Imaging and Pathological correlates of clinical disease Flashcards
Which brain tumors are often extra-axial
Choroid plexus tumors and meningiomas
When would stroke not be on differential list?
If there is a chronic history
How do you treat brain tumors near brainstem?
Radiation- poor candidates for surgery
What is a common sequele to radiation therapy?
Otitis interna/media due to causing local inflammation
-edema in the brain
What causes palor of tissue on histopath?
Edema
Where are the locations of central vestibular lesions affecting the cerebellum?
Floculonodular lobe or caudal cerebellar pedal
What can cause a ring like appearance on MRI?
Microcystic meningioma as well as gliomas
What can vacuolization be a sign of?
Edema, or wallerian degeneration
Define Wallerian degeneration
Antegrade degeneration of the axon distal to a lesion
What does the babinski reflex tell you?
Upper motor neuron sign, tells you that there is a chronic injury present
How do you know if a multifocal spinal chord lesion is present in a patient?
If the grade of weakness in the front or back legs is more than one grade worse than the other
What causes shiff- sherington posture?
Acute T3-L3 lesion
What are some of the differentials for a dog with an acute, non painful spinal cord disease in the T3-L3 region?
FCE, ANNPE, HNP
-ichemic myelopathy
-myelitis
-IVDH
-neoplasia
Which causes hyperintensity of the cord above the disc vs between discs
ANNPE and HNP cause hyperintensity directly centered over the disc, FCE between discs
Why does grey matter die first in FCE cases?
It is more metabolically active and more easily affected by changes in blood supply
What is the pathogenesis of FCE?
An emboli causes a blockage of the spinal cord blood supply, leading to malacia/necrosis
-usually there is more than one emboli affecting multiple regions
Where do the majority of emboli in FCE cases come from?
The nucleus pulposis, followed by vertebral endplate and metaplastic vascular endothelium
What are the theories behind how FCEs enter the spinal cord?
-Direct penetration
-Chronic inflammation and neovascularization of degenerate discs
-Embryonic remnant vessels present in annulus
-disc herniation into vertebral body sinusoids (Schmorls node) and retrograde entrance into the vertebral venous plexus
Why do discs tend to herniate dorsally?
The dorsal annulus is the thinnest part of the annulus
What will you see on MRI of a patient with ANNPE?
A site of hyperintensity in the spinal cord overlaying a degenerative disc
How do you treat FCE/ANNPE cases?
Conservative management
What is the typical presentation for FCE/ANNPE cases?
Dog screamed and then became paraparetic on hind limbs
What percent of dogs that retain voluntary motor function after FCE will recover?
The large majority! 88%
What breeds are typically affected by FCE, ANNP, HNP?
Non- chondrodystrophic breeds
-occurs in healthy animals that put supraphysiologic force on its spinal column causing contussive forces
-cant do anything about these surgically
Describe the pathogenesis of degenerative disc extrusions/protrusions
Degenerative discs that rupture into the spinal cord area causing compression
- can address compression with surgery
What is the main differentials for a young cat with multifocal CNS disease?
FIP, meningoencephalitis, toxoplasmosis, neurodegenerative disease (lysosomal storage disease), nutritional (thiamine deficiency)
With enlarged kidneys, which two differentials do you think of first in a young cat?
Lymphoma or FIP
What type of inflammation is common in FIP cases?
Pyogranulomatous inflammation
What MRI changes are expected in a cat with FIP?
Vasculitis pattern of changes
- CSF does not null out on the flare image
What is expected on analysis of CSF of an FIP kitty?
Marked pyogranulomatous pleocytosis
What is the prognosis for IVDD with disc herniation without deep pain after surgery?
About 50% chance of walking again
What is the main long term concern with severe spinal cord injury?
Development of myelomalacia
What do you often see on MRI of patients with myelomalacia?
Blood (hypointensity) as well as hyperintensity of several regions of the spinal cord
Is there a treatment for myelomalacia?
NO- recommend euthanasia due to shit prognosis
What clinical signs can point you towards a diagnosis of ascending and descending myelomalacia?
migration of loss of cutaneous trunci reflex cranially, loss of pelvic limb reflexes, flaccid abdomen
-abdominal breathing, depression
How long can it take an animal with spinal cord injury to manifest with myelomalacia?
Up to 2 weeks
Which breed of dog is at the highest risk for development of myelomalacia?
French bulldogs
What does a head turn usually indicate?
A forebrain lesion
Which is more common in dogs, immune mediated inflammatory disease or infectious?
Immune mediated
What do you often see in cases of MUE on MRI?
diffuse hyperintensity on T2
- often bilateral, multifocal
-results in contrast enhancement
What would you expect to find on CSF tap of patient with MUE?
-albumocytologic disassociation
-pleocytosis
What is the treatment for MUE?
Steroids + another drug
What is the prognosis for MUE?
Most dogs will die in acute period
What is the main histologic finding in MUE cases?
Perivascular cuffing
What is the most common variant of MUE?
Granulomatous meningioencephalitis
What is the most common cause of spinal cord disease in cats?
Inflammatory lesions
