Radiography and Radiology Flashcards
Name the 3 aims of radiography in the horse
- Minimal exposure / risk to staff
- Good, diagnostic films of region of interest
- As little repetition of views as possible – minimum number of exposures possible
How do we acheive: (4)
- Minimal exposure / risk to staff
- Good, diagnostic films of region of interest
- As little repetition of views as possible – minimum number of exposures possible
- Careful attention to protocols and safety
- Good selection of cases for radiography (no safaris!)
- Careful positioning and technique
- Accurate records of exposures and equipment settings
We beam should we consier using? (especially on a yard)
Horizontal beam
What is the inverse square law?
Double the distance = 4 x less exposure
Who should be around when radiographing.. who shouldn’t?
Minimum number of staff (>18, not pregnant)
What do we ned to set up when radiographing on a yard?
Temporary controlled area
What do we use to centre the beam?
Markers on the horse
What do we need to measure for horse x-ray? What is this?
•Careful measuring of fim focal distance (plate to X-ray head)
What 3 things should we write down?
- Record case details, exposures and outcome
- Clearly label radiographs (patient, date and leg)
- Careful storage of radiographs (legal records)
What 4 things do we need to desrcibe about radiograph films when interpreting?
- Animal
- Region
- Views
- Film faults
When interpreting radiographs what 5 things do we Describe the lesion?
(Roentgen signs?)
- Position
- Number
- Size
- Shape
- Radiopacity
After interpreting a rdiograph, what are the next 3 steps?
Develop a list of differential diagnoses
Decide any further diagnostic tests
Arrive at the most likely diagnosis
How do you interpret bone on radiographs?
- Sharp vs. Fuzzy = inactive vs. active, acute vs. chronic
- Smooth vs. irregular = acute vs. chronic
- Mineralised opacities with medullary pattern = fractures
- Subchondral bone defects = osteochondrosis, fracture bed
What may a cystic lesion be on a bone? (2)
- Osteochondrosis
- Subchondral bone cyst
What may a bone radiolucent line be on radiograph? (2)
- Fracture
- Artefact
What changes would you be able to see with soft tissue on radiographs? (3)
- Swelling
- Presence of air or foreign body - puncture wound
- Mineralisation - dystrophic calcification
How many views must an abnormality be seen on equine radiograph?
2
Why is it so important to evaluate areas with a high prevalence of certain disease with equine?
As the performance demands on animals mean that we may be looking for early and subtle changes
What are the potential causes of radiographic changes? (5)
- Trauma
- Infection
- Degeneration
- Developmental
- Neoplasia
What does DLPMO oblique highlight?
Dorsomedial and palmarolateral aspect
What does the DMPLO oblique view highlight?
Dorsolateral and palmaromedial aspect
What view is this?
Upright oblique view of the pedal bone
Which palmar process if fractured?
Lateral palmar process
What is this a radiograph of?
Hock
What does a DLPMO view of the hock highlight?
The dorsomedial aspect and the plantarolateral aspect
What is visible on the DLPMO view of the hock:
A) Dorsally? (4)
B) Plantar? (3)
A) Medial trochlear of talus, central tarsal bone, third tarsal bone and third metatarsal bone
B) Calcaneus, 4th tarsal bone and 4th metatarsal bone
What does the DMPLO view of the hock highlight?
The dorsolateral aspect and the plantaromedial aspect
What is seen on the DMPLO view of the hock:
A) Dorsally? (4)
B) Plantar? (3)
A) Lateral trochlear of talus, central tarsal bone, third tarsal bone and third metatarsal bone
B) Calcaneus, 2nd tarsal bone and 2nd metatarsal bone
What view is this and what is wrong?
Upright navicular view
Radiolucent line proximal to distal border -#
Multiple, variable size and shape areas of sclerosis
What view is this? what is wrong?
CdCr view
Cystic lesion
What is a mach line?
Bone overlying another line = artefact
What should we be aware of when radiographing after a nerve block?
Gas pocket artefact
Whats the matter here?
Large swelling on back of pastern
Whats the matter here?
Irregular new bone on dorsal aspect
= fracture
What is the matter here?
Irregular new bone on dorsal aspect
= infection
What view is this?
Dorsoplantar view (as you can see splint bones)
What view is this?
DLPlMO
Which view is this?
DMPlLO (PlLDMO)
A) Which view?
B) Outline the 4 main joints
C) Which joints communicate?
A) Latermedial
B)
- Tarsocrural joint
- Distal intertarsal joint
- Proximal intertarsal joint
- Tarometarsal joint
C) Distal intertarsal and tarsometatarsal communicate only in some horses
What view is this of the carpus and why?
2 splint bones
Dorsopalmar
Accessory carpal bone is lateral
DLPaMO view highlights the dorsomedial aspect and the palmarolateral aspect:
A) What is seen dorsally? (3)
B) What is seen on the palmar aspect? (4)
A) Radial carpal bone, 3rd carpal bone and 3rd metacarpal bone
B) Accessory carpal bone, ulnar carpal bone, 4th carpal bone and 4th metacarpal bone
PaLDMO (DMPaLO) view highlights the dorsolateral aspect and the palmaroromedial aspect:
A) What is seen dorsally? (3)
B) What is on the palmar aspect? (4)
A) Intermediate carpal bone, third carpal bone and third metacarpal bone
B) Part of accessory carpal bone, radial carpal bone, 1st and 2nd carpal bones and 2nd metacarpal bone
What view of the carpus is this?
- This view highlights the accessory carpal bone (ACB)
- ACB is palmar and lateral
- This is therefore a DLPaMO
A) Outline the 3 main joints of the carpus
B) Which joints communicate?
A)
- Radiocarapl
- Medial carpal
- Carpo metacarpal
B) Carpometacrarpal and middle carpal
Describe and interpret this radiograph. Give the most likely differential diagnosis.
History:
Older horse
Responded to abaxial nerve block and positive response
Horse
Lateral medial image of the foot
No artefact
Soft tissue – see the capsule and pastern
Long toe; low heel toe confirmation
Lucent areas in hoof capsule – nails and have air artefact
Joints – line distal P1 and distal P2 – bit of Proximal distal rotation. Had to interpret bone
Bone – P2 has a smooth new bone on dorsal aspect of P2. The lip is normal
Extensor process – new bone formation on P3. Radiolucency
Palmar processes are heading down –they should never do this and should be 3-10 degrees the other way
NB – kind of normal but heading into distal extension
Distal sesamoid lig originates here – may be
Smooth new bone on proximal aspect of the NB
Cortex, subchrondral area etc normal
Top D/Dx = OA/DJD of DIP
Prognosis – not great
Describe and interpret this radiograph.
Give the most likely differential diagnosis.
History:
Horse was kicked
LF DLPaMO horse
Highlights DM and PaL
Soft tissue swelling
Joints – normal
Bones – Palmar lateral surface = 4th metacarpal bone
Irregular new bone on proximal pal lat aspect. Radiolucency and increased opacity with it
D/Dx – fracture of splint bone with bridging callus
What is the difference between radiography and radiology?
Radiography – taking x-ray
Radiology - interpreting
