Thorax/lung radiographs Flashcards
what are the indications for thoracic radiography?
metastasis exam
respiratory dysfunction
cardiac disease
esophageal or issues with deglutition
post-surgical complications
establish baseline/normalcy
thorax radiographs tend to have _____ inherent contrast. because of this, we have to use _____ kVp and _____ mAs to ________ latitude.
a lot of
high kVp, low mAs, raise latitude
if you can, take radiographs during ______ (phase of ventilation)
inspiration
ideally, _____ (#) views is best for thoracic radiographs. Which views are these? if you had to do only the bare minimum, what would you do? (small animal)
3
both laterals and VD
bare min: one lateral and VD or DV (2 views)
how do you position the animal for a thoracic radiograph? (small animal)
thoracic limbs pulled forward, rib heads/sternebrae/vertebrae superimposed, limbs out of way, avoid patient rotation, hemithorax’s symmetrical
Lateral views are better for certain things with thoracic radiographs. Tell me about them
R lateral: cardiac assessment and L pulmonary lobes
L lateral: R pulmonary lobes (asp. pneumonia)
what structures can you evaluate on a thoracic radiograph?
resp: lungs/trachea
CV: heart + vessels
pleural space
mediastinum: lymph nodes, esophagus, trachea, vessels
extra thoracic structures: ribs, limb, diaphragm, SQ
VD vs DV are better for different things in thoracic radiography. what are they? which is more common?
VD more common
- cranial mediastinum, pleural effusion easier to evaluate
- allows better inflation
DV
- evaluation of caudal lung lobes (met check)
- less resp restriction
- pulmonary edema
What is the vertebral heart score? What is the mean?
used to evaluate cardiac size, compares heart to mid-thoracic vertebrae (ID enlargement, monitoring change)
place length of both short and long axes along vertebrae, starting at T4 and going caudally. number of vertebrae along measurement (add together short and long axes) –> VHS
mean: 9.7 ± 0.5 (dogs), <8 (cats)
short axis: middle 3rd of heart (incl. R atrium & L chambers)
long axis: tracheal carina to cardiac apex (incl. L atrium + ventricle)
how do LA differ from SA in terms of thoracic radiographs?
only lateral projections, done standing, named by surface adjacent to plate (like other lateral views), may require 4-5 images to acquire entire thorax
caudal lobar vessels best seen in _____. cranial lobar vessels best seen in ____ - non-dependent lung best
DV
lateral
what are the 3 main pulmonary patterns? how are these defined?
alveolar
bronchial
interstitial (structured/nodular and unstructured)
defined by the primary location of parenchymal disease
alveolar patterns arise because … why?
alveoli are no longer air filled
air is replaced by ST opacity/fluid, or collapsed
occurring within alveoli ± extension into bronchi
in an alveolar pattern, what could be filling the alveoli?
consolidation - air replaced by fluid/ST (edema, blood, purulent material, neoplasia)
atelectasis - air absent but not replaced, tissue vol is lost = collapse
how is an alveolar pattern defined?
air bronchogram
effacement
lobar sign
soft tissue/fluid opaque lung when extensive
not all components required!