Deck 13 Flashcards
(100 cards)
1
Q
Pituitary apoplexy can be either due to ___________ or __________.
A
Hemorrhage or infarction
2
Q
What were the two most common presenting clinical signs in this paper?
A
Altered mentation and gastrointestinal disturbances
3
Q
What percentage of these dogs survived? Was there any parameter that predicted survival?
A
Approximately 60% survived.
Survivors had a median MGSC score of 16 compared to non-survivors with a score of 15…
Additionally animals that received mannitol were less likely to survive.
4
Q
Of the animals that survived to discharge, what therapy helped significantly extend survival following discharge?
A
Radiation therapy (973 days v 143 days)
5
Q
What stage of hemorrhage is this?
A
The bulk of it is relatively hypointense on T2 and iso to slightly hypointense on T1. Thus, this is most consistent with acute hemorrhage (I Die).
6
Q
True or false — in one publication regarding listerial encephalitis in goats, male goats were more likely to die, and circling was associated with better prognosis
A
True
7
Q
What is the genetic defect associated with myotonia congenita in Miniature Schnauzers?
Pseudomyotonia in the English Cocker / Springer Spaniels
A
CLCN1
SCL7A10
8
Q
In what breed / species was photic stimulation used to induce SEDs? Success rate with stimulation?
A
Arabians with juvenile epilepsy
7/10 epileptic horses showed SEDs while none of the controls did
9
Q
True or false — the EDX findings of pseudomyotonia in Springer Spaniels / English Cockers are show the classic fibrillation potential, positive sharp waves and CRDs.
A
False — they are normal.
10
Q
What type of hypercortsolism is implicated in severe muscle stiffness? Do signs of hypercortisolism precede muscle stiffness in all cases?
A
In one retrospective study, PDH was the only type of hypercortisolism to be associated with severe muscle stiffness, and in about 1/3 of cases, muscle stiffness was the first sign!
11
Q
Identify what type of spontaneous muscle activity is occurring in each of these?
A
A — myotonic discharge (has waxing and waning)
B — complex repetitive discharges
C — fibrillation potentials
D — positive sharp waves
All of these were identified in dogs with PDH.
12
Q
Which muscles were most affected in dogs with severe muscle stiffness associated with hypercortisolism?
Which limbs are predominantly affected at presentation? Can this progress?
A
Proximal limbs and epaxial musculature.
Primarily pelvic limbs were affected, but this can progress to the thoracic limbs or even to the masticatory muscles.
13
Q
True or false — prophylactic administration of omeprazole in dogs with TL disc herniations helps reduce the incidence of GI signs
A
False — no difference was seen in a double blinded placebo controlled clinical trial
14
Q
For diagnosis of spinal cord dysfunction in horses: rate from most to least accurate
Neuro exam
Cervical rads
Transcranial magnetic stimulation with recording of magnetic motor evoked potentials
A
TMMEPs > neuro exam > rads
15
Q
What percentage of normal pug dogs have CAPD?
A
97%
16
Q
What is this picture demonstrating?
A
Arachnoid thickening / fibrosis in a Pug dog with a constrictive myelopathy
17
Q
What were the themes identified in this publication?
A
- all pug dogs had CAPD
- majority of pug dogs had multiple causes of their myelopathy (CM and ‘IVDH’ most common)
- majority of pug dogs had multiple areas of SC compression present
18
Q
What type of cervical spinal cord disease is most commonly associated with Horner syndrome?
A
Non-compressive / intraparenchymal disease, mostly commonly FCEM. The presence of intraparenchymal intensity changes correlated with Horners.
19
Q
For how long after the addition of autologous serum to CSF samples, are TNCC, cell morphology and protein stable?
A
At least 96 hours (studied in horses)
20
Q
What is more sensitive for detection of bacterial meningitis — CSF cytology or CSF culture?
A
CSF cytology
21
Q
What was the average duration of antibiotic treatment? How did this change between medically and surgically managed cases?
A
8 weeks on average in all cases
Medically managed — 9 weeks
Surgically managed — 3 weeks
22
Q
What are some dog breeds that have been shown to have a congenital insensitivity to pain? What is the genetic defect / the structure altered?
A
Border Collies, Spaniels and Pointers (and mixed breed dogs)
SCN9A — voltage gated sodium channel
23
Q
What was the difference in survival/PFI between shunted and non-shunted cases?
A
Shunted cases — 1103 days / 895 days
Non-shunted cases — 162 days / 71 days
24
Q
What MRI features can be used to discriminate between high and low grade oligodendrogliomas?
A
All high grades had strong, ring CE, while none of the low grades did. High grades also had more cystic structures, GRE signal voids and necrosis.
25
What is the distinction between idiopathic epilepsy and epilepsy of unknown cause?
It’s the age range. EUC involves dogs either younger than 6 months or older than 6 years.
26
What type of seizures do Pomeranians with epilepsy get? What are some helpful ways to distinguish this from a movement disorder?
- they get focal motor seizures characterized by limb flexion / stiffness
- EEG often shows interictal spikes, and the dogs often have good responses to anti-convulsants (zonisamide most common).
- Additionally some of these dogs had autonomic signs (urination, defecation, mydriasis and salivation)
27
What is a unique clinical sign of forebrain disease involving the mouth? What particular location was often affected?
Awake bruxism
Thalamus / diencephalon
28
Expected F wave latency for thoracic and pelvic limbs
Expected ulnar nerve F wave latency (s)
6.03 + 0.22 x limb length (cm)
Expected tibial nerve F wave latency (s)
3.45 + 0.33 x limb length (cm)
29
What type of neuropathies will always cause EMG changes? Which ones will not?
Motor neuropathies will always cause EMG changes unless they are specifically demyelinating. Pure sensory neuropathies will also not cause EMG changes.
30
Where should the reference (aka ground) electrode be placed during EMG?
Over a bony prominence ideally
31
What are two ways that we can distinguish motor unit action potentials from fibrillation potentials?
1. Amplitude and duration — MUAPs typically have a higher amplitude (100-3000mV) and longer durations (up to 12 ms) compared to fibrillation potentials (amp 20-500mV, duration 1-5ms)
2. Fibrillation potentials (pictured) will classically have a large positive (down) deflection first, followed by a large negative deflection while MUAPs have a small positive deflection followed by a large negative deflection.
32
Giant MUAPs are indicative of what?
Re-innervation of previously denervated myofibers
33
How can we distinguish between end-plate spikes and fibrillation potentials?
End-plates spikes are only ever biphasic, with an initial negative deflection, while most fibrillation potentials will be triphasic with a relatively large positive deflection first.
Occasionally, fibrillation potentials can be biphasic, and look identical to end-plate spikes. To differenaite them, remember that end-plate spikes are often accompanied by MEPPs, and that end-plate spikes will disappear if you move your recording electrode to somewhere else.
34
What type of spontaneous muscle activity occurs when the generator is the following:
- motor neuron / axon
- individual muscle fibers
- multiple muscle fibers
35
Why do muscles become more active in the case of denervation / muscle damage?
Increased number of acetylcholine receptors
36
What were the most frequently encountered CT findings of discospondylitis?
End plate erosion / osteolysis
Periosteal proliferation / reaction
Vertebral body (involving 1/3 of the body with lysis)
37
True or false — short-term outcomes in camelids with neurologic disease is correlated with CSF TNCCs.
True — a CSF TNCC <3 is associated with improved survival outcomes
38
Is trazodone “safe” to give to dogs before neurologic evaluation?
Technically no — it caused new or progressive postural reaction deficits in 22% of dogs in one study.
39
What are the CT angiography findings of epidural AVM?
What was the treatment provided to three cats with this malformation?
Dilation / contrast enhancement of the venous structures (interarcuate branches, vertebral plexus, azygos vein) during the arterial phase.
Dorsal laminectomy with ligation of interarcuate branches
40
The length of what bone is important in calculating the distance for the 50-step walking test?
Average time for non-DPN dogs to walk? DPN dogs?
What was one additional factor aside from neurologic status that was associated with outcome?
Ulna
14 days v 90 days
Pre-surgical anesthetic times — but this was likely artifactual as more non- DPN dogs had pre-op CTs compared to more DPN-dogs having MRIs.
41
What were some of the main findings in this article?
No influence of CRI type on recovery of ambulation / post-op pain scores
+/- more intra-operative bleeding in the ketamine / dexmed group
Mild improvements in time to eating / urination in the ketamine / dexmed group.
42
Describe a ratio that can be measured on a CBC that can be used to help increase the suspicion of dogs with MUE.
What type of disease was not evaluated in this study?
The neutrophil to lymphocyte ratio — this ratio was higher in dogs with MUE (~6). Sensitivity and specificity were decent (70 and 90%).
However, no dogs with infectious meningoencephalitis were evaluated, which is often the main ddx for MUE.
43
Did an 11% boost to the total radiation dose improves outcomes for brain tumors?
No
44
What is the abnormal genetics associated with NME?
Linked to chromosome 12, specifically the dog leukocyte antigen MHC II complex
45
What were the most reproducible clinical signs in Pug dogs with the early NME phenotype? How did this correlate with genetic risk? Where did MRIs show abnormalities?
Spinal pain (neck and TL). Less commonly, menace response deficits and postural reaction deficits were present as well.
These signs were only seen in dogs with high genetic risk profiles (homozygous or heterozygous for the chromosome 12 DLA MHC II abnormality).
MRI abnormalities were predominantly in the parietal and occipital lobes (corresponding to visual and proprioceptive deficits).
46
What were some of the major findings of this study?
- epidural hemorrhage was more common in Frenchies
- epidural hemorrhage cases had a more rapid onset of signs / non-ambulatory status
- epidural hemorrhage cases had less spinal cord compression but more intramedullary signal change
- epidural hemorrhage was associated with worse outcomes at 4 weeks
47
What MRI sequences are the best at delineating “surgical margins” for the following tumor types:
- meningioma
- histiocytic sarcoma
- glioma
Meningioma — T1 + C
Histiocytic — T1 + C
Glioma — T2 (with FLAIR images a close second)
48
Describe the relationship between hydromyelia and focal disc herniations. Where along the spinal cord was the hydromyelia more prominent?
Hydromyelia was more common in acute stages, and absent in chronic stages of IVDH. It was more often located cranial to the disc herniation.
49
Describe the myoclonus of CKCSs.
- older dogs (>8 yo)
- involves rapid blinking, head nodding and thoracic limb movements
- responds decently to levetiracetam
50
Using specialized sequences, detection of what correlated with seizures in dogs with MUE?
MRI evidence of blood brain barrier dysfunction correlated with seizures
51
Did the use of pre-operative anti-convulsants decrease the risk of early post-operative seizures?
When did all early post-operative seizures start?
What was the significance of early post-operative seizures?
No
24 hours
Prolonged hospitalization, more complications and less likely to survive to discharge
52
True or false — CNS lymphoma typically affects one intracranial or spinal compartment.
What other features are commonly identified on MRI?
False — CNS lymphoma often affects both extra and intraparenchymal compartments in the brain, and multiple spinal cord compartments
Contrast enhancement and extra-CNS involvement
53
Neurolymphomatosis in cats has a predilection for what site?
Lumbosacral
54
In this publication, what percent of cases had lymphoma diagnosed via CSF cytology?
20%
55
What is the impact of pre-appointment gabapentin on feline neurologic examination?
Why do older cats have this happen?
Why does this happen?
50% of cats developed new / worsening neurologic deficits. These were more marked in older cats.
Older cats have more CKD, and gabapentin is cleared by the kidneys.
Presumably gabapentin’s effects on the cortical neurons.
56
Of dogs with status epilepticus, for how many was this their first seizure manifestation?
43.5%
57
In this publication, what were some risk factors associated with not surviving to discharge?
Risk factors for SE recurrence?
Survival
- Increasing age
- Presenting in SE (as opposed to having it develop in hospital)
- A likely fatal underlying etiology
- shorter duration of hospitalization
Recurrence
- history of drug resistance
- focal seizures
58
How can you distinguish between nerve root avulsion, neurotmesis, axonotmesis and neuropraxia on electrodiagnostics?
Nerve root avulsion — absent CMAPs, but present SNAPs (with avulsion, the cell body of the sensory neurons is still connected to its axons, so no Wallerian degeneration occurs in the sensory fibers in that part of the nerve)
Neuronotmesis — no CMAPs or SNAPs
Axonotmesis — reduced CMAPs and SNAPs
Neuropraxia — normal CMAPs and SNAPs, no abnormal EMG activity either
59
In this study, what was the EDX parameter that was most specific for recovery of limb function?
When was EDX testing performed in this study?
What type of nerve injury was occasionally misdiagnosed?
- A radial nerve CMAP obtained in the extensor carpi radialis muscle above 5 mV was 93% specific for recovery — it was poorly sensitive at this cutoff though, and even animals with a value less than 5 could recover
- at least 7 days after trauma
- some animals that we diagnosed with neurotmesis actually had nerve root avulsion (absent SNAPs were sometimes misleading).
60
What are two mutations associated with Lafora disease, and what are the proteins they code for? What is the underlying gene?
EPM2A — laforin
EPM2B — malin
The underlying gene is NHLRC1
61
What are the most common clinical signs in Beagles with Lafora disease?
Did this impact their overall lifespan?
Myoclonic seizures (all), generalized tonic-clonic seizures (most), coordination difficulties, visual and hearing deficits, and a variety of behavioral changes.
Minimal impact on overall lifespan.
62
What was the most common side effect of implantable VNSs in dogs?
Coughing
63
Describe the utility of monitoring serum phosphorylated neurofilament heavy chain in a post-op disc herniation dog.
Serum pNF-H levels were significantly elevated starting at 24 hours post-op in dogs that developed myelomalacia, and they continued to increase within the following 48 hours.
These levels were NOT associated any other outcome (ie ability to walk or not in the other dogs evaluated).
64
This postural abnormality can uncommonly develop in cases of immune-mediated meningomyelitis.
Cervical scoliosis
65
True or false — orthostatic tremor is characterized as an action-related postural tremor
True — it is action related because the muscle are actively resisting the effects of gravity
66
What are the four features used to diagnose an orthostatic tremor?
- high frequency visible / palpable limb tremor (>12 Hz)
- absence of tremors during non-weight bearing postures / walking
- helicopter sign
- tremor reduction on weight-bearing lifting test
67
What are some clinical signs associated with orthostatic tremors? Do they progress?
Difficulty rising and sitting down, “dancing” sign (alternating weight between limbs), wide-based stance/gait, difficulty maintaining posture, and rarely falling.
Often they do progress
68
What were three medications in this article that had good success treating the tremors? Which one was the most effective? Was improvement complete or partial in most cases?
Phenobarbital, gabapentin / pregabalin, and clonezapam
Phenobarbital (reportedly 100% effective)
Partial
69
What was unique about Retriever breeds in this paper?
They were older than the other dogs affected (3.5 yo v 2 yo), and were less likely to respond to treatment (~50%)
70
True or false — concurrent neurologic conditions can contribute to the development of an orthostatic tremor.
True — typically these dogs will be smaller, older and have concurrent neurologic signs
71
What is a clinical sign of dysautonomia that is unable to be explained by autonomic nervous system dysfunction? What is the explanation for this sign?
Decreased anal tone — there is mild involvement of the ventral grey matter and DRG in dysautonomia cases.
72
Define trismus.
Increased jaw tone
73
What is the most common **neuropathic** manifestation of FeLV in cats? What other manifestation can occur?
- mydriasis and concurrent anisocoria
- generalized with tetraparesis
74
What histopathologic findings are expected in cases of ischemic neuropathy?
Demyelination and Wallerian degeneration, with the central most fascicles being the most affected
75
What are the two proposed mechanisms associated with feline diabetic neuropathy?
Do cats get more sensory or motor deficits?
What structure is affected mostly on histopathology?
- hyperglycemia leads to increased flux of the polyol pathway causing a decrease in myoinositol and modification of proteins by glycation
- vascular changes resulting in peripheral nerve oxidative stress
- motor > sensory
- myelin (splitting and ballooning, with resultant demyelination)
76
What type of LSD do Norwegian Forest cats get? This a deficiency of what?What body systems does it affect?
Glycogen storage disease IV
Deficiency of the glycogen branching enzyme alpha -1,4D-glucan
Skeletal muscle, heart, CNS
77
What drugs can be used to treat myotonia congenita? What is their MOA?
Sodium channel blockers like procainamide and mexiltine
78
What is fiber type grouping?
This is when grouping of the same fiber types (1 or 2) occurs, typically following reinnervation in cases of a neuropathy.
79
Great Danes have what type of inherited polyneuropathy? Clinical signs?
What other breed of dog develops a similar polyneuropathy?
They have a distal sensorimotor polyneuropathy.
Oddly, it is an acutely progressive disease that occurs over a few weeks with signs of paraparesis first, with a relatively classic sciatic limb gait. Eventually progresses to hyporeflexia.
Rottweilers
80
What type of muscular dystrophy is associated with concurrent demyelination?
Laminin alpha-2 deficient muscular dystrophy
Laminin contributes to basement membrane formation of many different tissue types, including the muscles and Schwann cells.
81
What is one of the classic histopathologic findings of progressive axonopathy of Boxers? The pathogenesis is presumed to be a defect of what?
Spheroids
Slow axonal transport
82
What is the nerve that is most affected in giant axonopathy of German Shepherds?
Tibial
83
____________ Dachshunds have a ___________ neuropathy. What EDX findings are common? What is unusual about their neuro exam findings? What type of nerve fibers are most affected?
Long-haired, sensory
Completely normal aside from inability to elicit SNAPs
They have reduced reflexes but normal muscle tone and strength
Large, myelinated fibers are predominantly affected.
84
In the Pointer dogs with “acral mutilation”, what are the main clinical signs and what nerve fibers are predominantly affected? Where is the classic location for histopathologic abnormalities?
Self-mutilation of paws is the only sign; the rest of their exam is normal.
The nociceptive fibers (small myelinated and unmyelinated)
Dorsolateral fasciculus of spinal cord
85
What species has been affected by hyperchylomicronemia?
What is this due to a deficiency of?
What are the neurologic signs that develop?
Cat
Deficient lipoprotein lipase
Neurologic signs develop due to the formation of xanthomata (lipid accumulations) within the nerves, particularly where they exit the intervertebral foramen, causing a compressive neuropathy. The most frequently affected nerves are radial, tibial and Horners.
86
What breed is affected by fucosidosis? What type of LSD is fucosidosis?
English springer spaniels
It is a glycoproteinosis.
87
What are the classic clinical signs / progression of fucosidosis?
- 4-6 months: anxiety, poor at being restrained
- 1 year: gait deficits, hyper-reflexia
- 2 year: absent menace, positional nystagmus
3 year: most are dead
88
Age of onset of globoid cell leukodystrophy? Two main clinical signs? What cells are primarily impacted? EDX findings?
3 months
Cerebellar signs and paraparesis
Oligodendrocytes and Schwann cells
Very slow MNCV / SNCV, minimal EMG changes — consistent with myelinopathy
89
Which LSD causes PAS-positive accumulations within the muscle and peripheral nerves?
When do animals start showing clinical signs? What are they and how do they progress?
Glycogenosis type IV
5 months of age, with progression from muscle tremors to tetraplegia in 3 months. Fever is also common.
90
Niemann-Pick disease is in what family of LSDs?
What type results in a neuropathy? What kind of neuropathy is this?
What type of animal commonly gets NP disease?
Sphingolipidoses (specifically myelinosis)
Type A — demyelinating
Cats
91
Which lysosomal storage disease results in palpable hepatomegaly in cats?
Is there liver dysfunction?
What are the neurologic signs associated with this disease?
Niemann-Pick disease, type C — a type of sphingolipidosis
No liver dysfunction
Signs are primarily cerebellar, starting around 8-12 weeks of age
92
What were some of the main results from this study?
- Diagnostic accuracy was only 75% in regards to lesion location
- Sensitivity was worst for IDEM lesions
- positive diagnostic calls for IDEM lesions was helpful, as were negative diagnostic calls for IM lesions
93
Asymptomatic Pugs that are determined to be either high or medium risk for developing NME had what alterations in their leukocyte / cytokine profiles?
Less CD4+ T cells, and more IL-10 compared to low risk Pugs
94
What is the most common sign of disseminated coccidiodomycosis in dogs?
Lameness secondary to osteomyelitis
95
What was the most common presenting clinical sign in these dogs?
What was the survival rate in dogs with long-term follow-up?
Seizures (~50%)
~80% long-term survival rate (significantly better than previous reports)
96
What is the diagnosis?
This is coccidiodomycosis granuloma. Signficant peri-lesional edema, with a T2 hypo, T1 iso, strongly contrast enhancing granuloma.
97
What is the main side effect of fluconazole, and what medications should we be cautious about administering concurrently with it?
Hepatotoxicity — it is a CYP450
inhibitor!
Phenobarbital and zonisamide
98
True or false — brain DTI showed evidence of abnormalities in dogs with DM.
False — no differences were noted between DM dogs and controls
99
Supplementation of what can help prevent equine NAD/EDM? When should it be supplemented?
Alpha-tocopherol — should be supplemented in the last trimester / first 2 years of life
100
How is the metabolism of alpha-tocopherol in horses different in those that develop eNAD/EDM?
Metabolism is increased, resulting in lower serum values, particularly in QHs.
