Diagnostic Imaging (1-6) Flashcards
what phase of respiration do you want to take a thoracic radiograph during
inspiratory
do you want high or low contrast in a thoracic radiograph?
low contrast image
what kVp and mAs is needed for a low contrast image of the thorax
high kVp & low mAs
why do you need to take 3-views of the thorax?
and what are these 3 views
recumbent lung collapses under weight of the heart;
so take L lat. recumbency, R lat. recumbency, and VD/DV
what are the 5 Röntgen signs that every organ should be assessed for on radiography
- size
- shape
- opacity
- location
- number/presence
do cats have a clavicle?
yes, prominent
name 4 changes in the lungs that may be seen in an old dog
“old dog lungs”
- pleural thickening
- incr. bronchial mineralization
- incr. foci of heterotropic bone
- incr. lung opacity w/ interstitial pattern & bronchial mineralisation
name the order of the thorax anatomic approach to interpreting a radiograph
- non-thoracic soft tissue: neck and abdomen
- skeleton
- heart & vessels
- pleural space
- lungs (most difficult, do last)
where the pulmonary veins in relation to the bronchus
ventral & central
where are the pulmonary arteries in relation to the bronchus
dorsal & peripheral
on a lateral view, the cranial pulmonary vessel diameter should be smaller than what rib width?
< 4th proximal rib width
on a VD/DV radiographic view, the caudal pulmonary vessel diameters should be smaller than what rib width?
< 9th rib width at cross point
name 3 signs of hypovolaemia that can be seen on a thoracic radiograph
- small pulmonary arteries and veins
- small cardiac sillhouette
- hyperlucent lung fields, normal size
name 3 factors (not diseases) that might cause lungs to have increased opacity on radiography
- technical
- underinflation
- obese patient
name 2 factors (not diseases) that may cause lungs to have decreased opacity on a radiograph
- technical
- manual hyperinflation
name 3 reasons that lungs may have hyperinflation and decreased opacity on a radiograph
- stress
- emphysema
- reduced vascular blood supply
name 2 reasons lungs might be hypovascular and have decr. opacity on a radiograph
- shock, dehydration
- Addison’s disease
what 5 patterns can diffusely increased lung opacity have?
- alveolar
- bronchial
- vascular
- nodular
- unstructured interstitial
name the pattern of diffusely incr. lung opacity
white and fluffy
alveolar
name the pattern of diffusely incr. lung opacity
rings & tramlines
bronchial
name the pattern of diffusely incr. lung opacity
too mant too big vessels
vascular
name the pattern of diffusely incr. lung opacity
soft tissue nodules
nodular
name the pattern of diffusely incr. lung opacity
moderately incr. diffuse opacity;
vessels still visible
unstructured interstitial
name 4 causes of an alveolar lung pattern (soft tissue opaque lung)
- oedema
- inflammation/infection
- haemorrhage
- neoplasia
name 2 causes of ventral alveolar lung pattern
- pneumonia
- aspiration pneumonia
name a cause perihilar alveolar lung pattern
canine cardiogenic pulmonary oedema
name 2 causes of caudodorsal alveolar lung pattern
- non-cardiogenic oedema
- inhaled foreign body pneumonia
name 2 causes of diffuse alveolar lung pattern
- haemorrhage
- viral pneumonia
name 3 Roentgen signs of alveolar lung pattern
- soft tissue opacity w/o distinguishable vessels
- airbronchograms
- border effacement
name 2 features of bronchial lung pattern
- bronchial thickening, bronchiectasis
- bronchial mineralization
name 5 things that may cause interstitial lung pattern on radiograph
- underexposure
- expiration
- interstitial oedema
- inflammation
- cellular infiltrate
name the 2 possible types of expansion with chest wall masses
- intrathoracic expansion
- extrathoracic expansion
name 2 possible congenital malformations of the ribs
- pectus excavatum
- pectus carinatum
name 3 possible types of fractures of the ribs
- acute with sharp margins
- chronic (often malunion or non-union)
- flail chest
name 2 common incidental findings of the ribs
(not a clinical concern)
- mineralized rib cartilage
- canine osteochondromas
what recumbency is the patient in?
Y-shaped dorsal hemidiaphragms;
Caudal Vena Cava (CVC) continues to more caudal right hemidiaphragm
left lateral recumbency
what recumbency is the patient in?
parallel dorsal hemidiaphragms;
Caudal Vena Cava (CVC) ends at more cranial right hemidiaphragm
right lateral recumbency
what does cranial diaphragmatic displacement usually indicate
space-occupying lesion in the abdomen
what does caudal diaphragmatic displacement usually indicate
space-occupying lesion in the thorax
what 3 things can cause lung-chest wall separation (abnormalities in pleural space)
- fluid
- soft tissue mass
- gas
name 3 radiographic signs of pleural effusion
- fissure lines
- cardiac border effacement
- separation lung - boundaries (lung lobe retraction)
what might scalloping (undulating lung margin) on a thoracic radiograph indicate
- pyothorax
- chylothorax
- chronic hydrothorax
this is a localized pleural soft tissue opacity ;
mole hill-like medial deviation of pulmonary margins ;
differentiates thoracic wall from lung mass
extrapleural sign
what 5 structures are normally visible on radiograph in the mediastinum
- trachea with carina
- caudal vena cava
- aorta
- parts of oesophagus
- juvenile thymus
name 4 possible pathologies of the mediastinum
- pneumomediastinum
- shift
- widening
- masses
what is the cardiac sillhouette comprised of
- heart
- pericardium
what 4 things should you assess of the cardiac silhouette
- size
- shape
- position
- opacity
name 3 radiographic signs of left sided cardiomegaly in a dog
- pronounced left atrium with straightened dorsocaudal silhouette
- dorsal tracheal displacement pivoting at carina
- pulmonary venomegaly & oedema
name 4 radiogaphic signs of R sided cardiomegaly in a dog
- enlarged cardiac silhouette
- pronounced R ventricle
- dorsal tracheal displacement pivoting cranial to carina
- inverse D shape
name 2 radiographic signs of feline hypertrophic cardiomyopathy
- enlarged cardiac silhouette
- pronounced R & L atria (valentine’s shaped heart)
name 2 radiographic signs of canine heartworm disease (Dirofilariasis)
- R heart enlargement (inverse D-shape)
- enlarged and tortuous pulmonary arteries
name 3 radiographic signs of pericardial effusion
- enlarged & round cardiac silhouette
- sharp margins of cardiac silhouette
- indented silhouette margin at diaphragmatic/sternal contact
name the term
incomplete maturation of cartilage into bone;
very rare in cats
osteochondrosis
name the term
when osteochondral fragment separates from subchondral bone
Osteochondrosis dissecans (OCD)
name the term
increased laxity of the hip joint;
most common orthopedic condition in dog, rare in cats;
leads to subluxation & DJD
hip dysplasia
The femoral head should be covered by how much of teh dorsal acetabular edge on radiograph?
at least 50%
on a radiograph of the hip, where should there be parallel femur and acetabulum margins at?
cranial acetabular edge
this is a caudal curvilinear osteophyte on a hip radiograph;
earliest osteophyte, prognostic indicator for developing DJD
Morgan line
name the hip dysplasia scoring method
3 radiographic views (hips extende, distracted, compressed);
static and dynamic joint laxity;
greater than 4 months of age;
only by certified vet;
Distraction index (DI) = degree of subluxation;
results given in relation to all dogs of breed in database
PennHIP method