Equine Radiology Written Portion

Most radiographic studies require at least two views, the common are ..
-lateral -cranial/caudal
What is the number one cause of technical problems on equine radiographs?
Not changes the settings between views
Name five methods of physical restraint of the horse. Which is the best?
1. Halter and lead 2. Shoulder twitch (quick standstill) 3. Lip twitch (rare) 4. lifting opposite leg (tho this often puts handler in line with beam and causes horse to be more fidgety) 5. Move the horse by standing directly infront and grasping halter by cheek pieces (best)
What are the two goals of the horse holder?
1. Maintain the safety of personnel, equipment, and horse 2. Position horse so target limb is directly under it, perpendicular to the floor
What are the two general types of restraint?
1. Physical 2. Chemical
What are four cons to chemical restraint
1. Can make horse slightly unsteady 2. Can make feet difficult to position 3. Horse can be more sensitive to quick movements and loud noises 4. Horse may sweat heavily
What is an advantage to chemical restraints
quick administration with good effects
Name some examples of drugs used for chmical restraint (2)
1. Acepromazine 2. Sedivet (can be comboed for an equine sedation cocktail)
Which drugs are used for chemical restraint at the college?
1. 1 ml Acepromazine IV 2. 0.5 ml Sedivet IV if requireed
What can be done to make the horse more comfortable before the study? (2)
1. Allow the horse to stand quietly in room for a few mins 2. Allow horse to sniff machine
You should always clear the areas of what two types of people before radiographing?
1. anyone under 18 2. anyone unneeded
It is the radiographers responsibility to ensure the safety of who? (4)
1. Themself 2. Coworkers 3. Public 4. Horse
In terms of choosing/preparing an area which two precautions should be taken when performing radiography in the field? (4)
1. Choose area without public access 2. Close doors 3. Hang signs to keep public out 4. Choose area protected by brick or concrete (if near wooden structure check that no one's on the other side)
How must the patient be prepared before radiographing? (4)
1. Remove blankets, bandages, shipping boots 2. Clean hair coat (remove all dirt, mud or bedding) 3. Wipe area of interest with towel or brush 4. Pull shoe and trim hoof (especially for distal sesamoid/phalanx views
What are three types of x-ray machines used in equine radiology?
1. Portable units (best for out and in clinic use) 2. Mobile units (can only be used in clinic but are somewhat movable) 3. Mounted units (wall or ceiling mounted; offer greatest range of positions/exposures; very expensive and in clinic only)
Which x-ray machine type has the power to radiograph chests, pelvis and abdomens?
Mounted units
Name six accessories used with portable machines like the one at the college
1. Cassettes 2. Grids 3. Cassette holders 4. Lead blockers 5. Cassette tunnels 6. Positioning devices
The most common sizes of cassette in equine radiology is __ x ___ and ___ x ___
-8 x 10 -10 x 12
Most veterinarians use a stationary grid to give greater ____ for the _____ views
-detail -navicular
When using a grid normal KV is increased by __
____ blockers are placed under cassettes when radiographing is being done on a ____ _____ to prevent ____ ______
-lead -cement floor -back scatter
What are cassette tunnels?
boxes the cassette can be placed into to facilitate the horse standing on the tunnel and cassette
_____ blocks are examples of equine positioning devices used to assist alignment on ____ views of the limb.
-wooden -distal
It is helpful to assign ____ responsibilities to one person
What are the two types of labels used in equine radiology?
1. Identification 2. Directional
What information does the ID label include?
1. clinic/vet name and address 2. patient and owner info
What information does the directional label include?
1. left or right and front or hind foot 2. Which way the beam is travelling (based on its position on the cassette)
Radiographs that are taken in a ____ _______ ______ stance must be labelled as such
non-weight bearing
Labels are generally placed as ____ or as ____ as possible with ____ always taking precedence
-lateral or as anterior -lateral
All views will have the label placed on the lateral side of the leg with the exception of the ____ view where the label will be placed on the _____ side of the leg
-lateral -anterior
Oblique views are generally taken at a ___ to ___ degree angle to the joint
In ______ views you must indicate which direction the x-ray beam is travellijng through the object to hit the cassette
In the case of ____ views labels will indicate the beams direction
what is the laymens term for the tibia? For the radius?
-gaskin -forearm
Pastern joint is aka the _____ joint
What is the anatomical term for the cannon bone?
third metacarpal (or metatarsal)
We pack the ____ of the frog with ____ for distal/navicular views, why?
-sulci -play-doh -to keep the same density and have no airpockets
Although radiation safety is a consideration, ___ safety becomes the main focus of equine radiology
In a flexed lateral carpus/fetlock view, when we pick up the limb to flex the carpus/fetlock we must make sure to do what? (2)
1. Not abduct the limb 2. Keep carpus/fetlock directly under body
Oblique carpus/ metacarpus/ fetlock views can be either ____ or _____ depending on what
-lateral or medial -depending on which aspect of the palmar surface the cassette is placed on
Where does the beam center on an oblique view of the carpal joint?
-through middle of carpus angled about 45 degrees from dorsal midline
In a carpal skyline view the limb is elevated until the _____ is parallel to the floor. The cassette is placed against the ___ surface of the _____ ______ region and should be as parallel to the floor as possible
-metacarpus -dorsal -proximal metacarpal
In a carpal skyline the x-ray beam is directed toward the ____ surface of the carpus. The angle of it varies according to what?
-dorsal -according to which row of carpal bones are under examination
In a carpal skyline view to highlight the distal row of carpal bones we angle the x-ray beam about ___ degrees to the cassette from ____
-30 -above
In a carpal skyline view the x-ray beam is directed at anbout a ___ degree angle to the cassette in order to highlight the proximal row of carpal bones
For an unobstructed view of the splint bones an ____ view is neccessary. For visualization of the lateral splint bone (MT/MC IV) the cassette is positioned at a ___ angle _____ to the palmar/plantar aspect. For visualization of the medial splint bone (MT/MC II) the cassette is positioned at a ___ angle _____ to the palmar/plantar aspect.
-oblique -45 -medially -45 -laterally
When holding for a flexed view what two safety concerns must be considered?
1. Collimate hands out 2. Wear apron and gloves
The oblique view of the fetlock allows visualization what two bones?
Medial and lateral proximal sesamoid bones
In a ____ view of the navicular bone we use a cassette _____. If possible we want the patient to step ___ slightly so the fetlock is _____
-flexor -tunnel -back -extended
In a flexor view of the navicular bone the x-ray tube is positioned where? At what angle?
-directly behind the foot -65 degrees to the floor
The flexor view gives good visualization of the ____ of the navicular bone. In this view we might have to decrease our ____
-front -source image distance (SID)
When doing navicular shots (other than in the special notched block) what angle do you have the x-ray beam at?
65 degrees from floor