Nervous - Final: A Comprehensive Overview (AKA S*** You Should Already Know)

T/F: Neurons have high energy needs and thus high glucose reserves

False, low glucose reserves, rely on blood

In what order are cells sensitive to hypoxia?

Neurons > Oligos > Astros > Microglia > Endo

(NOAME)

An example of a genetic defect affecting cell metabolism is what?

Cerebellar abiotrophy

An example of a genetic defect affecting cell migration/maturation is what?

Lissencephaly

An example of a genetic defect affecting elimination of by-products is what?

Lysosomal storage disease

An example of a deficiency affecting cell metabolism is what?

Thiamine deficiency/Sulfur excess,

Hypoglycemia

(Lack of energy)

An example of an excess nutrient competing for normal nutrient binding sites is what?

Selenium excess in pigs

T/F: Salt poisoning is often direct in ruminants and indirect in pigs

True

What areas are most sensitive to hypoxia?

Cerebral cortex,

Hippocampus, and

Purkinje cells

Which type of trauma is most severe when a stationary head is hit by a moving object (a bat)?

Coup

Which type of trauma is most severe when a moving head bounces against a stationary object?

Contrecoup

What poison causes laminar cortical necrosis by substituting for calcium ions?

Lead

What poison causes regional necrosis produced by yellow start thistle?

Nigropallidal encephalomalacia

What poison causes spongiosis due to hepatic dysfunction?

Ammonia

What fungal organism has a tropism for blood vessels?

Aspergillus encephalitis

What is an example of a pathogen entering via direct extension, common in cats?

Cuterebriasis

What is an example that has local replication in the muscle then travels through the nerves?

Rabies

What autoimmune disease is due to an influx of inflammatory cells forming perivascular cuffs?

Granulomatous meningoencephalitis (GME)

T/F: The dorsal arch of C2 should overlap C1

True

Which vertebra has a large, ventrally oriented transverse process?

C6

What is the anticlinal vertebrae?

T10/11

T/F: The disc space between T10/11 is often wider

False, narrower

Which vertebrae are often shorter to the adjacent ones?

C7 and L7

Which vertebrae have indistinct ventral borders due to the diaphragm?

L3 and L4

Which intervertebral foramina look like a horse head?

Lumbar

Which disc space is often wider compared to others?

L7 - S1

What is the first vertebrae will have dorsal spinous processes that superimpose over the intervertebral space?

T1 (C7 is more central)

Small, wedge shaped vertebrae leading to curvature of the spine are called what?

Hemivertebrae

A malformation at the junction of a spinal segment where the vertebrae assume characteristics of both segments is called what?

Transitional vertebrae

Failure of segmentation of vertebrae is called what?

Block vertebrae

What is the gold standard for imaging of most neurologic conditions?

MRI

T/F: You know how an MRI works

If you said "it is imaging of the a single proton (the hydrogen nucleus) which lines of the magnetic field for the protons, subsequently disturbs said fields, and monitors the release of energy as they return to their original orientation, allowing us to visualize brain matter in detail," then true

T/F: T2 weighted images are good for anatomy

False, T2 good for pathology, T1 for anatomy

Which MRI weight suppresses CSF signal?

FLAIR

Which MRI weight visualizes hemorrhage?

T2 star

Which MRI weight suppresses signal from fat?

STIR

Which MRI weight identifies areas of restricted fluid diffusion, like strokes?

DWI/ADC

Neurolocalize:

Seizures

Forebrain

Neurolocalize:

Dull mentation

Forebrain or brainstem

Neurolocalize:

Circling right

Right forebrain or right vestibular (circle toward lesion)

Neurolocalize:

Right postural reaction deficits

Left forebrain (contralateral), or

Right brainstem/spinal cord (ipsilateral)

T/F: The menace response utilizes pathways to the brain, while the PLR does not

True, need brain to blink

Neurolocalize:

Head tilt (right)

Listing (right)

Horizontal nystagmus, (fp left)

Right vestibular

(lean toward lesion, but look away)

Neurolocalize:

Decreased facial sensation (right)

Right trigeminal or brainstem

Neurolocalize:

Head tilt (left)

Mentally dull

Left central vestibular

Neurolocalize:

Postural reaction deficits (right)

Head tilt (left)

Horizontal nystagmus (fp right)

PR deficits indicate right brainstem.*

Rest indicate left vestibular.

LISTEN TO BRAIN

Right paradoxical (central) vestibular

*Also right cord or left brain, but this does not make sense with other signs

Neurolocalize:

Decreased gag reflex

Brainstem

Neurolocalize:

Tetraparesis and ataxia (x4)

Brainstem or cord

Neurolocalize:

Postural reaction deficits (x4)

Forebrain, brainstem, cord

Neurolocalize:

Head pressign

Forebrain

Neurolocalize:

UMN (x4)

C1 - C5

Neurolocalize:

UMN (PL)

T3 - L3

Neurolocalize:

LMN (TL)

UMN (PL)

C6 - T2

Neurolocalize:

LMN (PL)

L4 - S3

Neurolocalize:

Flaccid bladder, fecal incontinence (unless horse)

L4 - S1

Neurolocalize:

Patellar reflex absent only

L4 - L6 (femoral nerve)

Neurolocalize:

Pelvic limb withdrawal absent only

L6 - S1 (sciatic nerve)

Neurolocalize:

Perineal reflex absent only

S1 - S3 (pudendal nerve)

Neurolocalize:

Thoracic limb withdrawal absent only

C6 - T2 (radial/median/ulnar nerve)

Neurolocalize:

Cutaneous trunci absent at T13 bilaterally

T12

Neurolocalize:

Decreased tone and reflexes

Profound muscle atrophy

Peripheral nerve

Neurolocalize:

Atrophy of muscle with no reflex deficits

Decreased tone

Muscle

Neurolocalize:

Fatiguability with no atrophy and variable reflexes

NMJ

Neurolocalize:

Left thoracic limb monoparesis

L brachial plexus or peripheral nerve

Neurolocalize:

Collapse in pelvic limb with exercise

Normal gait when rested

NMJ

Neurolocalize:

Dull mentation

Vertical nystagums

Decreased pelvic withdrawal

Fecal incontinence

Central vestibular AND L4 - S3

Name that disease!

Degeneration of cerebellum without known cause

Affects younger animals

Diagnose with biopsy

Cerebellar abiotrophy

Name that disease!

Signs of sleeping during the day and restless at night

Diagnosed by visualizing small interthalamic adhesion

Treated with selegiline

Cognitive dysfunction

Name that disease!

Accumulation of CSF in cranium

Best diagnosed with MRI

Can be treated with a shunt to peritoneum

Hydrocephalus

Name that disease!

Caudal fossa is too small, leading to crowding

Often in Cavalier King Charles

Signs include phantom scratching and C1 - T2 myelopathy

Chiari-like Malformation

Name that disease!

More common in cats with panleukopenia

Symmetrical, non-progressive ataxia

Cerebellar hypoplasia

Name that disease!

Hyperexcitability due to lower neuronal threshold

Signs include facial rubbing and muscle tremors

Hypocalcemia

Name that disease!

Causes swelling of the brain cells

Treating aggressively can lead to dehydration and demyelination

Hyponatremia

Name that disease!

Caused by a deficiency of a certain hormone

Signs include vestibular dysfunction in older, large dogs

Hypothyroidism

Name that disease!

Due to a vascular bypass from the liver

Signs include abnormal behavior and pacing

Diagnosed on CBC with low BUN and elevated ammonia

Hepatic Encephalopathy

Name that disease!

Leads to decreased ATP production in the brain

Good prognosis if treated early

Thiamine deficiency

Name that disease!

Most common brain tumor in small animals

Histopath is the only definitive diagnosis

Meningioma

Name that disease!

Affects middle aged dogs, especially brachycephalics

Very poor prognosis

Glioma

Name that disease!

Causes unilateral masticatory muscle atrophy

Trigeminal nerve sheath tumor

What are the two mainstays of treatment for the conservative management of brain tumors?

Steroids at anti-inflammatory doses, and

Anticonvulsants

What is the dose range for physiologic, anti-inflammatory, and immunosuppressive doses of prednisone?

Physiologic: 0.1 - 0.2 mg/kg/day

Anti-inflammatory: 0.5 - 1.0 mg/kg/day

Immunosuppressive: 2 - 4 mg/kg/day

Name that disease!

Noninfectious inflammatory disease of toy breeds

Three forms: ocular, focal, and multifocal

Treated with immunosuppressive doses of prednisone

GME

Name that disease!

Noninfectious inflammatory necrotizing brain disease

Histopath is only definitive diagnosis

NME/NLE

Name that disease!

Infectious inflammatory disease of the respiratory tract

Signs include hyperkeratotic foot pads and nasal planum

Diagnosed with conjunctival scraping

Canine Distemper Virus

Name that disease!

Infectious inflammatory diseas that leads to obstructive hydrocephalus

Signs include central vestibular and forebrain signs

Diagnosed by high globulins

FIP

What form of FIP causes neurologic signs?

Dry

Name that disease!

Infectious inflammatory disease transmitted by saliva

Makes cats more susceptible to lymphoma

FeLV

Name that disease!

Virus locally replicates in muscle after bite

Should be considered in any acute, rapid neurologic condition

IFA detection in the brain is the gold standard of diagnosis

Rabies

Name that disease!

Most common mycotic encephalopathy of small animals

Cryptococcus neoformans

Name that disease!

Infectious inflammatory disease from ingestion of sporulated oocysts

Typically seen more in cats

Toxoplams gondii

Name that disease!

Infectious inflammatory disease similar to T. gondii

Neospora caninum

Name that disease!

Infectious inflammatory disease associated with Dermacentor ticks

Rocky Mountain Spotted Fever (Rickettsia rickettsii)

Name that disease!

Toxin that causes polioencephalomalacia

Treated with Succimer and calcium

Lead

Name that disease!

Toxin that is an acetylcholinesterase inhibitor, leading to too much ACh

Causes muscarinic and nicotinic signs (salivation, tremors, bradycardia)

Treated with 2-PAM to disrupt binding

Organophosphate

Name that disease!

Toxin that blocks GABA channels and facilitates sodium channels

Causes tremors and ataxia, mostly in cats

Is absorbed through the skin

Pyrethrin and Permethrin

Name that disease!

Toxin that blocks electron transport chain

Causes seizures and excitation

Bromethalin

Name that disease!

Snail poison

Causes seizures

DIagnose by frozen stomach contents

Metaldehyde

What is the formula for cerebral perfustion pressure?

Mean arterial pressure minus intracranial pressure

When cerebral perfusion pressure drops, it leads to ischemia in the brain, which is corrected by catecholamines that cause hypertension, which is compensated for with bradycardia. This is an example of what?

Cushing's Reflex

Ranking motor activity, brainstem reflexes, and level of consiousness are all part of what?

The Modified Glasgow Coma Scale