CXR Interpretation

Question 1

What do each letter stand for when reading and CXR?
ABCDEFGH

Answer 1

-Assessment of the patient and detailed history
-Bones
-Cardiac silhouette and size
-Diaphragm
-Effusion and Equipment
-Fields of the lungs
-Great vessels and Gastric
-Helium

Question 2

ASSESSMENT-Three steps to check for good quality image on CXR

Answer 2

1. NO excess rotation of patient by checking that the medial ends of spinal processes are equality distanced from the vertebral body
2. Good inspiration should show 6-8 anterior ribs or 8-10 posterior ribs
3. Proper exposure by making sure you can see fine lung markings
   -Don’t forget the need to assess the patient and take detailed history

Question 3

What are four abnormal (bad) findings on CXR where air shouldn’t be ?

Answer 3

1. Pneumothorax
2. Pnemomediastinum
3. Pneumoperitoneum (air in the peritoneum, sign of perforation)
4. Subcutaneous emphysema

Question 4

BONES-Explain how you look at the bones on CXR

Answer 4

1. Look at both clavicles and shoulder joint
2. All 12 pair of ribs
3. Make sure you look at soft tissue outside of chest for swelling and masses or air

Question 5

CARDIAC SILHOUETTE AND SIZE-What are the three markers you look at for a cardiac silhouette?

Answer 5

1. Atrial appendage
2. Right atrium
3. Left ventricle

Question 6

What is normal measure of the heart on CXR?

Answer 6

-Less than 50% of diameter of the rib cage
-Transcardiac diameter should be less than half of transthoracic diameter

Question 7

DIAPHRAGMS-When does it look normal on CXR?

Answer 7

-Not too flat and fairly symmetric
-Right hemidiaphragm slightly higher than the L (room for heart)

Question 8

EQUIPMENT-Where should a correctly positioned ET tube be on CXR?

Answer 8

-Middle of the trachea
-The tip of ET tube should be > 2 cm from trachea bifurcation or carina
-Carina is typically located at T4-T5

Question 9

EFFUSION-What is pleural effusion?

Answer 9

-Pleural effusion is fluid that gets collected at the costophrenic angle
-Meniscus sign: loss of the sharp costophrenic angle on CXR

Question 10

FIELDS-What does a normal lung field look like on CXR?

Answer 10

-Symmetric, no haziness, no white spots or blotches
-Look for abnormalities: infiltrates or densities, air bronchogram, masses, lobar collapse, Kerley B lines

Question 11

GREAT VESSELS- What vessels does it include on CXR?

Answer 11

-SVC
-IVC
-Ascending aorta
-Aortic arch
-Pulmonary artery
-Descending aorta
-Deviation of heart blood vessels may indicate congenital or abnormality of the heart

Question 12

What are some indications of of ordering CXR?

Answer 12

-Shortness of breath
-Chest pain
-Persistent cough
-Hemoptysis
-Fever of unknown origin
-Hypoxemia
-Abnormal respiratory exam
-Chest trauma
-Suspicion of foreign body
-Confirm of device placement

Question 13

What are the three fissures and between what lung lobes?

Answer 13

-Horizontal fissure (major fissure): RUL and RML
-Oblique fissure (minor fissure): RML and RLL
-Oblique fissures (major fissure): LUL and LLL

Question 14

What are three views of CXR?

Answer 14

1. PA Posterior anterior view “routine”
2. AP Anteroposterior view portable
3. Lateral view, not done portable

Question 15

What is the adjacent structure of RUL?

Answer 15

Ascending aorta

Question 16

What is the adjacent structure of RLL?

Answer 16

Right diaphragm

Question 17

What is the adjacent structure of LUL?

Answer 17

Aortic knob

Question 18

What is the adjacent structure of LLL?

Answer 18

Left diaphragm and descending aorta

Question 19

When would you perform a lateral decubitus view ?

Answer 19

-To measure amount of pleural effusion, 1 ml of thickness of pleural fluid in the lateral decubitus is approx. 20 ml of pleural fluid

Question 20

What is hilum?

Answer 20

-A landmark where the bronchi, arteries, veins and nerves enter and exit the lung

Question 21

What is bilateral hilar lymphadenopathy ?

Answer 21

-Enlargements of the lymph nodes in the hilar regions of the lungs
-Can indicate infection, TB, cancer, sarcoidosis

Question 22

What are the clinical/physical and CXR findings of Asthma?

Answer 22

-Clinical/physical findings: wheezing, chest tightness, cough, shortness of breath, worsens at night, triggers to allergens or exercise
-CXR: generally normal in asthma but in severe asthma attack may show hyperinflation, increased lung markings and some atelectasis

Question 23

What does air bronchogram look on CXR?
What does it indicate?

Answer 23

-Air filled bronchi within affected lung area, these air filled bronchi appear as dark branching structures on CXR
-Indicates consolidation, pulmonary edema, non-obstructive atelectasis, pulmonary infarction

Question 24

What is the clinical/physical and CXR of findings of COPD?

Answer 24

-Clinical/physical findings: chronic cough, shortness of breath, sputum production, wheezing, barrel chest, history of smoking or exposure
-CXR: hyper inflated lungs, flat diaphragm, increased retrosternal space
-Pulmonary functions tests

Question 25

What is the clinical/physical and CXR findings of pneumonia and consolidation?

Answer 25

-Clinical/physical findings: sudden onset of fever, productive cough with purulent sputum, dyspnea, chest pain, crackles, increase tactile remits, dullness on percussion over affected areas
-CXR: change of density due to tissue more permeable inviting fluid there
-Consider aspiration pneumonia for older or stroke patients

Question 26

What is the clinical/physical and CXR findings of Atelectasis?

Answer 26

-Clinical/physical findings: gradual or sudden dyspnea, decrease breath sounds, may be associated with post operative or tumour or mucus plug, dullness to percussion over affected areas
-CXR: opacification or collapse of a portion of lung, affected lung may appear denser, mediastinal structure may shift in severe atelectasis, elevation of hemidiaphragm on contralateral side, silhouette sign with air bronchogram

Question 27

What is the clinical/physical and CXR findings of CHF/Pulmonary edema?

Answer 27

-Clinical/physical findings: orthopnea, paroxysmal nocturnal dyspnea, cough with pink frothy sputum, crackles, increased JVP, possible peripheral edema
-CXR: increased vascular markings, cephalization of vessels (engorged blood vessels in upper lung fields due to increase in pulmonary vessels), Kerley B lines (linear opacities, fluid in connective tissue of lung), alveolar edema leading to bat’s wing, increase cardiothoracic ratio

Question 28

What are three stages of heart failure?

Answer 28

1. Redistribution
2. Interstitial edema
3. Alveolar edema

Question 29

What is the clinical/physical and CXR findings of pneumothorax?

Answer 29

-Clinical/physical findings: sudden onset of sharp chest pain, dyspnea, decrease breath sound to one side, trauma or spontaneous, hyper resonance to percussion, possible tracheal deviation in tension pneumothorax
-CXR: dark area at the lung periphery, collapse lung, mediastinum shift towards the unaffected side

Question 30

What is the clinical/physical and CXR findings of subcutaneous emphysema?

Answer 30

-Clinical/physical findings: presence of air in soft tissue, palpable sensation of crepitus, clinical sign of pneumothorax, air leak, COPD
-CXR: dark area (air) outside of the lung