When are radiographs taken in the horse?
When the lameness has been localized to a specific region and you suspect a boney abnormality
Lateromedial view
0
Where to the markers always go in the plate?
Lateral and if not an option, then dorsal
Positioning equine rule
Horse must stand squarely on the limb being radiographed.The plate is ALWAYS medial and almost always plantar/palmar because of plate holder danger.
When taking a radiograph of a joint what must be taken into consideration?
It should be as straight as possible in relation to the joint you are trying to image
Observe use of orthogonal and oblique views for complex joints
0
What is going on in this radiograph?
Lack of joint space so there is arthritis of the distal intertarsal joint.
What spot in the tibia is prone to OCD lesions?
medial malleolus
What structure is superimposed in a DMLPO of the tarsus?
calcaneus
In what orthogonal view is the calcaneus bone more clear?
DLPMO
In what orthogonal view does the accessory carpal bone appear lateral and plantar?
DLPMO
what should you do if there are no radiologic abnormalities but you suspect bone injury?
Wait 10 day for a callus formation to form at the fracture line. Osteoclast activity starts eating bone before it heals in a fracture.h
what is the principle behind ultrasonography?
high frequency SOUND waves penetrate tissue and bounce back to the transducer.The crystals in the transducer convert sound waves to electric current. The computer then converts the electric current to an image.
What does the sound wave travel like through air, liquid and bone?
Air and bone: cannot penetrate so it bounces back giving one hyperechoic line at the surface. (example: lungs)Liquid: it bounces back some but it can travel better and generate an image.
Ultrasonography terminology
0
What is the procedure for an U/S of the equine limb?
Clip hairRemove grease with alcoholLOTS of gel (lube is your FRIEND)8-15mHz transducerstandoff provides better detail in areas with less soft tissue (tendons)
with increasing MHZ of a transducer, how does the image change?
DECREASE depth and INCREASE resolution.
where is the most common place for injuries to happen and how does it look like and why?
center of the tendon, it looks hypoechoic and because they fill with fluid.
Fiber alignment and echogenicity on longitudinal view of an injury
0
In how many views does the lesion need to be observed to be confirmed?
TWOadvice: when you find a lesion, try pretending is not there until are proved otherwise.
When is nuclear scintigraphy recommended?
- When the lameness cannot be localized- When the lameness has been localized but no lesions can be found on radiograph or ultrasound- When the lameness is in multiple limbs- When the issue is in the upper limb or axial musculoskeletal issue- There is a suspected fracture but cannot be found in radiograph
What is the most common drug used for nuclear scintigraphy?
Technetium-99m (99mTc)
What certain tissue does the drug for nuclear scintigraphy have propensity for? why is it important?
methylene diphosphonate- hydroxyapatite in boneHydroaxyapatite is formed by osteoblasts in areas of active bone formation (proportional to bone resorption)
What is the principle behind nuclear scintigraphy?
Gamma camera detects decay of radioactive atoms.increased in bone activity --> increase uptake --> increase atom decaying --> increase signal
Normal vs abnormal nuclear scintigraphy
0
What is CT used for in equine medicine?
Detailed evaluation of bone and soft tissue with contrast agentFracture repair planningImage of the navicular apparatusImage of the head
What is the principle behind CT?
X-ray tube rotates in the circle at a predetermined speed. The intensity of the xray allows for differentiation of structures. The computer then reconstructs the data acquired from the detectors to make a slice image which the software program reconstructs in 3D form.
What imaging is limited to with using CT?
carpus, tarsus, distal limb and head
What is MRI used for in equine medicine?
To view soft tissue and bone lesions where ultrasound is not possible.
MRI principles
Magnet is applied and protons are excited by a radiofrequency pulse. When the pulse is removed, protons relax and then it emits a signal. Protons in different tissues relax differently.
CT vs MRI image
0
standard views for each joint
0
best modality for each tissue
0