bronchial atresia, sequestration, chrondroma

Emphysema Hyperinflation with flattening of diaphragms; Increased retrosternal space; Bullae (have no vessels and are not perfused); Enlargements of PA / RV; reduced vascular markings esp in periphery; long thin heart, clockwise rotation of heart; kyphosis and sternal bowing

Pulmonary fibrosis

Upper lobe diversion (upper lobe vessels usually smaller than lower), basilar and hilar infiltrates, widening of vascular pedicle, peribronchial cuffing, Kerly B lines (also found in silicosis, lymphagnitis carcinomatosis, sarcoidosis), CTR >0.5 (>0.7 in infants), pleural effusions; XR more sens than examination

SETCARP

BADRASH

BIGHIPS

Upper zone (SETCARP): Silicosis (multiple nodules, hilar LN with egg shell calcification) Sarcoidosis (mediastinal > paratracheal nodes, calcification rare, miliary nodulation and large nodules) Eosinophilic pneumonia TB Coal miner’s pneumoconiosis, CF Aspergillosis, ank spond Radiation therapy PCP, pneumoconiosis

Lower zone (BADRASH): Bronchiectasis Aspiration Drugs RA Asbestosis (shaggy heart from adhesions, pleural thickening and calcification, mesothelioma) Scleroderma Hamman Rich syndrome, histiocytosis

Honeycomb (BIGHIPS): Bleomycin Idiopathic Granulomas Histiocytosis Interstitial pneumonia Pneumoconiosis SarcoidDrugs (methotrexate, nitrofurantoin, hydralazine, amiodarone), paraquat, smoke inhalation, ARDS

Pneumothorax

Etched diaphragm (1) / mediastinum (2) : contrasted with air in pleural space; diaphragm may be flattened

Deep sulcus sign (3): abnormally prominent/deep lateral CP angleVisible visceral pleura (4), Mediastinal / tracheal shift, Uneven lung density, Absent lung markings, subC emphysemaDD: scapula, skin fold, bullae, companion shadow, post-pleurectomy, drain tube track line

Pneumo-mediastinum

Streaky lucencies over mediastinum extending into neckElevation of parietal pleura along mediastinal bordersCauses: Asthma, whooping cough, surgery, traumatic tracheobronchial rupture, abrupt changes in intrathoracic pressure (eg. coughing, vomiting), ruptured oesophagus, barotrauma, cocaine

Hydro-pneumothorax

Mediastinal masses

Pleural masses

MALLETS

Are broad based to chest wall, usually 2YMesotheliomaAdenocarcinoma, asbestosisLymphoma, LeukaemiaEmpyema (or loculated pleural effusion)ThymomaSplenosis

Extra-pleural masses

Rib tumour; Rib infectionNeurofibroma / schwannoma; Lipoma

Trauma, thoracentesis, surgery, ruptured oesophagus, empyema

Ant: between heart and sternum Upper: LN’s, thyroid mass Middle: LN, ascending aortic aneurysm, thymus, teratoma, lipoma Lower: fat pad, pericardial cyst, herniaMiddle: LN; Aortic aneurysm; pul art; Bronchogenic cystPost: between heart and spine Upper: pharygneal pouch, neurogenic tumour Middle: hiatus hernia, dlated oesophagus, descending aoric an. Lower: hernia, neurogenic tumour, TB of spine, Hodgkins

Pericardial effusion

Hilar lymphadenopathy

Inflammation (sarcoidosis, silicosis)Neoplasm (lymphoma, metastases, bronchogenic carcinoma)Infection (TB, histoplasmosis, infectious mononucleosis)May be vascular disease (eg, pul HTN – will have more smooth border)

Notes from: See p 490 TinTin for non infectious causes of pul infiltrates

Globular enlarged heart shadow; 400-500ml fluid present to be seen on CXR (200ml for pleural effusion)Fat pad sign: soft tissue stripe >2mm between epicardial fat (blue arrows) and ant mediastinal fat (red arrows) seen anterior to heart on lateral view