Chest X ray Flashcards
definition and background
they have been used for over a century, they are electromagnetic waves, a CXR is a procedure by the electromagnetic beams passing through the thorax and exposing photographic plate. usually taken whilst on deep breath in
what is the X ray image based on
it is based on the anatomy of the patient blocking the transmission by varying degrees, which results in an image caused by the degree of exposure of the plate, the plate turns black (from grey_ as the X-ray strikes it, each body tissue has a different radio-density
radio density
less dense tissue such as air or air filled structures are referred to as radiolucent (black- lets ray through), more dense structures are referred to as radiopaque- white
4 basic radio-density- gas=black-lungs, fat- grey-lipid tissue, soft tissue- grey- heart, bone ormetal- white- ribs or sternum
types- AP, PA
PA- most common- x ray passes posterior to anterior with the plate anterior to the patients chest. patient is upright and the scapula are rotated away from the lung field
AP= commonly used for portable CXR’s. X=ray passes A to P. heart size is magnified done when patient isn’t well- cant move
types- lateral, lordotic and oblique
lateral- allows visualization of lung bases and lung tissue behind heart- taken laterally
lordotic- provides better view of the lung apex, lingula and right middle lobes
oblique- is used to project abnormalities away from overlying structures
types- expiratory, lateral decubitus
expiratory- is used to demonstrate a small pneumothorax or unilateral airway obstruction, lateral decubitus- is used to identify presence of free pleural fluid or to common an air-fluid level- lay on bed and on side
quality- over-exposed
the number of rays (frequency) is too high- higher effect on plate-black, or the length of time the rays have passed through somebody is too long- more time to hit plate- black
quality- under-exposed
not enough intensity, not exposed patient long enough- plate doesn’t change colour
why don’t you want rotation whilst the X-ray is being taken
more likely to occur with AP- more mobile, as structures don’t appear as they should be, to see this look at the clavicle- look to see if the ends of the clavicle are qual distances from SP
what things can you see on X Ray
trachea, the hila, lungs, diaphragm, heaty, aortic notch, ribs scapula, breast tissue, stomach
invisible structures on X-Ray
sternum, oesophagus, aorta, pleura, fissure, detail of spine- lot of dense structures all in one place- similar in radiodensity
interpretations
who- is the patient, check the hospital number/DOB, what- has been X-ray ahs been taken, when- when was it taken, was it post op? and how has it changed, why- was the film taken? was it routine or change in clinical state?
how- position patient in? ward or critical care? AP or PA? how well?- over/under exposed
a systematic approach- A, B, and C
Alignment- is it straight film? look at the proximal end of clavicle and SP?
B- bones- are they all there, intact and normal?
C-Cardiac/mediastinum- is there a clear heart border? is it a normal size (1/3), anything to note in the mediastinum> is there evidence of shifting structures?
a systematic approach- D and E
D- diaphragm- are both hemidiaphragms clearly visible? what about angels, cardiophrenic, costophrenic? right should be higher
E- expansion- how well expanded is the chest? the 10th rib posteriorly should bisect the right hemidiaphragms at mid clavicular line and its 6th rib anteriorly
a systematic approach- F and G
fields- are lung fields clear? are there any areas where the density either increases or decreases? can you see lung edge? fluid level?
G-gadgets- drips, drains, tubes, lines, and other gadgets are visible? are they in, on or around the patient?
