CXR

• types

  PA: ideal type (左邊等於左邊)

  • hand behind head
  • scapular not visible

  AP: for patient unable to stand

  quality criteria RIP

  rotation: rib alignment (side closer to x ray experience greater attenuation, lung appear whiter)

  degree of inspiration: able to see 10th posterior rib, 6th anterior shd be above diaphragm (too many=hyperinflation/too few=poor inspiration)

  penetration: spinous process above heart shd be visible/ gap between vertebral bodies should be visible in heart shadow
• airway: midline shift

  bone: look for fracture

  cardiac silhouette: heart size shd be less than radius of chest

  diaphragm: shd be rounded

  edges: outline heart and mediastinum

  fields: assess lung volum, opacotoes, nodules

  gas: evaluate presence of gastric bubble below left hemidiaphragm indicate pmeumothorax

  A) trachea

  B) mediastinum

  C) hilum

  D) heart

  E) diaphragm

  F) lung

  G) bone

  H) soft tissue

  
• white lung field:

  left upper lung collapse:

  trachea deviate to left/ pneumonia/ atelectasis 肺不張/ elevated left hilum

  left lower lobe collapse:

  area increased density behind heart= consolidation

  right upper lobe collapse:

  trachea deviate to right/ horizontal fissure and hilum move up

  right middle lobe collapse:

  horizontal fissure displace down/ loss of R heart border maybe blocked by collapse lung tissue
• consolidation vs collapse

  • consolidation has unclear boundary, collapse has clear
  • consolidation has air bronchograms(air filled bronchi surrounded), collapse doesnt have
  • consolidation wont compress rib, collapse will
  • consolidation wont cause mediastinum shift, collapse will
• pulmonary oedema

  • cardiac hypertrophy : heart enlarge due to fluid accumulation, increased workload
  • bat wing appearance
  • hilum blurred: fluid accumulation, increased vascular marking
  • pleural effusion: fluid usually accumulate to one side instead of medial
  • kerley b line: show fluid build up in interlobular septa
• black lung field

  • hyperinflation: low horizontal disphragm
  • pneumothorax: unilateral black lung/ sharp edge/ lack of lung marking(tension pneumothorax: trauma, air trapped in pleura, cause mediastinum shift/ spontaneous pneumothorax: air sac rupture, lung collapse)
  • bullae emphysema: alveoli lose easticity and damaged, combined tgt into large air sac bullae, which take up space and push against surrounding structure
• mediastinum

  • thyroid
  • aorta
  • oesophagus
• .

  A) cardiophrenic angle

  B) costophrenic angle

  
• • trachea slightly displace to right
  • lung marking 1-2 cm away from rib shd be seen
  • right diphragm higher than left
  • left hilum 2.5 cm higher than right
  • right heart 1/3 , left heart 2/3