Adaptive Chest Flashcards
Where should you attempt to Center for a mobile Chest xray
Mid sternum, Perpendicular to the IR. Per Merrills approximately 3” below the jugular notch
What happens to the lung fields in a supine chest xray
They appear shorter due to gravity
What happens to the clavicles in a supine chest xray
They often appear more horizontal and obscure the lung apices more
On the AP projection of a chest how will the scapulae be demonstrated
They will be over the lung field
What is the exposure maintenance formula
mAs1/mAs2 = (D1/D2)^2
OR
new mAs= Old mAs x new distance^2/old distance^2
What is a more efficient method of remembering how to change the mAs for various SID
If we assume 100cm is the starting point, to change to an SID of 130 we will x1.5,
to change SID to 150 we will x2
to change SID to 180 we will x3
Using this method if a chest xray was taken at an SID of 150 at 12mAs, how will we adjust technique to be the same at an SID of 180
Adjust mAs to be 18mAs
If a site does not have virtual grids do we still need to use one
yes
How do you adjust the technique for a grid at 85kVp
No grid x1
5:1 grid x3
8:1 grid x4
12:1 grid x5.5
16:1 grid x6.75
How do you adjust technique for grid at 110kVp
No grid x1
5:1 grid x3
8:1 grid x4.25
12:1 grid x6.25
16:1 grid x8
If an image was taken with 5mAs @ 90kVp and 180cm but you want to add an 8:1 grid how would technique change
20mAs @ 90kVp
If an image was taken with no grid at an SID of 100cm with technique of 6mAs and 90kVp how would you change the techniques to change the SID to 150 and use a grid of 12:1
66mAs @ 90kVp @ 150 SID
Explanation:
Initial 6mAs x 2 to change the SID from 100 to 150 = 12mAs
12mAs x 5.5 to account for 12:1 grid
=66mAs
For a patient who cannot stay still or hold breath for a long time how may we adjut technique
Lower mAs and increase kV
What are 3 tubes you may see on a chest xray
PICC line, ETT tube, Nasogastric tube
Where should we have CR for a pediatric supine CXR
Perpendicular to IR at nipple line
