Decision making for imaging Flashcards
Describe what you can see on this radiograph and give your diagnosis
Unlabelled lateral radiograph of cat thorax and cranial abdomen
No fractures visible, trachea dorsally deviated, increased opacity of lung fields, cardiac silhouette obscured
Gas and ingesta filled intestines visible in the thorax, can see where they cross the diaphragm
Diagnosis: diaphragmatic hernia
Describe what you can see on this radiograph
Ventro-dorsal radiograph of the pelvis of a cat
Sacroiliac luxation of the right side, with a complete fracture of the ilium of the left side
There is no evidence of acetabular involvement but there is narrowing of the pelvic canal.
Describe what you can see in this radiograph
Can see colon with normal faecal material
gas filled caecum
normal loops of gas filled small intestine – not distended. Urinary bladder and kidneys normal. Within the stomach there is a foreign body – likely a corn cob. Conclusion: Gastric foreign body.
Describe the decision between ultrasound and radiograph when a foreign body is suspected
Radiograph of abdomen will give a global overview but may not see foreign body if not radiodense. We may see evidence suggestive of an obstruction e.g. distended small intestine.
An ultrasound would also be appropriate but due to gas within a normal GI tract there will likely be shadowing which may obscure the foreign body and therefore it may be missed.
The decision between the two modalities is usually based on the confidence of the clinician with each modality and often a combination will be used, beginning with radiography.
Describe what you can see on this radiograph
There is poor serosal detail but there is evidence of abdominal fat ventrally.
There is fat over the lumber region.
The liver is enlarged and the caudal border is rounded in shape.
There is pulmonary calcification.
There is some calcinosis cutis noted within the ventral abdominal skin.
The femur is slightly osteopaenic (low bone density).
Stomach is normal.
Caudal borders of both kidneys are normal.
Bladder outline is normal.
These features are consistent with Cushing’s Disease.
What factors should you consider when choosing an image modality?
Available equipment
Risk to animal and handlers (invasive vs non-invasive tests)
Will the results make a difference to the approach or outcome to the case?
Client finances
Give examples of diagnostic tests you could use in large animals
Radiography
Ultrasound
Endoscopy
MRI
CT
Endoscopy
Gamma scintigraphy
Nerve/joint blocks
Advantages and disadvantages of radiography
Pros: Quick, widely available, good for bones & gas-filled structures
Cons: Limited soft tissue detail, radiation exposure, requires multiple views
Advantages and disadvantages of ultrasound
Pros: No radiation, real-time imaging, great for soft tissues
Cons: Operator-dependent, limited in gas-filled structures, can’t see deep structures well
Advantages and disadvantages of CT
Pros: Excellent detail, 3D imaging, good for bone & lung structures
Cons: Expensive, requires general anaesthesia, radiation exposure
Advantages and disadvantages of MRI
Pros: Best for soft tissue (brain, spinal cord, muscles), no radiation
Cons: Very expensive, time-consuming, requires general anaesthesia
Advantages and disadvantages or endoscopy
Pros: Direct visualisation, minimally invasive, can take biopsies
Cons: Expensive, requires sedation or anaesthesia, limited to hollow organs
A dog presents with a distended abdomen, what are some possible differential diagnoses?
Pregnancy
Pyometra
Ascites (fluid buildup)
Organomegaly (enlarged organs)
Gastric dilation-volvulus (GDV)
Which imaging modality is best for investigating a distended abdomen?
Radiography: Good for GDV, organ enlargement & gas patterns
Ultrasound: Best for fluid accumulation, pregnancy, pyometra
Conduct both for a reliable diagnosis
A pony has become lame on its left fore. The pony is 2/10th lame at the walk, which increases to 5/10th when the distal limb is flexed. There is bony and soft tissue swelling localised around the pastern region joint.
What diagnostic tests will you perform?
Radiograph - bone and joint assessment
Ultrasound - soft tissue assessment
A horse is lame on its left forelimb. Describe these radiographs.
Images clear, with proper exposure, centering & collimation
No artefacts & all images are correctly labeled except dorsopalmar view
Bone fragment visible on dorsomedial aspect of proximal interphalangeal joint
Bone irregularity on dorsolateral edges of P1 & P2, along with new bone formation (osteophytes), which suggests degenerative joint disease process
Describe this radiograph of a horse kick injury
Dorsolateral palmaromedial oblique view of the proximal metacarpal region
Good exposure, centred over kick wound, well collimated, no labels, no artefacts, positioned well
Small area of radiolucency within medullary region of proximal M3
Complete fracture of proximal M4, incomplete fracture of proximal M3
An 8 year old horse has recently developed a unilateral nasal discharge.
What diagnostic tests will you perform
Respiratory endoscopy - assess guttural pouch
Lateral cranial radiograph - assess sinuses and guttural pouch
Describe what you can see in this laterolateral radiograph of the caudal horse head
Soft tissue opacity over area of guttural pouch
Clear radiolucent line suggesting fluid in pouch
Pharynx has been displaced cranially
A 4 year old racehorse has developed soft tissue swelling of the left fore palmar metacarpus the day after racing.
What diagnostic test will you perform?
Ultrasound
Label these transverse and longitudinal ultrasounds of the proximal palmar metacarpal region
