Exam 1 - Cerebellar Disease Flashcards
what is this posture called?
decerebellate posture
what is decerebellate posture?
cerebellum is pulled off of the brainstem
hind legs are tucked up into the animal & forelimbs are extended/rigid
what are the abnormal signs typically associated with cerebellar disease?
gait - hypermetria/dysmetria
abnormal posture
some cranial nerve responses - menace & vestibular signs
intention tremors
what are the normal signs typically associated with cerebellar disease?
normal mentation
amount of voluntary movement
spinal reflexes
may have normal postural reactions
what is the most common CNS cause of tremors?
cerebellar disease
other than cerebellar disease, what other CNS problems can cause tremors?
steroid responsive tremor syndrome
myelin dysfunction
motor neuron/axon dysfunction
what are some examples of things that look like tremors but aren’t tremors?
partial seizures
idiopathic head bobbing
myoclonus - chronic distemper
what tremorogenic toxins can cause systemic tremors?
mycotoxins - fungal toxins
metaldehyde
permethrin/pyrethrin in cats
what can cause systemic tremors?
catecholamines - very stressed animals (no seizures)
hypocalcemia
tremorogenic toxins
what breeds are associated with idiopathic head bobbing?
boxers, bulldogs, & dobermans
when is the typical onset of idiopathic head bobbing?
near maturity or young adulthood - may wax & wane over the years
T/F: in idiopathic head bobbing, animal behavior remains normal
true
what are 4 examples of non-progressive cerebellar disease?
trauma
toxic insult
vascular insult
congenital anomaly
what are examples of progressive causes of cerebellar disease?
degenerative - forms normally & shrinks (middle to late adult, staffies)
metabolic
nutritional
neoplastic
immune-mediated
infectious
congenital anomaly
what breeds are predisposed to cerebellar cortical abiotrophy?
rhodesians, bernese mountain dogs, staffies, gordon setters
what breed has defined criteria for cerebellar cortical degeneration?
american staffordshire terrier
what CNS cells are among the first to be affected in cerebellar disease? why?
purkinje cells - they are large & have a high metabolic need, so they are typically first affected by inborn metabolic errors or storage diseases
what is neuronal ceroid lipofuscinosis?
degenerative cerebellar disease - can cause retinal changes
thiamine deficiency effects what part of the CNS?
gray matter nuclei in the brainstem & cerebellum
out of dogs & cats, which are more susceptible to thiamine deficiency?
cats
what is the prognosis of thiamine deficiency?
treatable - good prognosis
what drug targets vestibular structures causing cerebellar disease?
metronidazole
T/F: choroid plexus tumors can be either benign or malignant
true
how are choroid plexus tumors diagnosed?
spinal tap of CSF
how can choroid plexus tumors spread?
shed & spread in CSF
how can you treat a choroid plexus tumor palliatively?
aim to decrease CSF production
what other treatment options are available for choroid plexus tumors?
chemo, radiation, surgery (maybe - depends on location)
treatment may extend median survival time, but it’s not considered curable
what inflammatory immune-mediated disease was previously called little white shaker?
steroid responsive tremor syndrome
what virus can cause cerebellar disease in dogs?
canine distemper
what are 2 protozoal causes of cerebellar disease?
toxoplasma & neospora
why is steroid responsive tremor syndrome hard diagnose with MRI & CSF analysis?
MRI - may have no obvious abnormalities especially at low magnet strength
CSF - up to 50% have normal CSF & abnormalities may be non-specific
how is steroid responsive tremor syndrome diagnosed & treated?
immunosuppressive therapy - 2mg/kg/day prednisone with most dogs responding favorably within 2-4 days
unlike MUO, lifelong therapy may not be needed
if you have a dog with suspected steroid responsive tremor syndrome that you’re treating with steroids, what should you do if you think the animal is better & you want to stop the medicine?
taper them slowly over several months
what artery is usually involved in a vascular insult to the cerebellum?
rostral cerebellar artery - usually ischemic
what is the prognosis of a vascular injury to rostral cerebellar artery in dogs?
good - look for & treat the underlying cause
how does dandy-walker-like syndrome?
genetic error leads to an absent vermis
how is dandy-walker-like syndrome different from cerebellar abiotrophy?
can look like abiotrophy on imaging, but dandy-walker-like syndrome is non-progressive
what dog breed is associated with dandy-walker-like syndrome?
eurasier
what is another name for chiari-like malformation?
caudal occipital malformation syndrome
what does caudal occipital malformation syndrome affect in the CNS?
affects the cerebellum but doesn’t typically cause cerebellar signs
T/F: caudal occipital malformation syndrome causes cerebellar signs
false - affects the cerebellum but doesn’t cause cerebellar signs
T/F: caudal occipital malformation syndrome is breed associated
true
how does caudal occipital malformation syndrome occur?
has to do with skull suture closure times
why does caudal occipital malformation syndrome cause problems in dogs?
change in the flow of CSF which leads to the dilation of the 3rd ventricle
what are the most common clinical signs of caudal occipital malformation syndrome?
non-dermatological pruritus
cervical pain
cervical scoliosis
what is the difference between decompression & shunting in surgically treating caudal occipital malformation syndrome?
the syrinx doesn’t resolve with decompression
what is the general treatment for caudal occipital malformation syndrome?
surgery - usually successful & has a good prognosis
what may be the downfall of treating caudal occipital malformation syndrome surgically?
may require revision & repitition over time
what medications can you use to treat caudal occipital malformation syndrome?
anything to decrease CSF production - diuretics, omeprazole, steroids (0.5 mg/kg/day)
what 4 questions should you use when approaching cerebellar disease?
- is it cerebellar disease?
- progressive or non-progressive - prioritize your differentials
- choose diagnostics based on prioritized differential list
- remember that diagnosis is important even in untreatable conditions
