Thorax Part 3 Flashcards
what is seen in an alveolar pattern?
increased pulmonary opacity to the point where vessels cannot be distinguished
what is an alveolar pattern caused by?
decreased volume of air in the lungs
what causes decreased volume of air in the lungs?
lung is filled with crap: consolidation
lung is collapsed: atelectasis
what is atelectasis?
lung is collapsed
how does atelectasis occur?
recumbency
bronchial obstruction
what causes consolidation?
lung is filled with soft tissue opacity material: fluid or cells
how can you tell a radiograph is showing consolidation, not atelectasis?
consolidated lung will be normal size
no mediastinal shift with consolidation
how can you tell a radiograph is showing atelectasis, not consolidation?
atelectic lung will be smaller than normal
mediastinal shift with atelectasis
why is an atelectic lung smaller than normal?
alveoli are collapsed with nothing in them
where does pneumonia most often occur?
right middle lung lobe
ventral/cranioventral lung fields
where does cardiogenic edema usually occur?
starts perihilar, spreads everywhere
cats can have it anywhere
where does noncardiogenic edema usually occur?
caudodorsal lung fields
what are the four main possibilities when you see consolidation on chest radiographs?
pneumonia
cardiogenic edema
noncardiogenic edema
hemorrhage
when does a lobar margin sign occur?
when an opacified lung lobes is adjacent to a relatively normal lung lobe
when is a lobar margin sign often seen?
with lobar pneumonia
can be seen with masses
where does equine aspiration pneumonia most often occur?
accessory lung lobe
why do rule outs for interstitial and consolidating alveolar patterns overlap?
fluid enters/exits alveoli via interstitial space
interstitial and alveolar patterns can be thought of as a ____________________
continuum
what does an air bronchogram look like?
gas filled bronchial lumen in a completely opaque lung lobe, not bronchial wall is seen
is radiography sensitive for heart disease?
no
if heart disease is suspected, what should you do?
echocardiography
what should you distinguish between if the cardiac silhouette is large?
is it the pericardial sac or heart?
if the heart is enlarged, what should you narrow down?
which chambers/vessels are enlarged
what are concurrent abnormalities that would support heart disease with an enlarged cardiac silhouette?
ascites/pleural effusion
vascular changes
increased lung opacity
what is the vertebral heart score for?
qualitative measure of heart size
why was the vertebral heart score developed?
method of compensating for variation in the thoracic conformation of various breeds
how do you do a vertebral heart score?
measure the long axis of the heart from the carina to the apex
measure the short axis of the heart at thee widest point: usually ventral to caudal vena cava
starting at the cranial aspect of T4, measure the length of the axes in vertebrae and add them together
what is a normal dog’s vertebral heart score?
<10.5 (8.5-10.5)
labradors and boxers can go to 11
what is a normal cat’s vertebral heart score?
<8.1
7.2-8.1
what are some signs of right heart failure?
big right heart or generalized cardiomegaly
enlarged caudal vena cava
hepatomegaly: congestion
abdominal and/or pleural effusion
how can you tell the caudal vena cava is enlarged?
larger than aorta on multiple views or 1.5xaorta
how can you recognize a patent ductus arteriosus on the VD view?
overcirculated lungs
triple bump
left atrial enlargement
what are some signs of left heart failure?
big left heart or generalized cardiomegaly
pulmonary venous congestion
perihilar interstitial to alveolar pattern
what are some signs of left heart failure in cats?
edema may be anywhere
pleural effusion may be present
what might you see on radiographs of a cat with cardiomegaly?
accentuated caudal waist
atrial enlargement
