Equine Imaging Flashcards
what are the special considerations that must be made during equine imaging?
physical safety
radiation safety
what are the risks associated with physical safety during equine imaging?
damage to personnel, equipment and the horse itself
why is the risk of injury higher with equine imaging?
radiographs usually performed with the horse conscious and standing
how should physical safety be ensured during equine imaging?
sedate unless horse is very sensible
ensure sedation is deep enough to create compliance but not so deep the animal cannot stand up
carry out procedure quickly and quietly
what should be avoided when performing equine imaging?
loud noises or sudden movements
touching the horse with x ray equipment or cassettes/holders
what must you always be ready to do when imaging horses?
be ready to move x-ray equipment out of the way if the horse moves or kicks
why does equine radiation create bigger radiation concerns than smaller animals?
people in room with animal
large exposure values due to thicker tissues
large amount of scattered radiation
how can exposure risk during equine radiography be reduced?
minimise number of people around the horse
ensure all involved are wearing protective clothing and dosimeters
how many people should be involved in equine radiology?
3 - one at head, one holding plate, one radiographer
what type of primary beam is often used during equine imaging?
horizontal
how can radiation safety be ensured when using a horizontal x ray beam?
ensure x ray beam is pointing towards a substantial barrier (wall)
ensure no part of a person is in the line of the primary x ray beam
what is the benefit of using cassette holders over having staff hold cassettes?
keeps personnel away from x ray beam and reduces risk from scatter
what must be worn when standing close to the primary beam during equine x ray?
PPE - lead apron, thyroid protector and gloves
how should the horse be prepared for radiography of the foot?
brush off mud
remove shoe (if it will obscure required structure)
pick out hoof
pack frog
mark hoof wall/coronary band/point of frog
why may you want to mark hoof wall/coronary band/point of frog when imaging a hoof?
reference points (e.g. if looking for dropped coffin bone)
how many projections are usually taken for lower limb of the equine?
4 minimum
how many projections are usually taken for the upper limb of the equine?
2
what are the 4 main projections of the lower limb?
lateromedial
dorsopalmar/plantar
dorsomedialpalmaro/plantarolateral
dorsolateralpalmaro/plantaromedial
what are the projections used for full assessment of the equine foot?
lateromedial
dorsopalmar/plantar
60 degree dorsoproximal-palmarodistal oblique
45 degree palmarproximal-palmarodistal oblique
what is imaged during a 60 degree dorsoproximal-palmarodistal oblique projection of the foot?
distal phalanx
navicular bone
what is viewed during a 45 degree palmarproximal-palmarodistal oblique projection of the hoof?
skyline navicular bone
what projections of the fetlock are taken of during imaging?
lateromedial
dorsopalmar/plantar
DLPMO
DMPLO
how can dorsopalamar/plantar views of the fetlock be made clearer?
angle 10 degrees distally to increase separation between joint spaces and sesamoids
what projections of the carpus would be taken initially?
standard 4 (LM, DP, DLPMO, DMPLO) flexed dorsoproximal - dorsaldistal obliques (skyline)
what is the purpose of flexed images of the carpus?
separates radial and intermediate carpal bones
see more of joint surfaces
what is the purpose of dorsoproximal - dorsaldistal obliques (skyline) views of the carpus?
shows dorsal surface of each particular bone / row in the carpus
what projections of the carpus are usually taken?
4 standard usually adequate
what additional projections on top of 4 main ones may be taken of the tarsus (hock)?
flexed views of calcaneus and sustentaculum tali
what are the 2 standard projections of the stifle?
lateromedial
caudocranial
what should be done during caudocranial projections of the stifle to align with joint?
angle 10-15 degrees down
can a cassette holder be used during stifle imaging?
no - must be held
what are the common projections for imaging the elbow and shoulder?
mediolateral
craniocaudal both with leg extended
what is the most common indication for elbow and shoulder images?
history of trauma and suspected fracture
why is it so difficult to image above the shoulder/stifle of a horse?
positioning difficulties
scatter risk
thickness of tissue
how is the thorax imaged in adult horses?
jigsaw of 4 images
what are the 4 projections used to image the thorax of an adult horse?
dorsocranial
dorsocaudal
ventrocranial
ventrocaudal
how can the thorax of a foal be imaged?
possible to image the entire thorax on one plate
how should images of the vertebral column in horse be taken?
in small chunks
markers can be used to ensure no area is missed
what are the main indications for imaging of the head?
sinuses teeth gutteral pouch trauma assessment TMJs
what are the standard projections used to image the equine head?
lateral
DV
oblique
what are the issues associated with ultrasound of a horse?
lots of hair, thick skin and dirt make contact difficult and so image quality low
big patients - low frequency used so image quality low
how should a horse be prepared for ultrasound?
clip if possible
scrub (if unable to clip to wet down hair)
spirit applied to reduce grease on skin
contact gel
what are the main areas that are scanned by ultrasound in horses?
MSK
abdomen
what is ultrasound of the equine abdomen usually looking at?
colic related - motility, dilation and contents of intestine
