week 4: chest (PA Chest and Left Lateral) Flashcards
what are the 2 forms of digital image receptors?
computed radiography, direct radiography
what is the difference between CR and DR?
Both use an IR, but CR needs to have the IR brought somewhere to be processed
what comprises the bony thorax?
sternum, manubrium, xiphoid process;
2 clavicles, 2 scapulae,
12 pairs of ribs, 12 thoracic vertebrae
palpations at base of neck (posterior) will lead you to this anatomical landmark
C7
Mid-thorax corresponds to
level of T7
Xiphoid process corresponds to
level of T9-T10, even T11 or T12
the anterior rib is (superior/inferior) to the posterior rib
inferior (lower)
the thoracic cavity moves in 3 dimensions on inspiration. what are they?
Vertical diameter
Transverse diameter
AP diameter
A general rule of average adult patients is to “show” minimum of _________ of ribs on a good PA chest
10 pairs
what does SID stand for?
source to image distance
how far away from IR is the bucky to be set?
72 inches
why is 72 inches the correct distance for chest xrays
longer SID magnifies less because the xray beam has less divergence
longer SID magnifies less because the xray beam has (more/less) divergence
less
Chest xrays must be taken on _________
full inspiration
for chest xrays, xray is taken in this way: hold breath on the ________ full inspiration
second
All chest radiographs should be taken in the erect position (as pt condition allows) due to these reasons
- Diaphragm is able to move down farther
- Air and fluid levels in the chest may be visualized
- Engorgement and hyperemia of pulmonary vessels may be prevented
PA Projection
minimum SID
72 inches
PA Projection
IR size
14x17 inches
PA Projection
Grid/no grid?
grid
PA Projection
kVp range
110 - 125
Technical factors of PA projection
-Minimum SID
-IR size
-Grid/no grid?
-kVp range
-72 inches
-14x17 inches
-Grid
-110-125
lengthwise IR would be helpful for a patient with a ________ body habitus
hypersthenic
less magnification for heart can occur by using these factors
less magnification for heart → bucky at 72 inches, PA rather than AP
three radiation protection factors for patients
- limit repeat exposures
- collimation
- Gonadal shielding
positioning for a PA projection
-T7 in middle of IR
-round drape/gonadal shielding
-hands on waist
-asking patient to roll shoulders forward
-extend chin
collimation guidelines (from Prof.)
collimation on WIDTH (left to right) not on length
Evaluation criteria for PA Chest
-Entire lungs included
-No rotation
-Scapulae removed from lungs
-Full inspiration
-Equal collimation top and bottom
-No motion
-Exposure factors*
what do you need to do with shoulders in positioning a patient for a PA Chest?
roll shoulders forward
when counting a minimum of 10 ribs, what is important to remember?
counting posterior ribs (on a PA chest, they are the ones that look more “forward”)
what grayscale and contrast type do you want in a chest xray?
long scale, low contrast
For marking a lateral chest X-ray: we mark the side that is ____________ the IR
closest/touching
what marker would you use for a left lateral chest xray?
Left marker
breathing instructions from PA chest (are/are not) applicable to lateral chest
are
bronchitis: an acute or chronic condition in which __________ is secreted into the bronchi, causing __________ and __________; generally involves the _____ lobes of the lung
excessive mucus, cough and shortness of breath, lower
aspiration: occurs when _________ are swallowed or aspirated into the air passages of the _________
foreign objects, bronchial tree
emphysema: an irreversible and chronic lung disease in which air spaces in the ____ become greatly enlarged as a result of _________ and loss of ________. Air tends to _________ during expiration, causing labored breathing
alveoli
alveolar wall destruction
alveolar elasticity
not be expelled
COPD: form of persistent ______________ that usually causes difficulty in ___________; may be cause by emphysema or chronic bronchitis
obstruction of the airways, emptying the lungs of air
what does COPD stand for?
chronic obstructive pulmonary disease
Pulmonary edema: condition of ________ within the lung that most frequently is caused by a backup in _________, commonly associated with CHF
excess fluid, pulmonary circulation
what is the difference between involuntary and voluntary motion as seen on a radiograph?
all anatomy blurry with voluntary
only that anatomy is blurry with involuntary (ex: heart is blurry during an involuntary heartbeat)
on a radiograph, the SC joints are found on ________________ (not precisely _______)
lateral borders of manubrium, midline
No rotation on a left lateral chest x-ray is evident by ______________
superimposed posterior ribs (slide 40 on powerpoint)
with collimation, You __________ collimation in order to _________ field of view
increase collimation to decrease field of view
how can you determine on a chest XR if the patient has cardiomegaly?
if the apex of the heart “touches” the left side of the chest wall
