Neuro Flashcards
What does the diencephalon include?
Thalamus
Hypothalamus
What does the forebrain include?
Diencephalon
Cerebrum
Cerebral white matter tracts and the basal nuclei are involved in what?
Sensory and motor control.
Unilateral forebrain lesion can cause what type of limb deficits?
Contralateral due to crossing over nerves in the mibrain (pic)
Unilateral lesions in the pons and medulla will cause what type of limb deficit?
Ipsilateral
What cranial nerves extent from the pons and medulla?
3-12.
Where is the vestibular nuclei located?
Medulla
Flocculonodular lobe of the cerebellum
A decerebellate posture is seen in lesions where?
Rostral cerebellum
Signs of cerebellar disease?
Hypermetria
Intention tremors
Ataxia and wide based stance
Decerebellate posture.
In the spinal cord the gray matter contains what?
Interneurons and LMNs
The spinal cord give rise to a dorsal and ventral root. Which one is motor and which one is sensory?
Dorsal is sensory.
Ventral is motor.
Where is the cervical intumescenece?
C6-T2
Where is the lumbar intumescence?
L4-S3
Why do dogs with a cervical lesion have more pronounced UMN deficits in the rear limbs vs the forelimbs?
The rear limb tracts are more peripherally in the cord
What makes up the peripheral nerves?
12 CNs
36 pair spinal nerves
Explain the neuromuscular junction process?
Calcium dependent release of the neurotransmitter acetylcholine from the synaptic cleft
ACh diffuses across the synaptic cleft and binds to ACh muscle receptors
ACh is rapidedly removed by Acetylcholinesterase
Myasthenia gravis is what type of neuromuscular disorder?
Post synaptic
Reduction of the number of functional ACh receptors.
Presynatic neuromuscular disorders usually cause what clinical sign?
Flaccid tetraparesis
Decreased Spinal reflexes.
What are common clinical signs of muscle disorders?
Weakness
Stiff or stilted gait
Exercise intolerance
Where does the pelvic nerve originate from?
L5-L6
What does the pelvic nerve do during micturition?
Detects bladder fullness
Supplies PARAsympathetic innervation to the bladder - CAUSING DETRUSOR MUSCLE TO CONTRACT
What nerve controls the external urethral sphincter m allowing for conscious and reflex control?
Pudendal n.
The hypogastric n supplies what?
SYMPATHETIC tone causing detrusor muscle relaxation and contraction of the internal urethral sphicter.
What three nerves control micurition?
Pelvic - Parasympathetic
Pudendal - Somatic
Hypogastric - Sympathetic
Where does the hypogastric n arise from
Cranial to mid lumbar
What is a LMN bladder?
Injury to the sacral spinal cord (pelvic and pudendal n) causing a large, flaccid bladder that is easily expressed
What is an UMN bladder?
Spinal cord injury causing an enlarged bladder that is hard to express
What is reflex or automatic bladder?
5-10 days after acute UMN spinal cord injury, there might be reflex detrusor contraction causing spontaneous partial empyting.
What is detruser-urethral dyssynergia?
When there is a spinal lesion cranial to L5 causing diministed voluntary control and reflex hyperexcitability of the urethral sphincter. Causing involuntary contraction of the urtheral sphincter during detrusor contractions.
What is the difference between decerebrate and decerebellate rigidity?
Decerebrate - All four limbs are extended with an extended neck (MIDBRAIN LESION)
Decerebellate - Thoracic limbs are extended along with neck. Hips are flexed due to flexed iliopsoas. (ROSTRAL CEREBELLAR).
Patellar reflex contains what n?
Femoral nerve
Spinal nerve L4, L5, L^
Pelvic limb withdrawal contains what nerves?
Sensory - Sciatic n (tibia and peroneal on the lateral), Femoral (saphenous on the medial)
Motor - Sciatic n (tibia (flexion of the digits) and peroneal (flexion of the tarsus)).
What is the perineal reflex or bulbourethral reflex used to assess?
Pudendal n
S1-S3
Where does the lateral thoracic nerve come from and what does it do?
Lateral thoracic comes from C8-T1
What is in control of pupil constriction?
CN3 Occulomotor
Complete external ophthalmoplegia is usually caused by?
Cavernous sinus syndrome
What type of strabimus is caused by CN3 damage?
Ventrolateral strabimus
What type of strabimus is caused by CN4 damage?
Dorsolateral strabismus
What does CN5 (trigeminal n) innervate?
Sensory of the face, cornea, nasal septum, nasopharyngeal membrane, teeth and gingiva
Motor of the muscles of mastication.
Bilateral CN5 lesions cause?
Drop jaw and inability to close mouth.
CN7 innervates what?
Muscles of the face
Seory of the rostral two thirds of the tongue and palate
Lacrimal glands and mandibular and sublingual salivary glands
CN9 innervates what?
motor to the pharynx and palate
Sensory to the caudal third of the tongue and pharynx
Parasympathetic to the parotid and zygomatic salivary glands
Vagus innervates?
Motor and sensory to the larynx, pharynx and esophagus
How to test the parasympathetic portion of the vagus?
Push on the eyballs and see the bradycardia reflex
Differentials for peracute nerve dysfunction?
External trauma
Internal trauma (disc/fracture)
Hemorrhage
Infarct
Toxin
Differentials for subacute progressive nerve dysnfunction?
Infectious
Non-infectious
Rapidly growing tumors
Metabolic
Some toxins
SRMA commonly has elevated serum and CSF what?
IgA
Risk factors for seizures in a myelogram?
Dogs over 29kg
Cisternal myelography
Two or more injections of contrast.
What projections is the most benifical for describing where a lesion is on the myelogram?
Lateral… the VD says the same thing all the time.
What are the most commonly biopsied nerves?
Common peroneal nerve and the ulnar n.
Brainstem lesions commonly have these clinical signs?
Altered consciousness
CN deficity
UMN paresis
Ataxia
CP deficits
List some metabolic encephalopathies?
Hyperosmolality
Hepatic encephalopathy
Hypoglycemia
Uremia
Electrolyte distrubances.
CPs are usually what with cerebellar diseases?
Normal
Reasons for ischemic strokes/clots that may not be on your radar?
Septic foci (endocarditis)
Primary/metastatic neoplasia
Vasculitis
HW
Cardiac disease.
Hypothyrodism/DM/Cushings and hyperlipidemia
Hypertension
Most common infarct location in dogs? Cats?
Cerebellar/Forebrain - Dog
Forebrain/brainstem - Cat
Feline ischemic encephalopathy - what artery is most commonly affected?
Middle cerebral artery
Feline ischemic encephalopathy - what time of year and place is it most common?
Summer - NE USA and outdoors
What pathology besides edema is common with cuterebra migration?
Infarction
What percentage of congenital hydrocephalus do not have symptomes until 2 years of age?
30%
What dogs get lissencephaly?
Lhasa Apso
Wire Fox Terrier
Irish Setter
What is the most common non-infectious inflammatory brain disease in dogs?
Granulomatous meningoencephalitis (GME)
What is cerebellar abiotrophy?
Neurodegeneration of the cerebellum in young dog (2-12 months)
There is adult onset in some breeds.
What is a main differential for cerebellar abiotrophy?
Neosporosis due to atrophy of the cerebellum
What side effects are seen with KBr toxicity?
Dysphagia
Megaesophagus
Repetitive episodes of autonomic signs (vomiting, diarrhea, abdominal discomfort, repetitive swallowing, licking or eating grass) could be a sign of?
FOCAL AUTONOMIC SEIZURE DISORDER.
Sign of pheobarital responsive syndrome?
Drooling, reching, dysphagia, enlargement of the mandibular salivary glands with necrosis.
What percentage of dogs and cats have idiopathetic epilepsy?
25%-30% dogs
Rare in cats
What percentage of dogs and cats have intracranial causes?
35% - dogs
Most cats
What coomon toxins cause seizures?
Strychinine
Metaldehyde (slug/snail/rat posison)
Mycotoxins
Chlorinated hdrocarbons (insecticides)
Organophosphates/Carbamates (INsecticides)
Lead
Ethylene glycol
Scar tissue-related acquired epilepsy is seen as what on MRI?
Normal
What is pendular nystamus and who is it common in?
Oscillatory movement with no slow or fast phase
Siamese, Birman and himalayan cats due to congenital abnormalities
Physiologic nystagmus is controlled by what reflex?
Oculocephalic reflex
What signs are the most consistent with Central vestibular disease?
Vertical nystagmus
UMN limb deficits
What CNs can be affected if lesions are at the cerebellomedullary angle?
CN5, CN7 and CN8
What is paradoxical vestibular syndrome?
Where the lesion is in the caudal cerebellar peduncle or flocculonodular lobe of the cerebellum
Causes head tilt on the contral lateral side
CP deficits on the ipslateral side
What is the difference between geriatric canine vestibular disease and feline idiopathic vestibular syndrome?
Feline idiopathic happens at any age…mid-atlantic… summer time
Most common aural tumors?
SCC
Ceruminous gland adenoma/adenocarcinoma
sebaceous adenoma/adenocarcinoma
Lymphoma
CN8 = neurofibroma, neurofibrsarcoma.
Differentials for peripheral vestibular disease?
Otitis media
Old dog
Polyps
idiopathic
trauma
neoplastic
Aminoglycoside
Congenital (3 months or less)
Hypothyroidism.
Differentials for central vestibular disease?
Inflammatory
Neoplasia
CVA - spaniels are predisposed
Acute idiopathic attacks
Metronidazole.
Most common sign of meningitis?
Neck pain and fever
SRMA is commonly seen in what age of dogs?
6-18mo
SRMA may have what concurrent disease?
IMPA
SRMA commonly is associated with what breed?
Beagles
Bernese Moutain Dogs
Boxers
German Shorthaired Pointers
Nova Scotia Duck Tolling Retrievers
If not treated effectively and promptly dogs with SRMA can develop?
Spinal cord infarction and meningeal fibrosis
What are the three forms of GME?
Focal - Space occupying mass
Ocular - optic neuritis
Disseminated - multifocal lesions
GME commonly affects what type of dogs?
Young small dogs (2-6 yo)
NME (necrotizing meningoencephalitis) is common in what two breeds?
Pugs - Younger onset - FEMALES
Maltese
NME MRI findings are commonly what?
White matter lesions just lateral to the ventricles
Grey-white matter junction causing LOSS OF NORMAL SHARP DEMARCATION!!!
GME focal lesion is indistinguishable from what?
NEOPLASIA
GME commonly involves?
BOTH the gray and white matter
Clinically important MRI finding for meningoencephalitis?
Well defined, T2 hyperintense, T1 hypointense regions consistent with necrotizing areas
NLE is commonly associated with what breed?
Yorkies***
Frenchies
Caniine eosinophilic meningitis is commonly associated with what two etiologies?
Idiopathic
Fungal/protozoal/helminth
Caniine eosinophilic meningitis is commonly associated with what type of dog?
Young and large
What rickettsial diseases can cause meningoencephaltis?
E. canis
E. Ewingii
RMSF E. rickettsii
A. Phagocytophilum
Systemic neospora can cause?
fever
pneumonia
hepatitis
pancreatitis
Esophagitis
Pyogran dermatitis.
Neospora commonly affects very young dogs due to what?
Its predominant transplacental route of transmission
6wks- 6mon
Common MRI finding for neospora?
Cerebellar hypotrophy.
Can lyme’s disease cause encephalitis?
Yes
What fungus commonly infects only the CNS due to its predilection for the CNS of dogs and cats?
Cryptococcus
“Lil white shaker syndrome” aka?
Canine steroid responsive tremor syndrome
Westies and Maltese
Feline polioencephalitis is like what?
GME, NME or NLE in cats
Can FIV cause neurologic abnormalities?
YES.. Feline immunodeficiency virus encephalopathy.
Bacterial infections of the CNS is commonly associated with what in dogs and cats?
Direct extension or hematogenous spread.
What type of bacterial meningitis has a good success rate?
Otogenic intracranial infections
What age is distemper commonly seen?
12-16 weeks
What are the clinical signs of distemper?
Ocular and nasal discharge
Diarrhea
Hyperkeratosis of the foot and nose
Moist otitis externa
1-3 wks later = neuro signs.
What is the difference between chronic and acute distemper findings on MRI?
Acute = Gray matter only - temporal lobes
Chronic= White matter at the frontal and parital lobes
What is the incubation time for rabies?
1 week to 8 months
Toxoplasmosis in adults are resulted from what?
Reactivation of a chronic encysted infection
Common infection sites include:
Lung, CNS, MSK, ocular - dog and cat
Liver pancreas and heart - cat
What is seen on MRI usually with toxo?
MSK and CNS signs
LMN lesions commonly show what type of gait vs UMN?
LMN = choppy gait
UMN = swinging or floating gait.
Lesions only involving the central cord at C6-T2 will show more pronounced what?
LMN than UMN.
Horner’s syndrome is seen when what part of the spinal cord is affected?
T1-T2
Loss of cutaneous trunci is seen when what part of the spinal cord is affected?
C8-T1
The phrenic nerve originates from where in the spinal cord?
C5-C7
The cervical intumescenece is located at what vertebrae?
C4-T2
The lumbar intumescenece is located at what vertebrae?
L3-L5 in dogs
L3-L6 in cats
The spinal cord ends where for cats and dogs?
Cat- L7
Dogs - L6
When is a vertebral fracture considered unstable?
When two of the three compartments are damaged or displaced.
When does ascending myelomalacia occur?
First 5 days after a disc protrusion.
Where in the spinal cord is FCE commonly located?
TL or LS in big dogs
Cervical in little dogs
What breed is associated with young age FCE?
Wolfhounds
What are the most common infectious inflammatory disease in the spine?
Canine distemper
RMSF
Neosporosis
FIP in cats
Discospondyltitis has a prediclect for what sex?
Males
When looking for showering of emboli think of?
Urine culture
Prostate
Endocarditits
Most common tumors affecting the spinal cord of dogs?
Extradural tumors arising from the vertebral bodies. (bone tumors, mets and round cell tumors)
Most common intradural extramedullary tumor in dogs?
Meningiomas
Neuroepithelioma (neuroblastoma)
Nerve sheath tumors
Most common spinal tumor in cats?
Lymphoma
Neuroepithelioma is common where in the spinal cord?
T10-L1 in GSD and goldens
Differentials for peripheral vestibular disease includes all except:
a. Otitis media-interna
b. Geriatric vestibular disease
c. Chemical ototoxicity
d. Metronidazole toxicity
D
Most common primary aural tumors include:
a. SCC, ceruminous gland & sebaceous adenoma/adenocarcinoma, lymphoma
b. Lymphoma, metastatic, primary bone tumors, carcinoma
c. Sarcoma, SCC, ceruminous gland & sebaceous adenoma/adenocarcinoma
d. Lymphoma, primary bone tumors, SCC
A
True or False: The presence of cranial nerve deficits usually indicates peripheral vestibular disease
False
All the following diseases can cause central vestibular disease except:
a. FIP
b. MUE
c. Primary or metastatic neoplasia
d. Infarctions
e. All of these may cause central vestibular sign
A
Which intracranial tumors tend to develop in the cerebellopontomedullary region making central vestibular signs common:
a. Gliomas, metastatic
b. Meningiomas, choroid plexus
c. Meningiomas, gliomas
d. Metastatic, choroid plexus
B
True or False: Anatomical structures that can cause neck pain include: meninges, increased intracranial pressure, nerve roots, joints, bones, spinal cord, and muscles
F - spinal cord does not
All of these statements regarding SRMA are true, except for:
a. Breed associated include: beagles, bernese mountain dogs, boxers, german shorthaired pointers
b. Affected dogs are usually juvenile to young adults (6m-18moths)
c. Some dogs may have concurrent IMPA
d. The vast majority of dogs with SRMA are presented for a fever, have normal neurologic exam and reveal no cervical spine pain.
D = they usually have cervical pain
Since Distemper can affect both young and mature animals, MRI findings vary according to chronicity. Briefly describe and distinguish how acute vs chronic meningoencepahalitis would look on MRI
a. Acute: Gray matter, large area
b. Chronic: White matter, can be patchy, atrophy
What is this?
Look for tracting. Parasitic migration.
Which of these statements is correct regarding the cervical and lumbar intumescence:
a. Spinal cord segments of the cervical intumescence are located within C6-T2 ; spinal cord segments of the lumbar intumescence are located within L3-L5 (dogs and cats).
b. Spinal cord segments of the cervical intumescence are located within C4-T2 ; spinal cord segments of the lumbar intumescence are located within L3-L5 (dogs) L3-L6 (cats).
c. Spinal cord segments of the cervical intumescence are located within C6-T2 ; spinal cord segments of the lumbar intumescence are located within L3-L5 (dogs) L3-L6 (cats).
B
What are the most common organisms that have been isolated with discospondylitis:
a. Streptococus, Staphylococcus, E. coli, Brucella.
b. Listeria, streptococcus,e coli
c. Brucella, listeria, clostridium
A
What are the most common place in the spine where articular facet aplasia/hypoplasia occurs?
a. Thorax
b. Cranial lumbar
c. Caudal thorax and cranial lumbar
d. Lumbar
C
True or False: The most common spinal tumors affecting the spine in the dog are extradural tumors (primary bone or soft tissue)
T
Why are limb deficits worse in the hind limbs when a patient is suffering from a compressive cervical lesion?
- Due to the Schiff Sherrington reflex and the lack of inhibition to the hind legs.
- Hind limb nerve tracts are more superficially located in the cord than the forelimbs
- Hind limb motor nuclei are present in the cervical region
- There is commonly another lesions further caudally affecting the hind limbs as well
B
What area of the spine does the phrenic nerve originate from?
- C7-T2
- C3-C5
- C5-C7
- C4-C6
C
7,6,5 keeps the diaphragm alive
Which statement is most true?
- Traction stabilization can improve all forms of cervical spondyomyolopathy
- Neruonal abiotrophies affecting the gray matter commonly cause UMN signs
- The alar ligaments maintain alignment of the atlantoaxial joint
- Hypertrophy of the ligamentum flavum will commonly cause dorsal stenosis of the spinal canal.
D
Gray matter cause LMN signs
Transverse ligament maintains alignment
What breed of cat is associated with spina bifida and what other disease is it associated with?
- DSH and capital physeal fractures
- Maine Coon and hip dysplasia
- Manx and caudal agenesis
- Persians and hydrocephalus
C
A vertebral fracture is considered unstable when?
- The spinal canal is involved
- At least two of the three compartments are damaged
- The articular processes are involved.
- All fractures of the vertebral column are considered unstable.
B
Myasthenia gravis is a what kind of neuromuscular junction disease?
Post synaptic.
Traumatic neuropathies are common in what nerves in the cat and dog?
radial n.
Brachial plexus
Sciatic n.
Why is self mutilation occuring in regerative nerves?
Sensory n can cause abnormal sensation.
Lack of improvement for motor function for how long warrants amputation?
1 month
What are the most common nerves to get nerve shealth tumors?
C6-C8 and T1-T2
Trigeminal n.
Tumors involving what nerves can cause ipsilateral Horner syndrome?
T1-T3
Tumors involving the what nerves cause ipsilateral cutaneous trunci reflex?
C8-T1
Big differentials for facial nerve paralysis?
Idiopathic (75% dogs - 25% cats)
Middle/inner ear disease
Traumatic
Hypothyroidism in dogs
What is the clincal signs for trigeminal n paralysis?
Cannot close mouth.
What percentage of dogs with CN5 paralysis does horners or facial n paralysis happen also?
8%
Loss of sensory CN5 causes hyposensitization of the what?
Corneal surface - 30% of dogs.
Causes for Trigmeinal paralysis?
idiopathic (dog thing)
Neospora
Idiopathic polyneuritis.
Infiltrative neoplasia (lymphoma/leukemia)
What is hyperchylomicronemia?
Mutation causing delayed clearance of chylomicrons in the blood in cats
Causes lipid granulomas to form in skin and other tissues. This can cause mechanical compression of the nerves (Commonly the tibial and radial nerves)
What type of neuropathy is caused by caudal aortic thromboembolism?
LMN due to ischemia.
What type of neuropathy is congenital or inherited polyneuropathies?
LMN
Endocrine diseases that cause acquired chronic polyneuropathies?
Diabetic
Hypothyroid
Immune-mediated polyneuritis include (2)?
Primary immune
Systemic lupus erythematosus
Paraneoplastic disorders that cause LMN paraesis in what type of tumor?
insulinoma.
LMN disease (neruomuscular junction) etiologies?
Breed-associated degenerative neuropathies
Metabolic (hypothyroid, DM)
Paraneoplastic
Immune mediated (systemic lupus erythematosus)
Organophosphate
Acute
Coonhound paralysis - raccoon bite (acute polyradiculoneuritis) - Antibody deposition
Neospora polyradiculoneuritis
Tick paralysis
Botulism
M. Gravis
Differentials for rapid onset of LMN disorder?
Acute polyradiculoneuritis
Tick paralysis
Botulism
What diseases are associated with M. Gravis?
Thymoma
Immune-mediated (hypothyroidism and hypoadrenocorticism)
Drug induced with methimazole
M. Gravis is located where in the neuromuscular junction?
Incomplete disorder of the post-synaptic region.
What test is used to test for congenital M. Gravis or if serum test is not yet available?
Tensilon - short acting anticholinesterase.
What are the three forms of MG?
Generalized
Focal - just megaesophagus
Fulminating
What is the difference of MG acquired and congenital?
Acquire = antibodies
Congenital = just inherited lack of AChR.
What are the main feature of acute polyradiculoneuritis that differentiates it from Tick paralysis and botulism?
Hyperesthetic
Masticatory myositis is an IgG response to what?
Unique myofiber Type 2M only found in the
What type of dogs commonly get inflammatory myopahties?
Large breed dogs.
Differentials for optic neuritis dogs? Cats?
Dog = GME, Distemper, Tick borne enceplalitis virus, Ehrlichia, Idiopathic
Cat = FIP, Toxo, Crypto, histo, systemic hypertension, lymphoma
What breed is extraocular myositis common in, in dogs?
Goldens
Common clincal signs for masticatory myositis and what other diffferentials are there for this sign?
Unable to open mouth.
DDx: Retrobulbar abscess, mass, dental disease, TMJ problems
Muscle atrophy:
Trigem disorder, Polyneuropathy, hypothroid, hyperadrenocorticim, cancer cachexia.
Common clinical signs of extraocular myositis?
Acute exophthalmos
What sex is predisposed to extraocular myositis?
Female…goldens.
Polymyosistis in cats and dogs can cause what type of disorder in cats and dogs?
Megaesphagus.
What are the ddx for polymyositis?
Idiopathic
Systemic immune mediated disease (systemic lupus erythematosus)
Toxo, neospora
Systemic neoplasia
Thought to be a “preneoplastic syndrom” due to 20% of boxers developinig lymphoma in few months of diagnosis… Liver, spleen and bone marrow apsirates are warrated.
Dermatomyositis is seen in what breed of dogs?
Juvenile Collies
Megaesphogus can happen in this disease.
Glucocorticoids myopathy is a degernative myopathy that can rarely manifest as what?
Myotonia-like disorder with limb rigidity, stiff gait and hyperextension of all four limbs.
What cats are at risk for developing hypokalemic polymyopathy?
Acidiffying diets
Chronic renal disease
hyperthyroid
anorexia
Burmese kittens
What is a common sign of hypokalemic polymyopathy in cats?
Ventroflexion of the neck.
Inherited myopathies include?
Muscular dystrohy
Centronuclear myopathy of labs
Myotonia (involuntary muscle movement pst stimulation)
Muscular dystrophy occurs due to abscene of what protein and is what type of gene?
Absence of cytoskeletal protein dystrophin caused by gene mutation
This gene is x-linked and therefore mostly seen in male dogs (XY) and not females.
Muscular dystrophy occurs commonly in what breed?
Golden Retrievers.
Inherited myopathies are commonly seen in what age of dog?
young… 1-6 months
Cats too!
Myoclonus is defined as what and is commonly seen in what disease?
Rhythmic reptitive contraction of a portion of a muscle
Distemper.
Pathophys of tetanus?
Spores coloinate a wound
Vegetative form produces toxin (tetanospasmin)
Toxin ascends peripheral nerves to spinal cord
Toxin blocks the release of inhibitory interneurons causing tetany.
5-18 days after infection.
Muscular disorders of excerise intolerance or collapse?
Canine dyanmin-assoicated excerise-induced collapse in labs (7mo-2year, hyperthermia)
Border collie collapse (hyperhermia)
Scotty cramps (falling or somersaults)
Episodic falling in CKCS (3-7mo)
