SA Neuro Flashcards
(244 cards)
1
Q
Which diagnostic tests can you use to diagnose neuro conditions?
A
Blood, urine, faecal, microbiology Genetic testing CSF Imaging (US, radiographs, myelography, CT, MRI) Electrodiagnostics Muscle and nerve biopsies
2
Q
What would you look for on a haematology test when diagnosing neuro disease?
A
Infectious and inflammatory dx
Hyperviscosity (polycythaemia)
Inclusions (lysosomal storage dx)
Thrombocytopenia
3
Q
What would you look for on a biochemistry test when diagnosing neuro disease?
A
Liver function (bile acid stimulation test, ammonia)
Glucose and fructosamine (weakness, seizures)
Electrolytes (Na, K, Ca-weakness, seizures)
CK, AST (muscle damage)
4
Q
Which endocrine tests may you run when investigating neuro disease (mainly for neuromuscular disease)?
A
- Thyroid dysfunction
- Adrenal dysfunction
- Insulin
5
Q
Give some markers for immune-mediated diseases
A
- Acute phase proteins (eg C-reactive protein, good for steroid-responsive meningitis arteritis SRMA)
- Acetylcholine receptor antibodies titres (gold standard for acquired myasthenia gravis)
- Type IIM antibodies titres (gold standard for masticatory muscle myositis)
6
Q
How does immune-mediated acquired myasthenia gravis work?
A
Forms circulating antibodies against Ach receptors
7
Q
Which test would you use to diagnose myasthenia gravis?
A
Acetylcholine receptor Ab test= gold standard
Edrophonium test
IV administration of edrophonium chloride (often called tensilon) which is a fast-acting cholinesterase inhibitor
Can have false + and -
8
Q
Give a potential problem with using the edrophonium test to diagnose myasthenia gravis
How would you resolve it?
A
Can cause a cholinergic crisis: bradycardia, salivation, miosis, dyspnoea, tremors
Give atropine
9
Q
Which infectious diseases could cause neuro conditions in dogs?
A
Neospora Toxoplasma CDV (distemper) Cryptococcus Tick-borne diseases
10
Q
Which infectious diseases could cause neuro conditions in cats?
A
FIV FeLV FIP Toxoplasma Cryptococcus
11
Q
Why might you carry out metabolic urine screening?
A
To identify genetic diseases causing errors of metabolism
Most abnormal metabolites are concentrated in urine
Metabolic defects that produce organic acid accumulation often affect neuronal and muscle metabolism
12
Q
Why should you always do a CSF analysis before doing a myelography?
A
The contrast material in the myelogram is irritable and will cause inflammation, which will affect the results of the CSF analysis
13
Q
Where should you collect a CSF sample from relative to the lesion?
A
Caudal to lesion
14
Q
When is a CSF analysis contraindicated?
A
Increased intra-cranial pressure (brain could herniate through skull)
Clotting problems (could cause bleeding into spine -> death)
Chiari-like malformations (syringomyelia)
Atlantoaxial instability or trauma
15
Q
What shoud you never do when taking a CSF sample?
A
Aspirate
16
Q
How much CSF should you take when obtaining a sample?
A
1ml/5kg
17
Q
When taking a CSF sample, why should you use a plastic rather than glass tube?
A
Cells adhere to glass -> may get falsely low counts
18
Q
What should you look at in a CSF analysis?
A
Differential cell count
Cytology
Protein
PCRs
19
Q
What would you expect in a normal CSF sample?
A
<5 WBC/ul
No RBC
Protein <30-45mg/dl
20
Q
What are the 2 places you can take a CSF sample from?
A
Cerebellomedullary cistern (atlanto-occipital joint) or lumbar subarachnoid space (L5-L6)
21
Q
What position should a dog be when you take a CSF sample?
A
Lateral recumbency
Head 90 degrees, nose parallel to table
22
Q
Where would you take a cervical CSF sample?
A
Imaginary line between occipital protuberance and wings of atlas (cerebellomedullary cystern)
23
Q
Where would you take a lumbar CSF sample?
A
L5-L6 in dogs
L6-L7 in cats and small dogs (end of spine) (lumbar subarachnoid space)
24
Q
What size needle should you use when taking a CSF sample?
A
Cervical: 1.5 inch needle, 21-22G
Lumbar: 1.5-3.5 inch needle, 21-22G
25
What is a pleocytosis?
An increased cel count, usually WBCs
26
For which conditions may you see a neutrophilic pleocytosis in a CSF sample?
```
(Increased neutrophils)
SRMA (steroid-responsive meningitis arteritis)
Bacerial infection
Granulomatous meningitis
Necrotising encephalitis
Fungal
FIP
Post-myelography, haemorrhage, trauma, neoplasia
```
27
For which conditions may you see a mononuclear pleocytosis in a CSF sample?
```
Granulomatous meningitis
Necrotising encephalitis
CNS lymphoma
Viral (distemper)
Bacterial and steroid-responsive meningitis arteritis
```
28
For which conditions may you see a mixed pleocytosis in a CSF sample?
```
Granulomatous meningitis
Bacterial and steroid-responsive meningitis arteritis
Fungal
Protozoal
Non-inflammatory disease (infarction)
```
29
For which conditions may you see an eosinophilic pleocytosis in a CSF sample?
```
(Uncommon)
Eosinophilic meningitis
Fungal
Protozoal
Parasitic
```
30
What is myeography?
Administration of contrast agent to subarachnoid space to outline the spinal cord
Highlights space-occupying lesions as deviations or thinning of contrast column
31
CT is good for diagnosing what?
Trauma
Haemorrhage and middle ear disease
Fair for tumours and IVDD
32
What is electrodiagnostics?
Recording of electrical activity of muscles or neuronal structures
Can be spontaneous or in response to stimulation
33
What is electromyography (EMG)?
Records spontaneous muscle electrical activity
Normal muscle at rest is electrically silent
Destabilisation of the muscle cell membrane results in spontaneous discharge and so identifies damaged or denervated muscles and lesions
34
What do nerve conduction velocities (NCV) do?
Evaluate peripheral nerve function by stimulating a nerve at 2 different locations and recording:
- Amplitude of response (strength)
- Latency of response (how long it takes to get there-to calculate velocity)
35
What do velocities and amplitude represent on an nerve conduction velocity test?
Velocities: myelin
Amplitude: axon
36
What do repetitive nerve stimulation tests do?
Evaluate neuromuscular junctions (eg myasthenia gravis)
| If amplitude decreases by >10%, suggestive of disease
37
What do F wave tests do?
Evaluate nerve roots and proximal part of peripheral nerves
| Lost/delayed F waves if nerve roots are damaged
38
What do electroencephalography (EEG) tests do?
Record spontaneous electrical activity in cerebral cortex. 5-12 electrodes on head.
Good for:
-Detecting seizures
-Localising seizure focus
-Monitoring response to AEDs (automated external defibrillators) in cases with epilepsy
-Brain death
39
What do brainstem auditory evoked response (BAER) tests do?
Screening tool for detection of congenital sensorineural deafness
Determines hearing threshold in adults
Assess neural lesions on CNVIII or brainstem
Assess for brain death
40
Why do we take muscle and nerve biopsies when diagnosing neuro disease?
Mainly to differentiate between inflammatory and non-inflammatory (metabolic, degenerative) disaese
41
How big should a muscle biopsy be?
0.5 x 0.5 x 1.0cm
42
How big should a nerve biopsy be?
1/3 the width for 1cm
43
Which nerve is commonly biopsied?
Peroneal nerve (cranial tibia mucsle) (easily identified, is both motor and sensory)
44
Give some neurological deficits of the forebrain
- Altered mental status (depressed/disorientated)
- Contralateral blindness (decreased menace but normal PLR)
- Normal gait
- Circling (ipsilateral), head turn, head pressing, pacing
- Reduced postural responses in contralateral limb (tells you the lesion is rostral to midbrain)
- Normal to increased spinal reflexes and muscle tone
- Seizures, behavioural changes, hemineglect syndrome
45
How would you identify the location of a lesion using postural reactions?
- Lesions rostral to the midbrain (eg forebrain) -> contralateral reduced responses
- Lesions caudal to the midbrain (eg SC) -> ipsilateral reduced responses
46
Give some neurological deficits of the midbrain
- Depression, stupor, coma
- Cranial nerve deficits, possible vestibular signs
- Paresis of all or ipsilateral limbs
- Possible decerebrate rigidity
- Reduced postural responses in all/ipsilateral limbs
- Normal to increased spinal reflexes and muscle tone
- Resp or cardiac abnormalities
47
Opisthotonus with hyperextension of
| all four limbs reflects a lesion where?
Brainstem
48
Give some neurological deficits of the cerebellum
- Normal mentation
- Ipsilateral menace deficit, normal vision, possibly vestibular signs
- Possibly decerebellate rigidity (hyperextended FLs, spastic flexion of hips)
- Intention tremors
- Truncal ataxia, broad-based stance, hypermetria
- Delayed then hypermetric postural responses
- Normal spinal reflexes and muscle tone
- Rarely increased frequency of urination
49
Hyperextension of the forelimbs and spastic flexion of the hips reflects a lesion where?
Cerebellum
50
What is meant by 'white shakers'?
-Idiopathic cerebellitis, idiopathic tremor syndrome
-Mostly small breeds, young dogs
-Fine tremor, worse with stress/excitement
+/- head tilt/decreased menace/ leaning and falling, ataxia
51
How do you diagnose white shakers?
CSF-mildly inflammatory
52
How do you treat white shakers?
| What is the prognosis like?
Corticosteroids for 4-6 months +/- other immunosuppressive drugs
Good prognosis, may relapse
53
What are the 3 main methods of infection of bacterial meningitis?
- Haematogenous
- CSF
- Direct invasion (eg inner ear, eyes, bite wounds)
54
Give some clinical signs of bacterial meningitis
Usually acute:
- Obtundation and cranial nerve deficits
- Neck pain
- Pyrexia
- Neutrophilia (50% of cases)
55
How would CSF be affected by bacterial meningitis?
- Increased protein concentration
- Pleocytosis (increased lymphocytes)
- Phagocytosed organisms (rare)
56
How do you treat bacterial meningitis?
- Antibiotics
- Surgical drainage
- Guarded prognosis
57
Give some clinical signs of increased intracranial pressure
- Altered mental status: obtunded, stupor, coma
- Altered pupil function: anisocoria, miosis, mydriasis
- Posture: decerebrate or decerebellate
- Bradycardia and hypertension (Cushing's reflex)
- Physiological nystagmus
58
What is the oculocephalic reflex?
- When you move head, eyes should follow
| - May be absent in comatose patients with brainstem dysfunction eg head trauma
59
How should you treat a patient with head trauma?
- ABC
- Oxygenation
- Restore blood pressure
- Fluid therapy (avoid glucose)
- Analgesia
60
How would you treat raised intracranial pressure?
- Mannitol (decreases blood viscosity) followed by crystalloid fluid therapy to prevent dehydration eg normal 0.9% saline (CI in hypovolaemia)
- Or hypertonic saline (4mg/kg 7.5% as slow bolus) (CI in hyponatremia)
61
Give some general care you should consider when treating a patient with head trauma
- Keep head elevated
- Avoid jugular compression
- Turn every 4-6 hours
- Catheterise bladder
- Nutritional support (tube feeding)
62
What should you not give to patients with head trauma?
Corticosteroids
63
What is hydrocephalus?
Abnormal dilation of the ventricular system within the cranium
64
Which kinds of dogs are affected by hydrocephalus?
Toy breeds, young age
65
Give some clinical signs of hydrocephalus
- Domed head
- Persistent fontanellae
- Abnormal behaviour
- Cognitive dysfunction
- Seizures
- Obtundation
- Circling/pacing
- Vestibular signs
66
How do you treat hydrocephalus?
- Medical: corticosteroids, furosemide, anti-epileptic drugs
| - Surgical: ventriculoperitoneal shunt (drains fluid from ventricles into abdomen)
67
What is lissencephaly?
| Which breeds are predisposed to it?
- No development of gyri and sulci
| - Llasa apso, Korat cats
68
Give some clinical signs of lissencephaly
-Seizures and behavioural changes
69
What are hydronencephaly and porencephaly?
Presence of cerebral cavities, usually communicating with subarachnoid space and/or lateral ventricles
70
Give the clinical signs of hydronencephaly and porencephaly
- 1st few months: circling, abnormal behaviour
| - Up to a few years: seizures
71
What is hepatic encephalopathy?
Liver dysfunction -> toxins in blood -> brain dysfunction
| -Caused by acute liver failure or congenital portosystemic shunt
72
Give some clinical signs of hepatic encephalopathy
Mostly signs of forebrain dysfunction:
- Seizures
- Circling, head-pressing
- Abnormal behaviour
- Mentation changes (obtundation)
73
How do you diagnose hepatic encephalopathy?
- Blood ammonia levels
- Bile acids
- Liver US or CT
74
How do you treat hepatic encephalopathy?
- Lactulose (reduces absorption of ammonia from gut)
- Antibiotics
- Restricted protein diet
- Anti-epileptic drugs
- Surgery
75
Give the clinical signs of hypocalcaemia
- Muscle spasm and cramping
- Muscle twitching, trembling, stiffness
- Mental depression
- Tonic-clonic spasm
- Episodic rigidity
- Tetraparesis
- Seizures
76
Give the clinical signs of hypercalcaemia
- Muscle spasm and cramping, muscle twitching -Trembling
- Mental depression
- PU/PD
- Constipation
77
Give some causes of hypernatremia (high blood sodium)
- Excess water loss
- Excess salt intake
- Insufficient water intake
- Brain abnormalities
78
Give the clinical signs of hypernatremia (high blood sodium)
-Changes in mentation and seizures
79
How do you treat hypernatremia (high blood sodium)?
Correct sodium levels slowly over 48-72 hours
80
What is a storage disease?
- Defect of a lysosomal hydrolase enzyme
- Accumulation of storage substrates within the cytoplasm (mainly of neurons) -> cellular dysfunction -> diffuse neurological dysfunction -> progressive -> death
81
How do you manage storage diseases?
- No treatment
| - Symptomatic treatment eg anti-epileptic drugs, anti-anxiety drugs
82
Give some causes of hypoglycaemia
Insulinoma, hepatic dysfunction
83
Give some clinical signs of hypoglycaemia
- Anxiety, lethargy, depression
- Ravenous appetite, exercise intolerance
- Tremors, visual deficit, seizures, coma
84
How do you diagnose hypoglycaemia?
Blood glucose <3mmol/L and clinical signs
85
How do you treat hypoglycaemia?
- Direct administration of glucose in emergency
- Frequent feeding in chronic cases
- Treat underlying cause
86
Give some primary neoplasms of the brain
- Intra-axial glial cell tumours
| - Extra-axial meningiomas, choroid plexus tumours
87
How do you diagnose brain tumours?
- MRI (sometimes CT)
| - CSF analysis (to rule out inflammatory disease)
88
How do you treat brain tumours?
- AEDs (anti-epileptic drugs)
- Anti-inflammatory dose of corticosteroids to reduce cerebral oedema
- Surgery +/- radiotherapy
89
What is Lafora's disease?
- Neuronal glycoproteinosis
- Progressive myoclonic epilepsy
- Jerking (myoclonic) which is induced by flashing lights, sudden sounds and movements
- Wire-haired Dachshund and Basset Hound; rare
90
How do you treat Lafora's disease?
- Antioxidant-rich diet
- Avoid starchy/sugary treats
- Treat epilepsy symptomatically (eg KBr)
91
Give some clinical signs of vestibular disease
- Head tilt (ipsilateral)
- Vestibular ataxia and wide-based stance
- Nystagmus
- Leaning and falling, sometimes tight circling
- Positional strabismus
92
Is a vertical nystagmus normally caused by a defect in the central or peripheral vestubular system?
Central
93
What is a cerebrovascular accident?
- Stroke
| - Rapid loss of brain function due to a disturbance in blood supply to the brain
94
What are the 2 types of cerebrovascular accident (stroke)?
- Ischaemic (majority; results from aterial/venous obstruction)
- Haemorrhagic (results from rupture of blood vessels)
95
How do you diagnose a cerebrovascular accident (stroke)?
MRI
96
Give some concurrent medical conditions that could lead to a cerebrovascular accident (stroke)?
- CKD
- Hypertension
- Hyperadrenocorticism (Cushings)
97
What is an MUO?
Meningoencephalomyelitis of unknown origin
98
What are the 3 types of MUO?
- GME= granulomatous meningoencephalomyeitis
- NME= necrotising meningoencephalomyelitis
- NLE= necrotising leucoencephalomyelitis
99
Which kind of dogs are more affected by GME (granulomatous meningoencephalomyelitis)?
Young adults, toy and terrier breeds
100
What are the 3 forms of GME (granulomatous meningoencephalomyelitis)?
- Disseminated: multifocal signs involving forebrain, cerebellum, brainstem, spinal cord
- Focal
- Ocular: acute onset visual impairment, papillary changes, optic disc oedema
101
Which dog breeds are prone to NE (necrotising meningoencephalitis and leucoencephalitis)?
Toy breeds eg pugs, maltese, chihuahua, pekinese
102
How do you treat MUOs?
-Immunosuppression: corticosteroids, cytosine arabinoside, cyclosporin, lomustine
103
Neurological signs associated with FIP are usually localised to which brain region?
Cerebellomedullary
104
Give some neurological clinical signs that can be associated with FIP
Tetraparesis, ataxia, nystagmus, loss of balance, sometimes behavioural changes or seizures +/- iritis/anterior uveitis/chorioretinitis
105
Which cranial nerves pass by the middle ear?
- CNVII (facial)
| - CNVIII (vestibulocochlear)
106
Give some clinical signs of otitis media/interna
- Pain opening the mouth
- Horners syndrome
- Facial paralysis
107
Give some examples of ototoxic drugs
- Antibiotics (aminoglycosides, tetracyclines)
- Chemotherapy agents (vincristine, cisplatin)
- Chlorhexidine -> perforated ear drum
108
What is the only thing you should lavage the middle ear with?
Warm saline
109
How can you investigate peripheral vestibular disease?
- Examine ear canal
- If tympanic membrane broken -> swabs, C&S
- Myringotomy if indicated (small hole in tympanic membrane)
- Lavage if indicated (warm saline)
- MRI/CT
110
How can you investigate central vestibular disease?
- MRI
- CSF analysis
- Blood pressure/urine analysis/caogulation profile
- Abdominal US/thoracic radiographs
- Serology for infectious diseases
111
What is the difference between sensorineural and conductive deafness?
- Sensorineural: failure to conduct sound from cochlea to auditory cortex of brain
- Conductive: failure to conduct sound from outer ear to inner ear
112
Which dogs and cats are affected by sensorineural deafness?
Breeds with white pigmentation and blue eyes eg dalmation
113
How can you assess hearing in dalmation puppies?
- BAER test (brainstem auditory evoked response)
| - Done at 8 weeks old
114
Which cranial nerve does a BAER test assess?
Vestibulocochlear
115
Which nerve plexus supplies the HLs?
L4-S1
116
Which nerve plexus supplies the FLs?
C6-T2
117
Which nerve plexus supplies the neck?
C1-C5
118
What is discospondylitis?
Infection and inflammation of intervertebral disc and adjacent vertebrae
119
Give the clinical signs of discospondylitis
Significant spinal pain, may have systemic signs of illness
120
Discospondylitis is most likely to occur where along the spinal cord?
L7-S1
121
Discospondylitis is most commonly caused by which infectious agent?
Staph intermedius
122
How do you diagnose discospondylitis?
- Imaging: radiographs, MRI or CT (narrowing of IVD space, roughening of endplates, proliferation of adjacent bone)
- Bacteriology: blood, urine, CSF
123
How do you treat discospondylitis?
- Long-term antibiotics (based on sensitivity)
| - NSAIDs initially when painful
124
What is chiari-like malformation?
- Malformation of the skull- cerebellum protrudes through foramen magnum
- CKCS
125
How do ischaemic myelopathies usually occur?
- Fibrocartilage from nucleus pulposus embolises in spinal cardvasculature- fibrocartilagenous embolism
- Hypertension in cats
126
Which dog breed is more affected by ischaemic myelopathies?
Miniature schnauzer
127
How do you diagnose an ischaemic myelopathy?
MRI
128
How do you treat an ischaemic myelopathy?
- Supportive care, physio
| - Usually takes 10 days to walk again (max. 3-4 months)
129
What is SRMA?
- Steroid-responsive meningitis-arteritis
| - Immune-mediated inflammation of the blood vessels in the meninges lining the spine
130
What are the clinical signs of SRMA?
- Spinal pain, pyrexia, lethargy
| - Occasionally neurological deficits
131
Which dog breeds are more affected by SRMA?
- Boxers, Beagles
| - 6-18 months old
132
How do you treat SRMA?
-Corticosteroids for 4-6 months +/- other immunosuppressive drugs (azathioprine)
133
How do you diagnose SRMA?
- Leucocytosis with neutrophilia
- CSF analysis: increased neutrophils and protein
- Increased IgA in CSF and serum
134
Atlanto-axial (AA) instability occurs in which dog breeds?
| Why?
- Young dogs, toy breeds
| - Failure of ligamentous support between the two vertebrae, usually asociated with aplasia/hypoplasia of the dens
135
Give some clinical signs of atlanto-axial intability
- Neck pain
| - Ataxia or tetraplegia
136
How do you treat atlanto-axial instability?
- Conservative splint for 6-12 weeks
| - Surgery
137
Give some clinical signs of chiari-like malformation
- Neck pain
- Neck scratching
- Torticollis/scoliosis
- Thoracic limb weakness and atrophy
138
How do you treat chiari-like malformation?
- Medical: NSAIDs, furosemide, gabapentin, corticosteroids, amantadine
- Surgery
139
What is the difference between Hansens type I and II IVDD (intervertebral disc disease)?
- Type I: herniation of nucleus pulposus through annular fibres and extrusion into the spinal canal (chondrodystrophic breeds)
- Type II: annular protrusion but no extrusion of nuclear material (large breed dogs)
140
Intervertebral disc disease typically affects which vertebrae?
T12-L2
141
How would you diagnose IVDD?
- Radiography: narrowed IVD space (spondylosis with type II)
- Myelography
- CT, MRI
142
How would you treat IVDD?
- Conservative: strict rest for 6-8 weeks for type I, 4-6 weeks for type II, NSAIDs
- Surgical: if neurological deficits/ severe or recurrent pain
143
Give some clinical signs of cervical spondylomyopathy ('Wobbly dog')
- Large breeds and Basset hounds
- Progressive ataxia, tetraparesis, sometimes pain
- Signs worse in the pelvic limbs (paresis, ataxia)
- Short stilted gait and muscle atrophy in thoracic limbs
144
What might hyperviscosity of blood indicate?
Polycytaemia
145
What might inclusion bodies indicate on a haematology?
Lysosomal storage disease
146
What is the gold standard diagnostic tool for the acquired form of Myasthenia Gravis?
Acetylcholine receptor antibodies titres
147
What is the gold standard diagnostic tool for masticatory muscle myositis?
Type 2M antibody titres
148
Seizures occur due to a change in activity where?
Forebrain
149
Give some deficits associated with a forebrain lesion
Seizures
Circling
Behaviour change
Head turn (to side of lesion)
150
Give the 4 stages of a seizure
1. Prodrome (any predicting events)
2. Aura (initial manifestation of seizure)
3. Ictal (seizure event- involuntary muscle tone or movement +/- abnormal sensations or behaviour)
4. Post-ictal (can have unusual behaviour or neurological deficits for minutes to days after)
151
How long does the ictal stage of a seizure normally last?
60-90 seconds
| Occurs most commonly at sleep or rest
152
What are the 2 major categories of seizure?
Generalised (involvement of both cerebral hemispheres simultaneously; consciousness is impaired)
Focal (activation of one part of one cerebral hemisphere)
153
What are the phases of a generalised seizure?
Tonic-clonic (most common)
Tonic (conraction of all skeletal muscles, legs out, head back)
Clonic (rhythmic movements eg jerking, clamping jaw, paddling of legs)
Myoclonic (sudden jerking motions
Atonic (sudden and general loss of muscle tone -> collapse)
154
What are the forms of a focal seizure?
Motor
Autonomic
Behavioural
155
What are audiogenic reflex seizures?
Cats, late onset (15yrs)
| Myoclonic seizures caused by high-pitched sounds (can progress to tonic-clonic)
156
How do you control audiogenic reflex seizures?
Levetiracetam
157
What are the criteria for a diagnosis of idiopathic epilepsy?
2 or more seizures (24 hours apart)
Age of onset 6m to 6y
Unremarkable inter-ictal examination (period between seizures)
No clinically significant abnormalities on minimum database (haem/biochem/fasting bile acids/urinalysis)
Unremarkable MRI and CSF analysis
158
When should you start treatment for epilepsy?
Structural/metabolic epilepsy
Status elipticus or cluster seizures
6 months or less between seizures
Post-ictal signs are severe or last longer than 24 hours
Seizure frequency and/or duration is increasing
1st seizure is within 1 month of a traumatic event
159
Are any seizure medications licensed in cats?
No
160
Which are the 3 licensed seizure medications?
Phenobarbitone
Bromide (Potassium or sodium bromide salts)
Imepitoin
161
What is the mechanism of action of phenobarbitone?
Enhances GABA (inhibitory neurotransmitter of CNS)
162
What are the initial doses for phenobarbitone in cats and dogs?
Dogs: 3mg/kg BID
Cats: 2mg/kg BID
163
Give some side effects of phenobarbitone
Sedation, ataxia
PUPD, polyphagia
Hepatotoxicity
Haematological abnormalities (anaemia, neutropenia, thrombocytopenia)
164
When is phenobarbitone contra-indicated?
Dogs with hepatic dysfunction
165
What is the mechanism of action of bromide (anti-seizure medication)?
Raises the seizure threshold by inhibiting transport of Na+
166
What are the initial doses for bromide in cats and dogs?
Dogs: 30mg/kg SID
| DON'T USE IN CATS
167
Give some side effects of bromide
Sedation
| Ataxia and HL weakness
168
What is the dose for imepitoin in dogs?
10-30mg/kg BID
169
What is status elipticus?
Seizure lasting >5 mins, or >2 seizures without full recovery
Emergency
170
What are cluster seizures?
2 or more seizures within 24 hours
| Emergency
171
Give some causes of status elipticus seizures in dogs
```
Neoplasia
CNS inflammatory disease
Trauma
Metabolic disorders
Toxicities
Idiopathic epilepsy
```
172
Why are status elipticus and cluster seizures an emergency?
Stage 1: increased autonomic activity (tachycardia, hypertension, hyperglycaemia)
Stage 2: irreversible neuronal damage (after 30 mins; hypotension, hypoglycaemia, hyperthermia, hypoxia, brain damage)
173
How do you stop a seizure?
Diazepam 1mg/kg per rectum
174
What is meant by 'breakthrough seizures'?
When an epileptic dog is medicated and still has seizures, we call them “breakthrough seizures”
175
How would you begin medicating a dog that is experiencing cluster seizures/status elipticus?
Place iv catheter
Phenobarbital 3mg/kg BID
If seizures don't stop/there are further seizures over the next 1-3 hours: phenobarbital iv loading (boluses)
If further seizures: levetiracetam loading
176
Give a side effect of using potassium bromide as an anti-seizure medication in cats
Eosinophilic bronchitis
177
Give a side effect of using diazepam as an anti-seizure medication in cats
Hepatic necrosis (oral administration)
178
Give some differentials for acute onset non-ambulatory tetraparesis
Neuropathy: polyradiculoneuritis
Junctionopathy: myasthenia gravis, botulism, organophosphate toxicity
Myopathy: severe polymyositis, electrolyte abnormalities eg Addisons
179
Which markers do we use for acquired myasthenia gravis?
Acetylcholine receptor antibodies
180
Which markers do we use for masticatory myositis?
2M antibodies
181
What is polyradiculoneuritis?
Inflammation of nerve and roots
| Fairly common
182
Give some causes of polyradiculoneuritis
Idiopathic/rabies vaccine, immune-mediated?
Breed predisposition in Bengal cats
Demyelination
183
Give some clinical signs of polyradiculoneuritis
Acute onset, rapidly progressive (days)
Tetra/paraparesis -> non-ambulatory tetraparesis/plegia
Flaccid, reduced motor fuction (inc absent reflexes)
Can affect respiratory muscles
184
How do you diagnose polyradiculoneuritis?
Electrophysiology (f waves will be lost/delayed) and CSF analysis (lumbar)
185
How do you treat polyradiculoneuritis?
Supportive: nursing, physio, ventilatory support if necessary
Fair prognosis
186
What is myasthenia gravis?
Muscle weakness due to reduced neuromuscular transmission
187
What causes the 2 forms of myasthenia gravis?
Acquired: immune-mediated; Ab-mediated destruction of acetylcholine receptors
Congenital: deficiency of acetylcholine receptors
188
>80% of dogs with myasthenia gravis also have what?
Megaoesophagus (only 15% in cats)
189
Which cat breed is predisposed to myasthenia gravis?
Abysinnian
190
25% of cats with myasthenia gravis also have what?
Thymoma
191
How do you treat myasthenia gravis?
Anti-cholinesterase (pyridostigmine po)
Immunosuppression?
Postural feeding if mega-oesophagus
192
What is meant by the 'fulminant' form of myasthenia gravis?
Sudden onset of megaesophagus and frequent regurgitation of large volumes of fluid
193
How does botulism affect nerves?
Toxins prevent acetylchline release at nerve junctions
194
Give some clinical signs of botulism
Acute onset rapidly-progressing tetraparesis
Cranial nerves may be affected: facial paralysis, megaoesophagus, altered jaw tone
Respiratory muscles may be affected
Urinary dysfunction, GI dysmotility, mydriasis, reduced tear production
195
How do you treat botulism?
Supportive care
| Physiotherapy
196
Give some clinical signs of immune-mediated polymyositis
Exercise intolerance, generalised weakness, muscle atrophy
| Pyrexia, stiffness, non-ambulatory tetraparesis, reluctance to move, lowered head carriage, myalgia (muscle pain)
197
How do you diagnose immune-mediated polymyositis?
Inflammatory leucogram, elevated CK/AST
| Muscle biopsies
198
How do you treat immune-mediated polymyositis?
Prednisolome +/- other immunosuppressives
199
Are cats or dogs affeced by masticatory myositis?
Dogs only
200
Why does masticatory myositis occur?
Antibodies to 2M myosin -> myositis
201
Give some clinical signs of acute and chroninc masticatory myositis
Acute: swollen/painful masticatory muscles, exophthalmos
Chronic: trismus (pain/fibrosis), mastictory muscle atrophy
202
How do you diagnose mastictory myositis?
Imaging
CK (may be slightly elevated)
2M antibodies
203
How do you treat masticatory myositis?
Prednisolone +/- other immunosuppressive drugs
| Physio
204
What is the most likely cause of an infectious myositis?
Protozoa eg Toxoplasma, Neospora
205
Give some clinical signs of Neosporosis in puppies
Radiculoneuritis and polymyositis
Pelvic limb hyperextension
Ascending paralysis of pelvic limbs with muscle contracture and arthrogryposis
206
How do you diagnose Neosporosis in puppies?
Clinical signs, biopsy, CK/AST. serology
207
How do you treat Neosporosis in puppies?
Clindamycin/TMPS and pyrimethamine
208
What is neuropraxia?
Temporary nerve damage but no disruption of the nerve or myelin sheath
Good prognosis, will return to normal function in a few days
209
What is axonotmesis?
Disruption of the axon but intact myelin sheath
| Good prognosis but slow recovery
210
What is neurotmesis?
Partial/complete transection of the nerve
| Partial recovery is possible
211
Give some clinical signs of brachial plexus avulsion
Monoparesis, cutaneous trunci absent ipsilaterally, Horner's syndrome
212
Give some clinical signs of a brachial plexus tumour?
Malignant peripheral nerve sheath tumour
Chronic progressive thoracic limb lameness, pain, muscle atrophy
Neurological deficits
213
How do you diagnose a brachial plexus tumour?
Electrodiagnostics
| Imaging (MRI best)
214
How do you treat a brachial plexus tumour?
Surgery
215
How do you differentiate central from peripheral vestibular disease?
Central: may have paresis and prorioceptive deficits, nystagmus may be vertical, horizontal or rotatory
Peripheral: may have Horner's syndrome, nystagmus may be horizontal or rotatory
216
Give some causes of acute onset vestibular disease
Idiopathic vestibular dz
Cerebrovascular dz
Head trauma
Trauma to middle/inner ear
217
Give some causes of chronic onset vestibular disease
```
Otitis media/interna
Brain and middle ear tumours
Thiamine deficiency
Lysosomal storage dz
MUO, FIP
Degenerative dz
Brain malformation
Congenital vestibular dz
```
218
Give some causes of vestibular disease that can be acute or chronic onset
Metronidazole toxicity
Ototoxic drugs
Hypothyroidism
219
How do you diagnose MUOs?
MRI
220
How do you diagnose FIP in cats?
Clinical signs
Lymphopenia, neutrophilia, non-regenerative anaemia
Increased serum alpha-1-acid glycoprotein
High serum titres of feline coronavirus Ab
MRI: ventricular dilation
221
Give some signs of metronidazole toxicity
| When does it occur?
Seizures, tremors, rigidity, hypermetria
| Usually when doses are >60mg/kg/day
222
How do you treat metronidazole toxicity?
Discontinue drug
| Give diazepam
223
Give some clinical signs of a thiamine deficiency
Bilateral central vestibular signs, seizures
224
Give some clinical signs of bilateral vestibular disease
Crouching low to the ground
May fall to both sides
Wide lateral excursions of the head
225
What age of dogs are affected by idiopathic vestibular disease?
Adult to geriatric
226
How do you treat idiopathic vestibular disease?
No tx needed-will resolve spontaneously
227
How do you diagnose idiopathic vestibular disease in dogs?
Diagnosis of exclusion
228
What are the 2 forms of feline idiopathic vestibular disease?
Acute onset, non-progressive, improves over 2-4 weeks
Atypical form: acute onset but clinical signs progress over 3 weeks; recover after 3 months but milk residual head tilt may remain
229
How do ischaemic myelopathies occur?
Fibrocartilage from nucleus pulposus embolises in the spinal cord vasculature -> fibrocartilagenous embolism -> blocks off blood supply to part of spinal cord
230
When do clinical signs of ischaemic myelopathies occur?
| What signs do you see?
Exercise
| Vary from mild weakness or incoordination, to inability to walk
231
What is chiari-like malformation?
Mismatch between caudal fossa volume and its contents, with caudal displacement of the cerebellum through foramen magnum
Can develop syringomyelia (fluid-filled 'cyst' in spinal cord)
232
How do you diagnose cervical spondylomyelopathy?
Myelography +/- CT, MRI
233
How do you treat cervical spondylomyelopathy?
Anti-inflammatories, rest
| Surgery
234
What is 'cauda equina' syndrome?
Degenerative lumbosacral stenosis
Arthritis of the joint between the last lumbar vertebra and the sacrum -> narrowing of spinal canal -> pressure on nerves coming off spinal cord
235
Give some clinical signs of 'cauda equina' syndrome?
Reluctance to exercise, rise, jump into car, do stairs
Proprioceptive deficits, reduced withdrawal reflex, muscle atrophy
Lameness
Lumbosacral/hip pain
Mono/paraparesis
Urinary and/or faecal incontinence
236
How do you treat cauda equina syndrome?
Conservative: rest and NSAIDs
Surgery: dorsal laminectomy/ dorsal fusion-fixation/ foraminotomy
237
Give some clinical signs of degenerative myelopathy
Insidious, progressive ataxia and paresis of pelvic limbs -> paralysis
Not painful
Age of onset: 5-9y
238
Are there any treatment options for degenerative myelopathy?
No therapeutical options
| Physio
239
How do you perform a hemilaminectomy?
Remove one half of the vertebral arch (lamina, articular process and pedicle) and expose spinal cord -> remove ruptured disc material
Used to correct slipped or herniated discs in the thoracolumbar spine
240
How do you perform a dorsal laminectomy?
Remove dorsal spinous process and laminae -> access to spinal cord
241
Which drug can you give to dogs with canine cognitive dysfunction?
Selegiline
242
Give some clinical signs of canine cognitive dysfunction?
Disturbances in sleeping; pacing/vocalising at night
Getting stuck in corners, staring into space
Loss of house-training ability
New behavioural problems
243
What is myelography?
Injection of positive contrast into subarachnoid space
244
Where should you inject when doing a myelography?
```
Cistern puncture (easier)
Lumbar puncture (safer, more difficult)
```
