thorax Flashcards
Kilovoltage peak (kVp)
-voltage difference from filament to anode
* Penetration power or strength of the X-ray beam (quality of the beam)
* for larger areas and body parts such as thorax
Milliamperage (mA)
-electric current through the filament
* Number of X-rays being produced (quantity of the beam)
* High kVp (80-120 kVp) and low mAs (1-5 mAs) are used for thoracic radiographs
Exposure time (s)
-how long X-rays are produced for
*decrease in (s) to reduce motion blur (respiration)
standard thoracic rad views
Radiographic positioning for thorax RL or LL views
- Right lateral view (R)
- Right lateral recumbency
- Thoracic limbs pulled cranially
- Field of view (FOV)
- Just cranial to the thoracic inlet
- Few centimeters caudal to the
last rib
what radiographic markers to place in RL or LL
How to distinguish R from L lateral view?
radiographic positioning for thorax VD view
rad positioning for thorax DV view
where to place rad markers in VD or DV
How to distinguish VD from DV?
when to take thorax rads expiration or inspiration?
-Standard radiographs should be taken at the end/peak of inspiration
heart and sizes on thoracic rads
DOGS
* < 2.5-3.5 intercostal spaces (ICSs)
CATS
* < 2-2.5 ICSs
vertebral heart score on thoracic rads
cardiac width on rads normal size
DOGS AND CATS
* CARDIAC WIDTH < 2/3 of the chest wall
locations of the cardiac chambers
caudal vena cava normal diameter
how to view the pulmonary vessels on rads
for diameter: DV is better than VD.
* ARTERIES SHOULD BE
APPROXIMATELY THE SAME
DIAMETER AS VEINS
* BOTH = DIAMETER OF THE 9TH RIB
mediastinum
-divided into:
cranial (cranial vena cava)
middle: (caudal thoracic trachea, cardiac silloquette)
caudal: (caudal vena cava, aorta)
-how much mediastinum you see depends on fat of the animal
trachea
trachea normal variations
flattened trachea due to redundant membrane, normal
trachea rads if you see the right and left main bronchus splitting further apart Y
Inbetween bronci is the L atrium in VD or DV view so if you see left atrium enlargement you will see splitting of the bronchi
Cowboy legs, if L atrium or tracheal bronchial Lymph node enlargement you will see bronchi splitting
collapsing trachea vs redundant dorsal tracheal membrane
the lumen is being narrowed not just the dorsal membrane
esophagus on rads
-normally NOT VISABLE
esophageal dilation causes:
-may occur due to sedation/ GA
-hypothyroidism
-myasthenia gravis
lymph nodes in thoracic rads locations
-in normal thorax only STERNAL LYMPH NODES may be visualized
generalized mediastinal lymphadenopathy
-cranial mediastrinum is widened
-trachealbronchial causes bronchi splitting
diaphragm on rads
-in LL more Y shape, L cruz is more cranial
-in RL more parellel and R is more cranial
pleural space on rads
In normal conditions:
* Not visualized
* Occasionally, solitary interpleural fissure
identified between lung lobes
Abnormal conditions:
* Multiple and easily identifiable
interpleural fissures, fluid or air filling the
pleural space: plural effusion or pneumothorax
thoracic walls on rads in older dogs and cats
thymus on rads
non standard rads views for thorax indications
-Aid in the diagnosis of small volume of pleural effusion, pneumothorax: will see fluid line with pleural effusion
- Reduce effacement of a thoracic mass by pleural effusion
- Complex diaphragmatic hernias
- Unstable patients (eg. respiratory
distress) – standing patient (below)
rads of horses views
4 quadrants: only take LL or RL not both sides unless need to.
-craniodoral: heart, bronchi, aorta
-caudodorsal:
-caudoventral: trachea, aorta, heart, diaphragm
-cranioventral: trachea, lungs, heart
thoracic ultrasound
-used in emergency and resp distress when you cant get a xray
-place probe between intercostal spaces on both sides of thorax
-should see ribs, and A lines in normal conditions
-will see increased intensity with fluid in lungs B lines presenting pulmonary edema or pneumonia
-as disease progresses will have shred signs
-can also see lung nodules or intra-thoracic mass
