Neurology

Front 1

Funiculus

Back 1

large region of white matter in the spinal cord

Front 2

Fasciculus

Back 2

tract / collection of axons from a common origin going to a common destination

Front 3

Define a "Lower Motor Neuron".

Back 3

Efferent neuron connecting CNS with smooth (autonomic LMN) or skeletal (somatic LMN) muscle.

Front 4

The cell bodies of what neurons are found in the ventral horn of the spinal cord?

Back 4

LMNs innervating the axial & peripheral skeletal muscles.

Front 5

Injury to LMNs cause weakness characterised how?

Back 5

Depressed reflexes, decreased tone, and neurogenic muscle atrophy.

Front 6

Define an "Upper Motor Neuron".

Back 6

Motor system of CNS responsible for initiating voluntary movement and maintenance of tone & posture.

Front 7

Define the "pyramidal system".

Back 7

Direct connections between neurons in motor cortex & LMNs in spinal cord controlling movement.

Front 8

Define the "extrapyramidal system".

Back 8

scattered groups of interconnected neurons in the cortex & brainstem synapsing with LMNs in the brainstem & spinal cord to control movement and posture.

Front 9

Injury to upper motor neurons results in what characteristics?

Back 9

increased extensor tone (spasticity, stiffness); delay in the onset of protraction (swing phase) and longer stride; increased and primitive reflexes (loss of UMN inhibition of LMN reflex activity), inability to stimulate LMNs (UMN weakness)

Front 10

Describe paresis.

Back 10

"Weakness" caused by deficits in motor pathways or muscle. Movements regular and short-strided, occasional knuckling when placing limb. Can be due to UMN / lack of initiation of voluntary movement (weakness on tail pull while walking, increased reflexes) or LMN weakness.

Front 11

Describe ataxia

Back 11

"irregular movements", failure of muscular coordination. Caused by proprioceptive pathway deficits (split into 2 categories: general which includes both unconscious and conscious, and special ie. vestibular.)

Front 12

Describe cerebellar ataxia.

Back 12

Characterised by defects in rate, range, force and direction of movement of limbs. Broad based stance, inability to maintain head in proper position results in oscillation, there is hypermetria or hypometria, direction cannot be maintained and animal falls easily, often in exaggerated way.

Front 13

What are the 8 regions of the nervous system considered when making an anatomic diagnosis?

Back 13

1) prosencephalon (forebrain),
2) pons & medulla,
3) cerebellum, (often considered together w/ pons & medulla as the "caudal fossa"),
4) spinal cord divided into 4 regions:
a) C1-C5,
b) C6-T2,
c) T3-L3,
d) L4-Cd
8) Neuromuscular system

Front 14

What are the 5 components to the neurological examination?

Back 14

1) Sensorium,
2) Gait,
3) Postural reactions / muscle size,
4) Spinal reflexes / muscle tone,
5) Cranial Nerve function

Front 15

Define sensorium

Back 15

1) the part of the cerebral cortex that receives & coordinates all the impulses sent to individual nerve centers, 2) the state of an individual as regards consciousness or mental awareness. ie, signs of forebrain disease which are rated from 0=bright/alert to 5=comatose.

Front 16

What is DAMNIIIIT(v) ?

Back 16

Degenerative,
Anomalous,
Metabolic,
Neoplastic,
Inflammatory,
Infectious,
Idiopathic,
Iatrogenic,
Traumatic,
Vascular

Front 17

What is strabismus?

Back 17

Abnormal eye positions reflecting a lack of innervation of the extraocular muscles or a disorder with the vestibular system.

oculomotor nerve (somatic efferent) to medial rectus muscle = lateral & slightly ventral strabismus

abducent to lateral rectus muscle = medial strabismus

trochlear (in cat) = excessive extorsion in lateral position of dorsal aspect of vertical pupil

trochlear (in dog): fundic exam, position of superior vein at optic disc (normally vertical).

Stimulus is movement of fluid in semicircular ducts and stimulation of vestibular nerve (VIII) receptors in inner ear projecting impulses through vestibular nuclei into medial longitudinal fasciculus projecting to somatic efferent neurons of the oculomotor and abducent nerves.

Front 18

What is spontaneous nystagmus?

Back 18

Abnormal resting eye movement that occurs continuously regardless of head movement or position. Also known as resting nystagmus.

Front 19

What is abnormal positional nystagmus?

Back 19

With vestibular system discorders, the eye on the affected side fails to elevate completely when the head and neck are extended, giving vestibular strabismus. (Normally the eyes elevate to stay in the centre of the palpebral fissure)

Front 20

Which direction is nystagmus defined as?

Back 20

The direction of the fast phase of the eye movements. When vestibular disturbance involves inner ear receptors or the vestibular part of the vestibulocochlear nerve (VIII), the direction of the jerk is always OPPOSITE to the side of the lesion.

Front 21

Cerebellar disease signs:

Back 21

Cerebellar ataxia = inability to modulate the gait generating systems resulting in overflexion on protraction & abnormal limb placement, i.e., HYPERMETRIA. Also usually accompanied by loss of balance, loss of menace responses and intention tremor.

Front 22

Vestibular ataxia:

Back 22

loss of balance, lack of ipsilateral antigravity tone resulting in head tilt and tendency to lean, drift, fall, or roll to one side. Often accompanied by abnormal nystagmus.

Front 23

Brainstem cranial nerve signs:

Back 23

Visual dysfunction
Anisocoria
Strabismus
Dropped jaw
Changed facial sensation
Paralysis of eyelid, lip or ear
Dysphagia
Megaesophagus
Laryngeal paralysis
Paralysis of tongue
Head tilt, circling, nystagmus
Deafness

Front 24

Cerebellar pathology

Back 24

Cerebellum inhibits UMNs, coordinates movement... Pathology: Hypermetria, unconscious proprioceptive deficits, no weakness!
Asymmetrical damage cause increased in motor tone on the side of the lesion, leading to the head tilting away from the damage (‘paradoxical vestibular signs’).

Front 25

Common infectious / inflammatory diseases that cause central vestibular defects in dogs?

Back 25

canine distemper
toxoplasmosis and neosporiosis
fungal
rickettsial
GME
SRME

Front 26

Common infectious / inflammatory diseases that cause central vestibular defects in cats?

Back 26

FIP
FeLV
Toxoplasmosis
Cryptococcosis

In cat also
Thiamine deficiency
Organophosphate toxicity

Front 27

Describe the effects of GME in dogs?

Back 27

Granulomatous meningoencephalitis: patient presents with vertical nystagmus, long tract signs, and circling with incoordination.

Can be peracute, acute & progressive, chronic. In brainstem, tends to be a multifocal inflammatory disorder. Responds temporarily to immune suppression. Histologically causes multifocal meningoencephalitis due to proliferation
of reticulohistiocytic cells. Lesions also show multinucleated giant cells.

Front 28

What are the predicted neoplasms in the brains of cats or dogs?

Back 28

Cats get meningiomas.
Brachycephalic dogs get gliomas.
Dolichocephalic dogs get Oligodendrogliomas.

Front 29

What are common diseases associated with the spinal cord?

Back 29

Intervertebral disc disease
Fibrocartilaginous embolism
Vertebral column fractures
Inflammatory spinal cord diseases
Lumbosacral Malarticulation & Malformation
Chronic degenerative radiculomyelopathy
Vertebral anomalies
Spinal tumours

Front 30

What is the Hansen classification?

Back 30

A system of predicting degenerative disc disease:

Type I = Extrusion
Chondrodystrophic breeds
Young (3 to 6 years)
Disks in these dogs  cartilage
↑ risk of rupture of annulus & herniation of nucleus pulposus into vertebral canal

Type II = Protrusion only
Nonchondrodystrophic breeds
Older dogs
Fibrous degeneration

Front 31

What is a seizure?

Back 31

a paroxysmal, transitory disturbance of brain function that has a sudden onset, ceases spontaneously and has a tendency to recur. Usually associated with autonomic disturbances such as urination, salivation and defecation.

Front 32

What is epilepsy?

Back 32

A recurrent seizure disorder irrespective of the cause.

Front 33

What are the different stages (phases) of seizures?

Back 33

prodrome - the period prior to a seizure, hours or mintues. may include behavior abnormalities, restlessness, or changes in daily behavior patterns such as eating or sleeping.

aura - the sensation or feeling immediately prior to a seizure. most commonly expressed by animals as behavior abnormalities.

ictus - the actual seizure event lasting less than a few minutes (unless during status epilepticus, continual seizure activity -lasting over 5 minutes- without a break in the seizure cycle.)

postictal period - the period following ictus, may last minutes, hours or up to days. Behavior abnormalities predominate, ranging from somnolence to hiding to agitation and frenzied activity. physical and neurological exam abnormalities may be present during this phase.

Front 34

What are the classes of seizures by pattern?

Back 34

Generalized - affecting the entire body simultaneously.
- generalized tonic clonic or grand mal is the most common seizure recognized in animals.

Focal seizures - remain localized to one body region. generally, a clinical abnormality on one side of the body is the result of a seizure focus in the contralateral supratentorial sturctures and associated with structural brain disease.

Focal progressing to Generalized.

Inconclusive evidence suggests fly biting, flank sucking or tail biting may result from a seizure focus.

Front 35

What are they classes of seizures by type?

Back 35

Idiopathic,

Structural -
Primary intracranial disease-
anatomical or structural,

Metabolic -
Extracranial disturbance-
-endogenous diseases,
-exogenous diseases

Front 36

Example list of Differential Diagnosis for sezure discorder:

Back 36

Idiopathic: >100,000 dogs in US

Metabolic:
hypo- or hyperglycemia,
liver disease,
renal disease,
electrolyte disturbances,
toxins,
anaemias,
cardiopulmonary disease

Structural:
hydrocephalus,
storage diseases,
neoplasia (primary or secondary brain tumor),
inflammatory diseases (non/infectious encephalitis),
trauma / injury,
vascular-based diseases

Intracranial disease causing: physical invasion and/or destruction of neurons, metabolic alterations in neuronal or glial cells, impairment of vascular supply to normal tissues (ischemia or hypoxia), impairment of autoregulation, hemorrhage (intraparenchymal or intraventricular), irritation, obstruction of the ventricular system, edema formation, production of physiologically active substances, and increases in ICP.