Portable x-ray machines should be used with a stand. Why?
The stand helps avoid radiation exposure
what color film should be used with rare earth screens?
Green
The speed of the screen affects what?
The radiation exposure needed
CARE OF SCREENS:
After cleaning the cassette should be stored in a horizontal position until dry?
False
CARE OF SCREENS:
Pressurized air is a good way to remove loose debris on the screen?
True
CARE OF SCREENS:
Scratches, dirt, and chemical spills on the screens could result in a misdiagnosis and potentially unnecessary pain and suffering for the patient.
True
CARE OF SCREENS:Commercial screen cleaners are available for screen cleaning
True
CARE OF SCREENS:
Damage to a screen surface is permanent and cannot be repaired
True
How should you place radiographs on the viewer?
Lateral: Walking off the to the left
VD: Walking towards you
Describe two ways a large animal technique chart differs from a small animal technique chart
No Ma
No abdomen or thorax chart
Describe two indications that tell you that the portable x-ray machine has actually exposed the film
flash of the light
hear the beep
List one indication we use to determine if a lateral fetlock film is a true lateral view and not obliqued.
The sesamoid bones are superimposed on each other
Why do we like rare earth screens so much?
Safer because of less radiation and they are quicker
Explain how grids absorb scatter radiation yet let diagnostic radiation through.
Grids are lead pieces going in a pattern that absorbs scatter radiation
When do we want to use a grid in a radiographic study?
when the patient is bigger than 10cm
Define phosphor
The things that glow in response to radiation
Which of the following anatomical structures should be parallel to the cassette for a well positioned lateral skull film?
The nasal septum
In a lateral pelvic film which leg gets pulled cranially?
The bottom leg
Which bone is superimposed over the center of the distal femur on a well positioned Cr-Ca femur film?
The patella
List the four standard views we shoot of an equine tarsus.
Dp, lateral, medial oblique, lateral oblique
List the five criteria used to determine correct positioning on an OFA style pelvis film.
Patella between femur condyles
nothing is obliqued/everything is straight
Femur is in the middle of the cassette/beam
AOI-Sacrum to stifles
restrained properly
Describe the location for the lables for each of the 3 equine carpal views
Lateral: cranial
DPO: Lateral
Felx: Cranial
Why do we need to use the bisecting angle technique when performing dental radiography?
so we get the whole tooth and the root in one radiograph
Describe two ways to restrain birds for whole body films
tape, lead bags
How do we position the little bump on the dental film?
Rostral and toward the tube
When might a frog-leg position be preferable to the standard OFA type positioning for a VD pelvic radiograph
Broke pelvis
if you are exposing a lateral view of the right femur which side of the patient is the downside?
Right
Why is positioning so crucial with skull radiographs
Because of the different densities
What does collimation have to do with spinal film?
Helps prevent scatter radiation since the spine is small and doesnt need to take up the entire film
What is the name of the DJD that affects some equine distal medial hock joints
Bone spavin
what is the anatomical name for the point of the hock
calcaneous
What is the relationship between the density of an object and its appearance on the film
More density the whiter it is
Why do we care about bubbles on the film
creates artifacts on the film
what color is exposed correctly processed film?
Black
What color is unexposed correctly processed film
White
List two reasons why it is important to stir the developer before placing the thermometer in the tank
Mix the solution and temperature
Why was the shape of the upright bolts different for the different bolt positions
shadowing
What effect would this have on the shape of an organ or bone in a patient
Blurr and even become unrecognizable
What can we do to avoid scatter radiation
Center the AOI and grid
Why are the bolts visible outside the area of collimation?
Scatter radiation
Why do we care about the effect of scatter radiation
unsafe and poor image detail
Define radiographic density
degree of blackness or darkness on a radiograph
Define grid factor
The amount the exposure needs to be increased to compensate for the grids absorbtion of a portion of primary beam
What would film look like if it should be a tabletop film but you use the bucky
Light image
What would a film look like if you were suppose to use the bucky and instead used the tabletop
Darker
what is in the intensifying screens that allow them to flouresce
rare earth
What color of light did the screens produce
tungstate= blue
rare earth= green
Someone ordered the wrong film (blue instead of green). What would look different on a developed film.
Lighter in color
When looking at your developed film, how can you tell if you achieved a true lateral position
The sesamoide bones are super imposed
Why not expose the film as a ML view rather than a LM?
You have to get under the horse for that
ho can you protect yourself from radiation exposure during a fetlock study
Lead, keep out of the beam face forward not backward
List two disease conditions that could cause your DVM to ask you to x-ray an equine fetlock
OCD
Synovitis
List a handling/restraint trick used to encourage horses to bear full weight on the leg you are radiographic
Lift up opposite leg
Why might your DVM request an x-ray series of the carpus
Osteoarthritis
List two reasons why we should use the tripod stand when using the portable x-ray machine
avoid radiation exposure, in case the horse kicks it doesn't get dropped as well
What was the most difficult aspect of patient positioning for the CrCa view of the femur?
Straightening the leg enough to lay flat against the cassette
List the anatomic structures that are included in a good femur film
hip joint full femur stifle joint
If you are positioning a lateral view of the left femur what side of the patient is the downside
left
where do we measure the femur for the CrCa view
Middle where theres more muscle
On a lateral pelvic film what can we do to avoid pelvic rotation and still keep the femurs parallel to each other
wedge foam between the legs
what is the Penn-hip method of screening for hip dysplasia
standard extended
compression with neutral position
distraction with some neutral position
List a urinary tract injury that often occurs with a pubic bone fracture
ruptured urethra
Which radiographic procedure could be used to definitively diagnose this condition
urethography
How do we estimate the bisecting angle
Angle the film the teeth and the middle to find the angle
list two small animal dental conditions diagnosed using dental radiography
gingivitis
periodentis
Why is sedation o anesthesia necessary for good quality head and neck films
controlled patient is vital for precise and symmetrical film
Why is positioning so crucial in skull radiographs
to avoid oblique films
After exposure and developing how can you tell if the VD cervical spinal film is obliqued
you dont have the wings of the atlas symmectrical
List the POM and beam center for a CXR
POM=Caudal scapula
BC= caudal boarder of the scapula
How can we tell from looking at a CXR film that is is well-positioned
The ribs are superimposed and or parrallel
What does the guideline the thorax is inside the rib cage have to do with take a CXR
We need all of the ribs to get all of the thorax
Why do we shoot a CXR at full inspiration
the diaphragm is pushed back away from the heart so we see the lungs at max copacity
How can we tell whether the film is a full inspiration
there is space between the heart and the diaphragm
What are the cranial and caudal anatomical limits for an AXR
Cranial= diaphragm
Caudal= femoral head
List the POM and beam center for an AXR (difference between cats and dogs)
POM: Dogs=caudal aspect of the 13th rib
Cats=Same
BC: Dogs= 13th rib
cats= two fingers behind the 13th rib
Why is it important to pull the hind limbs caudally when positioning for a lateral AXR
Get the legs out of the way
Why is it not important to stretch the hind limbs caudally with a VD or DV AXR
its not in the view
Do we expose AXR on expiration or inspiration? Why
Expiration. diaphragms pushed up and out of the way
What are the 2 standard views for an AXR? why?
Right lateral
VD
you might see something that looks like its deep in the abdomen when its really in the skin
What would an abdomen full of blood (or urine) look like on an AXR why?
No detail no content
Why is it important to fill the frog area with Play-do
Prevents the appearance of an air artifact superimposed over the AOI
List and describe two ways to get a DPO view of the navicular bone
On a cassette in a cassette tunnel on a block with a specially designed grooves that hold the hoof at an angle