Rad Positioning Extremities Final Exam Flashcards
For the AP projection of the forearm or elbow, the proximal radius and ulna are partially obscured by overlap unless the radiograph is taken with the…
hand supinated
A patient complains of pain in the proximal femur. What exam(s) should be performed?
Femur series, ID blocker by femur head plus a Hip series
What are the routine views for a hip series?
AP and Frog leg
What technical factors will give the shortest scale of contrast?
200mA, 1/4 sec, 72 kVp
What criteria is true for shoulder series?
10x12film placed transversely, 2” above the shoulder, 40” FFD, CR centered to film
The central ray for the AP knee is…
a 5 degrees cephalic tube tilt entering 1/2” below the apex of the patella
To evaluate an inspiratory P-A chest projection the ____ should be visible above the diaphragm?
seven anterior ribs
The external oblique elbow demonstrates what specific anatomy?
radial head
In which view is the greater tuberosity of the humerus seen in profile?
AP external rotation projection
What criteria is the standard procedure for the PA hand position?
10x12 split transversely, C.R. at 3rd MCP
What criteria applies to the standard procedures for unilateral A-P hip projection?
film size 10x12, 40” SID, leg is inverted 15 degrees
The posteroanterior (PA) projection of the wrist in ulnar flexion demonstrates what carpal bone?
scaphoid
When the elbow is radiographed in a lateral projection, what do you see with anatomy?
- elbow is flexed to 90 degrees
- the radius and ulna are NOT superimposed (near the elbow)
- the wrist and hand are placed in the lateral position
- the humerus is placed as close to the table as possible
To double the density of the film you must use which mAs rule?
50% rule
The AP shoulder (internal rotation) best demonstrates a true _____ position of the humeral head?
lateral
On a homblad, what anatomy can you see?
tibial spines, femoral condyles and an intercondyloid fossa
The patient’s leg is fully extended, and internally rotated until the intermalleolar line is parallel to the film. What view is this?
Oblique ankle (aka mortise projection)
When doing a lower leg series on a patient who presents with pain 3 inches distal to the knee joint, what do you do for a lateral view?
7x17 collimation, 40” FFD, and have the ID blocker by the ankle
In taking a lateral projection of the radius and ulna, which portion of the hand is touching the film?
medial
What are the routine views of the calcaneous?
Tangential (axial) and lateral
What are the routine views of the wrist?
PA, lateral and oblique
Which view is done for localization of foreign bodies of the hand?
lateral hand
What is seen with an AP elbow view?
- central ray is through the antecubital fossa
- hand is supinated
- elbow is at the same plane as the shoulder
What are the routine series of the foot?
AP, lateral and oblique
The routine knee consists of how many views?
3
What is the collimation for a lateral chest view?
14x17
In taking an AP projection of the radius and ulna, the hand is placed in what way?
supination
What are the routine views for a hand series?
PA and PA oblique
The AP femur position requires rotation of what magnitude and degree?
5 degrees internal
What criteria do you need to do in setting up a P-A clavicle position?
collimation on part size, 40” FFD, NO TUBE TILT
In a tangential calcaneous, what is the tube tilt?
40 degrees cephalic
What is the tube tilt for the homblad view?
0 degrees
What is the tube tilt for a lateral knee?
5 degrees cephalic
What anatomy is seen on an int. oblique elbow?
coronoid process (external shows the radial head)
What anatomy is seen on an oblique ankle?
mortise
What anatomy is seen on an ulnar flexion view?
scaphoid
What is the rule of 3 for SID/FFD?
an increase in distance results in a decrease in density
When going from 40” to 72” SID, what is the rule of 3 for this?
need to multiply mAs by 3
When going from 72” to 40” SID, what is the rule to 3 for this?
need to divide mAs by 3
An increase in kVp results in an increase in _____
density (because when increasing kVp, more scatter is produced which shows up on a radiograph as shades of gray and each shade of gray)
What is the kVp 15% rule or rule of 10?
increase kVp by 10 increases film density, decrease kVp by 10 decreases film density
With ____ speed screens, crystals are smaller thus requiring more mAs to make them fluoresce
200
With ____ speed screens, the crystals are larger so not as much mAs is needed to make them fluoresce
400
Grids are used for what?
to clean up scatter
What too much developer or too much time in the developer, what happens to the density?
it is increased
What is filtration used for?
to even out radiographic density
What is contrast primarily controlled by?
kVp
What is density controlled by?
mAs
What is the 50% mAs reciprocal rule?
double mAs to make film darker, cut mAs in half to make film lighter
Increased density?
too dark
Decreased density?
too light
Long scale to short scale?
decease kVp and increased mAs
Short scale to long scale?
increase kVp and decrease mAs
When there is the wrong tube tilt or no tube tilt when there is supposed to be, what happens to the film?
there is a loss in detail
For a chest view and increase in ____ is required to adequately demonstrate subtle lung markings
kVp (should only see the first 4 thoracic because of this)
Why are the chest views performed at 72” SID?
to reduce magnification of the heart
Which way does the ID blocker go for PA and lateral chest views?
ID blocker up
How many ribs should be seen in an PA chest film?
7 anterior ribs and 10 posterior ribs
Abdomen series have the ID blocker facing which way?
UP
In an abdomen series, which sex can you use a gonadal shield for?
Males, but only IF it doesn’t interfere with the abdominal anatomy
What if you have a wide chest for a PA chest view?
turn the film transverse with the top of the film being at the top of the shoulders
What are the breathing instructions for a PA and Lateral chest?
deep inspiration and hold
What side is touching the bucky on the lateral chest?
left lateral side
What do you want to see on a Recumbent AP abdomen?
must include the bladder
FLAT PLATE; KUB- kidney, ureter and bladder
What do you want to see on an Upright AP abdomen?
must include the [top of the] diaphragm
What are the breathing instructions for the recumbent and upright abdomen?
Exhale and hold
upright expose on expiration
When do you use a decubitus view?
if you suspect fluid or air is in the lungs
When do you use an apical lordotic view?
if anything is suspected in the apices (it projects the clavicles above the apices)
Which upper extremity views have the film transverse?
Clavicle Int/Ext shoulder Elbow Wrist Hand
Which upper extremity views have the film lengthwise/longitudinal?
Humerus
Forearm
Scapula “y”
What anatomy is visualized for the internal shoulder?
lesser tubercle
What anatomy is visualized for the external shoulder?
greater tubercle
What can be seen with a scapula “y” view?
shoulder impingement syndrome
What anatomy is visualized with the internal elbow view?
coronoid process
What anatomy is visualized with the external elbow view?
radial head
What are the breathing instructions for all upper extremity and lower extremity views?
don’t breathe don’t move
With the AP shoulder with internal rotation, how is the arm positioned?
arm is internally rotated to place the epicondyles PERPENDICULAR to the film
With the AP shoulder with external rotation, how is the arm positioned?
arm is externally rotated until the epicondyles are PARALLEL to the film
What is the position of the scapula for the PA’ “y” view?
scapula is in the lateral position PERPENDICULAR to the bucky
What is the tube tilt for the “y” view?
10-15 degrees caudal
What is the tube tilt for the AP axial clavicle view?
15 degrees cephalic
What is the tube tilt for the AC joint?
5 degrees cephalic
What is the tube tilt for the PA wrist with ulnar flexion?
20 degrees cephalic (up the arm)
What is the collimation of the PA wrist with ulnar flexion?
3x3
How is the hand positioned for the PA hand?
pronated (CR to 3rd knuckle)
For the PA oblique hand, how far is the hand supinated from the PA position?
45 degrees from the PA position
For the wrist series, how should the whole arm be positioned?
the patient must have their forearm and hand in the same plane
For a forearm series, what two structures must be in the same plane?
humerus and forearm
For the AP internal oblique elbow, how must the hand be positioned?
PRONATED
For the AP external oblique elbow, how must the hand be positioned?
SUPINATED
For a senior patient what needs to be potentially decreased?
exposure time (and kVp)
Patient mobility can be the biggest challenge
may need mobilization devices to help with tough positions
What should be a caution when working with pediatrics?
minimize exposure/radiation protection is most important (control the motion)
For a routine Femur series, what anatomy MUST be included?
KNEE
What is the True AP position for the lower extremities?
knee is extended, foot is dorsiflexed and femur is internally rotated 5 degrees (2nd toe pointed up)
What are the views that utilize the True AP position?
Femur, Knee, Leg, and Ankle Views
What is the importance of Internally rotated the legs 15 degrees for an AP pelvis?
Prevents femoral neck foreshortening (or elongates the femoral neck) and it places the greater trochanter in profile
What is the tube tilt for the AP and Lateral knee views?
5 degrees cephalic
What is the tube tilt for the Ap and Internal Oblique foot?
10 degrees cephalic
In the routine leg views, what joint should be included?
joints closest to injury
Why is the holmblad knee view done?
to see the intercondylar fossa and tibial spines
In a holmblad view, what degree do you need between the knee and the CR?
20 degree angle
What is another name for the Internal oblique ankle view?
MORTISE (because all three ankle articulations are included)
With an AP internal oblique the intermalleolar plane should be _______ with the film
parallel
True/False: the Plantar surface of foot should be on top of the cassette and the knee extended
FALSE: Plantar surface SHOULD be on top, but the knee should be FLEXED
For the AP foot, where should the ID blocker be?
away from the toes by the heel
