Computer Test - Neurological system Flashcards
What is a nystagmus ?
Involuntary movement of eyeballs
What are the characteristics of Horner’s syndrome ?
Lossof sympathetic innervation → Myiosis Ptosis Enophtalmos \+ prolapse of the 3rd eyelid
Which is true about ataxia ?
- Incoordination
- Muscle weakness
- Vestibular malfunction
Incoordination
CNS is involved, not the peripheral nerves
Signs of UMN disease ?
Hyperactive reflexes, increased tone
What are proprioception tests ?
Complex responses involving spinal reflexes and central coordination for normal movement and posture
- Wheel barrow
- Hopping
- Hemi-hopping
- Correction / Knuckling over
- Crossing over
- Tactile and optical placing reactions
- Reflex stepping
Symptoms of a generalized seizure ?
Diffused origin within cortex, thalamus, brainstem → so all muscles effected and general symptoms seen → excitation or loss of consciousness
What is the procedure of the nervous system exam ?
Ask
Watch
Touch
Pain
Slap test explanation ?
,Hit the wither of the horse -> slap test on arytenoïds → N; vagus recurrens
Is auto-mutilation a pathological behaviour ?
Yes
What indicates consciouness ?
- Ability to learn
- Eat
- Sleep
- Walk
- Ability to remember
- Make noise
- Ability to learn
- Eat
- Walk
- Ability to remember
What is incorrect concerning spinal cord sampling ?
- Biopsy
- Blood sample
- US of abdominal cavity
- FNA
- Biopsy
- Blood sample
- US of abdominal cavity
Which nerve(s) is/are responsible for panniculus reflex ?
Afferent : spinal segments, center = C7-T1
Efferent : m. cutaneous trunci
Symptoms of vestibular ataxia ?
- Head tilt
- Nystagmus
- Animal lean and fall to affected side
- Muscle weakness
- Goose stepping
- Circling
- Head tilt
- Nystagmus
- Animal lean and fall to affected side
What do you examine with the “swinging light test” ?
N. opticus + N. oculomotor
Nerves involved in the perineal and anal reflexes ?
N. pudenlus (afferent and efferent)
N. rectalis caud. (efferent)
Signs of damaged trigeminal nerve ?
Sagging lower jaw
Trismus
Tic
LMN lesion signs ?
Diminished or absent reflexes
Decreased or absent tone
Rhythmic oscillating muscle twitch :
- tremor
- tic
- tetany
Tremor
Instruments needed for neurological eReflex hammer Penlight Arterial clamp Needle Stethoscope Glovesxams ?
Reflex hammer
Penlight
Arterial clamp
Needle
What is anisocoria ?
Unequal pupil size
Which are methods of neurological - X-ray
- EEG
- CT
- MRI
- MIR
- CBC
- Pathogen detection
- Cerebrospinal fluid analysisexamination ?
- X-ray
- EEG
- CT
- MRI
- CBC
- Pathogen detection
- Cerebrospinal fluid analysis
Signs of conscious pain perception in dog ?
- leg withdrawal
- leg extension
- crying
- bitting towards the hand
- lifting the head up
- crying
- bitting towards the hand
What are the reduced mental states ?
- Dementia
- Stupor
- Indolentia
- Somnolentia
- Delirium
- Coma
- Furor
- Aggressive
- Excitatio
- Dementia
- Stupor
- Indolentia
- Somnolentia
- Delirium
- Coma
What extra exams can ber ordered for a neurological patient ?
Xray, EEG, CT, cerebrospinal fluid analysis, CBC, detection of pathogens, MRI
Pupillary light reactions nerves ?
N. opticus, and N. oculomotorus + vegetative system
Examination order ?
AWTP = Ask Watch Touch (palpation/percussion/postural reactions and reflexes/sensitivity of skin & Mm) Pain(ful manipulations & percussion)
Examination of the neurological system ?
Inspection
Palpation
Percussion
- Extra exams :
- X-ray – see e.g. disk space of vertebrae (Spondylosis), inflammation ossificiation of tympanic bulla (dog)
- EEG (Electro encephalography) – but needs sedation. Lower significancy in vet medicine
- CT – Computed Tomography : cross section imaging – X-ray takes rotational multiple images, but has higher resolution → computer reconstructs the image
- MRI – Magnetic Resonance Imaging : cross-sectional imaging but uses no radiation (hydrogen atoms change in magnetic and radio frequency fields). Better for soft tissue : improved anatomic details
- CSF = Cerebro-Spinal Fluid – via Occipital punctures (released under pressure → suggests high ICP (hydrocephalus…). Normal - “water-clear, transparent fluid”, liquid as water . EDTA sample (non-EDTA sample for PCR)
- Blood count, blood chemistry
- Detection of pathogens
Abnormal head positions ?
- Opisthotonus – “stargazing”
- Lateral head turning, +/- walk in circle
- Head tilt – axis of head is NOT in a perpendicular angle (usually ipsilateral to lesion). Normal consciouness in most of cases, but huge inbalance
- Paralysis of neck muscles
Abnormal spine positions ?
- Kyphosis – permanent dorsal deviation vs pseudo-kyphosis (when back arched in pain) –
- Lordosis – ventral deviation
- Scoliosis – lateral deviation – rare in animals
NOT primary neurological disorder
Examination of head ?
- Shape of skull, symmetry
- Mobility of head/neck/jaws
- Ears (dropping/pointing)
- Lips
- Pain at palpation
Examination of the face ?
Facial expression (eyelids, nostrils, ears : often pulled by muscles towards healthy side)
- Uni/bilateral function of facial muscles
- Detailed eye exam (eyeballs + pupils)
Examination of vertebral column ?
Inspection (shape, position)
Palpation (careful bending if pain)
Regulation of mental state ?
Regulated by thalamocortex, the brain influences the mental state
→ ARAS – ascending reticular activating system (activates cortex)
Definition of consciousness ?
Aware of surroundings and has ability to learn and remember
Decreased levels of consciousness ?
- Dementia – loss of intelligence, alert but inappropriate reactions
- Start eating but forget hay is in mouth
- Stupor – responds only to strong stimuli
- Indolentia – uninterested in surroundings
- Somnolentia – drowsy but can be woken
- Delirium – uncoordinated, as if drunk
- Coma – cannot be woken, loss of consciousness
- Possible indications – Lead poisoning, hydrocephalus
Increased levels of consciousness ?
Excitation, excitement Aggression, attacking Furor – rage
Involuntary movements ?
Opisthotonus or “stargazing”, head tilt, lateral turn of the head o
Circling, walking in circle clockwise or anticlockwise, compulsive walking (pacing) – usually cortical abnormality, and restless at night
Special abnormalities ofconsciousness ?
Hallucinations: illusory perception; a common symptom of severe mental disorder
Paraesthesia – psychogenic dermatitis – constant scratching of fur vigorously
Automutilation or semitmutilation
Seizure definition ?
“Sudden extreme change in muscle contraction and behaviour and muscle tone due to abnormal brain function” : a state with unvolutnary muscle contractions
Does seizure have only neurological causes ?
NO
Can be hypo-calcaemia, hypo-glycaemia, hepatic encephalopathy (HE), severe renal failure causes uremic failure….
Classification of neural seizures ?
- According to muscle function
- Tonic – continuous contraction causes spasm (entire musculature) : spasm of a muscle group
- Clonic – rapid contraction but then relaxation – rhythmic - Tonico-clonic – mixture of two
- According to focus or centre of seizure
- Generalised – diffuse origin within cortex, thalamus, brainstem – so all muscles affected and “general” symptoms seen so causes excitation or loss of consciousness
- Focal – only smaller region of cerebro-cortex gets excited e.g. temporal or parietal lobe – so only a small portion of muscles affected – can cause tail chasing, fly catching etc
Definition of epilepsy ?
= Recurring seizures with a certain time frame
Animal between seizures is normal
+ common in dogs
Definition of status epilepticus ?
When seizure does not stop and becomes continuous (without or with minimal normal periods) – often causes more cerebral damage
Definition of petit mal ?
Short-term loss of consciousness and increased muscle tone – rare in animals (e.g. Canine distemper)
Definition of grand mal ?
Severe tonico-clonic convulsions of muscles with loss of consciousness
Other involuntary changes of muscle tone NOT necessarily connected to CNS ?
- Tetanus – sustained tonic contraction with no twitching i.e. stiffness Usually due to Cl. tetani
- Horses – tail biting in early stages, and raised tail, difficult to breath, wide stance
- Cattle – episthotonus (extensor muscle stronger than flexors)
- Dogs – spastic tetra-paresis –can affect puppies when shedding teeth and chewing wood – “flying dog stance” → Risus sardonicus facial expression, and locked jaw due to chewing muscle spasm (Trismus)
- Tetany – violent muscle twitching of whole body
Esp. due to hypo-calcaemia (+ panting, and high temp)
*Tremor – mild form of tetany – oscillating muscle twitches : regular, rhythmic trembling (oscillation) of muscles . Shaking, shivering
- Tic – repetitive non-rhythmic contraction of one muscle
Often seen in distemper – can often feel temporal muscle tic by palms on top of head - Myoclonia – abrupt, rhythmic contractions of one muscle group
E.g. just flexors of a limb - Fibrillation – non-coordinated of individual muscle fiber twitching
Less severe form of tremor
Postural reactions list ?
Wheel barrowing test Hopping test Correction test Crossing over test Tactile and optical placing reactions Extensor postural thrust reaction
Wheel barrowing test description ?
Elevate hind legs of patient, it should be able to do steps without falling over
With or without vision
Hopping test description ?
Evaluate every foot one by one by lifting the remaining three legs, shift centre of gravity to lateral reaction, animal should be able to follow this movement
One leg
Hemi-walking
Correction test description ?
Bend over foot and place it on the ground
→ should replace it immediatly
Crossing-over test description ?
Cross limbs in front of each other
→ Should replace it immediatly
Tactile and optical placing reactions description ?
Tactile: shield patient’s eyes and place animal close to table so it touches the table with skin
→ Should place foot on it
Optical: approach table without covering the eyes
→ animal should put legs on table before it touches it
Extensor postural thrust reaction description ?
Take the dog behing the armpits, lift him totally from the floor, and then put him down on his hindlimbs
→ Should step back and rebalance himself
Define ataxia ?
Lack of coordination in muscle function without muscular weakness The CNS is involved, not the peripheral nerves.
Classification of ataxia ?
- By signs :
- Static: signs are also seen in animals that are not moving
- Locomotive: Signs seen during movement
- Intentional: Tremor of head when fine adjustment of position is demanded) – rare
- By anatomical origin:
- Cortical/Cerebral (proprioceptive):
Less common (except old animals)
Occurs together with behavioural changes
Circling
May be muscular weakness
- Brain stem: Swaying from side to side Rolling Involuntary movements Wide-based stance
- Cerebellar:
Exaggerated steps (wide based stance: Hypermetria, dysmetria)
Nystagmus (involuntary movement of eyeballs)
No muscular weakness - Vestibular:
Ipsilateral head tilt (towards side of lesion)
Nystagmus
Tendency to fall on ipsilateral side → cortex and behaviour are not effected!
Bilateral vestibular ataxia – rare (cats) - Spinal (uni-/bilateral):
As the peripheral reflex arch is involved, paresis, paralysis is often seen
Hind limbs are always affected.
Paresis/lysis/plegia definition ?
Abnormal posture of movement due to reduced (or increased) muscular strength without incoordination. Extra-neural forms are frequent.
How to diagnose a paresis/lysis/plegia ?
Inspection, palpation, evaluation of muscle tone:
Atony, Hypotony (reduced muscular tone)
Hypertony
Schiff. Sherrington phenomenon: present in acute spinal trauma between T2 and L3; the rear limbs will be paralyzed and the thoracic limbs are stiff and extended
Classification of paresis/lysis/plegia ?
- By severity
- Paresis and paralysis/plegia (partial or complete loss of strength)
- By the affected limbs of the body
- Monoparalysis/plegia/paresis (only one limb affected; peripheral nerve damaged)
- Tetra- (all limbs are affected)
- Para- (both limbs are affected)
→ Paraplegia anterior
→ Paraplegia posterior - Hemiparalysis (limbs on one side of body are affected)
- By the quality
- Rigid, spastic
- Atonic, flaccid
- By origin
- UMN (upper motor neuron): injury is above spinal reflex centre (spinal nerve nucleus). The UMN regulates/decreases the activity of the LMN → muscle tone will be increased
-LMN (lower motor neuron disease): injury is in spinal centre or below it
UMN is regulating “too much” because the LMN is damaged → decresed muscle tone
LMN disease signs ?
Diminshed/absent reflexes
Decreased/absent tone
UMN disease signs ?
Hyperactive reflexes
Increased tone
List of 12 cranial nerves ?
I. N. Olfactorius II. N. Opticus III. N. Oculomotorious IV. N. Trochlearis V. N. Trigeminus VI. N. Abducens VII. N. Facialis VIII. N. Vestibulocochlearis IX. N. Glossopharyngealis X. N. Vagus XI. N. Accessories XII. N. Hypoglossus
Evaluation of the CN n°1
I. Olfactorius
Smelling
→ Methods:
- Using strongly stimulatory compounds or food
- Substance should not irritate the nasal mucosa (involvment of the N. Trigeminus V.)
- Hyposomia/anosomia = partial or complete loss of smell
Evaluation of the CN n°2
II. Opticus
Vision = importance of the history !!
- Examination of the vision: falling cotton test (tracking, leading the animals to objects
- Pupillary nerve is involved in the development of:
- Pupillary (light) reaction (direct and consensual)
Cover eyes before testing
Evaluation of pupil constriction
Efferent nerve/motor part: N. oculomotorius - Threat/menace reflex (response)
Response: blinking
Efferent part: facial nerve - Optical placing test
Evaluation of the position and movement of the eyeballs
III. Oculomotorius
IV. Trochlearis
V. Abducens
- Physiological nystagmus: Turning the head from side to side and up and down elicits involuntary eye movements
- Pathological nystagmus: could be horizontal, vertical or rotatory
- Strabismus: uni- or bilateral abnormal position of the eyeball (they’re not parallel)
- N. Oculomotorius paralysis: Str. Divergens (ventrolateral strabismus)
- N. Trochlearis paralysis: medioventral strabismus
- N. Abducens paralysis: Str. Convergens (medial strabismus) and exophthalmos
If the animal presents a medial strabismus, which nerve is damaged ?
IV. Trochlearis
= Strabismus medioventralis
If the animal presents a ventrolateral strabismus, which nerve is damaged ?
III. Oculomotorius
= Strabismus divergens
If the animal presents a convergent strabismus, which nerve is damaged ?
VI. Abducens
= Strabismus convergens
Evaluation of the pupils
Anisocoria: Uneven size of pupils
Mydriasis: Dilation of pupils
Myosis: Constriction of pupils
(Claude Bernard) Horner’s syndrome: Loss of sympathetic innervation results in
- Myosis
- Ptosis (Drooping or falling of upper eye lid)
- Enophthalmos (and prolapse of the third eyelid)
Evaluation of the CN n°5
V. Trigeminus
= Mixed nerve having sensory and motor fibres
- Sensory part: involved in the development of
- Eyelid (palpebral) reflex (efferent/motor nerve: facial) along with VII. nerve
- Corneal reflex (efferent nerve: facial)
- Motor part
- Tic (repeated contractions of chewing muscles)
- Sagging lower jaw (paralysis – caused by central/peripheral injury of the nerve)
- Trismus (Tonic spasm of chewing muscles – might also be caused by myositis)
- Further tests of motor function: Prehension of food, drinking and chewing processes
Evaluation of the CN n°7
VII. Facialis
* Mixed nerve (mainly motor function)
Uni-/Bilateral paralysis of the nerve is known
- Nerve is involved in:
- Eyelid reflex
- Threat (menace) reflex
- Corneal reflex
- Investigations to diagnose facial paralysis:
- Position of the ears (drooping on affected side)
- Position of the upper eyelids (Ptosis, following paralysis of the orbicular eye muscles)
- Moving of the nostrils (away from the affected side)
- Sagging of lips on affected side
- Forms of facial paralysis:
- Severe (intracranial, intrapetroseal lesion): Drooping ear, lip, the nose pulled toward the normal side (most obvious in horse)
- Mild (peripheral lesion): Pointing ear, ptosis, sagging lips
Evaluation of the CN n°8
VIII. Vestibulotrochlearis
Two-division nerve, involved in hearing (trochearis) and postural (vestibulo) reactions
- Examination of hearing (cochlear division of the nerve)
- Hearing ability tested by speaking, whistling, clapping
- Deafness (congenital, acquired)
- Examination of dysfunctions of the peripheral vestibular system (vestibular division of the nerve)
- The mental status and the postural reactions are regularly normal
- Inspection:
o Position of the head (ipsilateral head tilt)
o Falling towards the affected side
o Nystagmus (usually horizontal, the slow phase is toward the lesion)
o (Strabismus) o (Horner’s syndrome) - Examination of dysfunctions of the central vestibular system (cerebellar and brain stem lesion)
- Severe asymmetric ataxia (circling, Hypermetria)
Evaluation of the CN n° 9 & 10
IX. Glossopharyngeus
X. Vagus
Malfunctions cause dysphagia, weak/absent gag (swallowing reflex), laryngeal paralysis
- To study:
- Swallowing/gag reflex (sensory part: glossopharyngeal nerve, efferent nerve: n.vagus). A cranial reflex can be stimulated by fingers (in SA) or with a nasogastric tube (in LA). Alternative: little amount of water from syringe
- Laryngeal paralysis (recurrent laryngeal nerve of n.vagus) important in horses, dogs
- Consider rabies!
- Bilateral paralysis : very severe dyspnoe, stridor, exaggerated breathing
- Unilateral paralysis : change in voice, unsuccessful barking
Evaluation of the CN n° 11
Deficit from an injury to this nerve are not frequently recognized in animals.
→ Palpate m.trapezius, sternocephalicus and brachiocephalicus for atrophy Sagging of head
Evaluation of the CN n°12
Responsible for protruding and retracting the tongue (after feeding, usually dogs lick their nose. Possibility to offer food on the floor so the dog needs to lick it up
- Bilateral lesion: Protrusion of the tongue with weak retraction
- Unilateral lesion: ipsilateral deviation of the tongue (towards the healthy side : because of muscle tone to this side !!)
Definition of a reflex
An involuntary movement or other immediate response of an organ to an appropriate stimulus, without the aid of the will or without even entering consciousness.
5 scales to evaluate a reflex ?
0 = areflexia 1 = hyporeflexia 2 = normoreflexia 3 = hyperreflexia 4 = hyperreflexia with clonus ( a series of rapid contractions of a muscle in response to one stimulus)
Abnormal reflexes ?
Areflexia , hyporeflexia, hyperreflexia, hyperreflexia with clonus
Reflex irradiation: a reflex elicited in a larger area / muscle group than expected
Contralateral (crossed) reflex: a reflex elicited in response to a stimulus applied to the other side of the body
2 types of normal reflexes ?
Proprioceptive (a reflex that is initiated by a stimulus to a proprioceptor (mechanoreceptor)
Nociceptive
Define & describe proprioceptive reflexes
A reflex that is initiated by a stimulus to a proprioceptor (mechanoreceptor)
- Thoracic limb reflexes
- Extensor carpi radiali reflex (important!): n.radialis (afferent + efferent)
- Triceps reflex: n.musculocutaneus (afferent + efferent)
- Biceps reflex : place your finger on the tendons of biceps brachii muscle, cranial and proximal to the elbow. The finger is struck ! Or tendons are directly strucl
- Pelvic limb reflexes
- Patellar (quadriceps) reflex (most important!): femoral centre L4-L6
- Achilles (gastrocnemius) reflex: n.ischiadicus (afferent + efferent)
- Evaluate the tail tone
Define & describe nociceptive reflexes
- Anal/perianal reflexes (movement of the tail/perineal region if touched)
- Afferent: n.pudendalis
- Efferent: n.pudendalis, n.rectalis caudalis
- Panniculus reflex
- Afferent: spinal segments, centre: C7-T1
- Efferent: m. cutaneus trunci
- Touch the skin along the neck and trunk with a pointy tool. There can be hypersensitivity or hyposensitivity
- Flexor (withdrawal) reflexes of limbs:
- Not conscious pain sensation (but can show behavioral reaction if the information is integrated in the brain)
- Forelimb: Centre C6-T1
- Hindlimb: L (4)6-S1
Examination of pain perception
The last step in neurological examination. Mostly spinal reflexes belong here, but pain sensation should be studied on all parts of the body.
1. Superficial/cutaneous pain perception
2.
Evaluate the superficial pain perception
Assessed mainly by pinching/pricking with a pencil/needle or light pressure of skin (as in panniculus and flexor reflex)
- Normal response:
- Local (skin twitch, leg withdrawal) via spinal reflex arch only
- Behavioural (crying, biting, turning to the direction of pain) via long pathways: receptor-spinal ganglion-thalamus-cortex and back
- Evaluation :
- Normaesthesia
- Hyperaesthesia
- Anaesthesia
- Paraaesthesia
Sensitivity of the mucous membranes, anal skin and the fingers can be similarly analysed during reflex studies.
Deep pain perception evaluation ?
Testing is not necessary if superficial pain perception is present.
Assessed by squeezing a digit or the rim of a tail with a haemostat (arterial clamp) or with a strong pressure in large animals.
Horse: step on the rim of the hoof
Evaluation of the vertebral column
Palpation & percussion of the spine
Cervical pain by passive movements of the head and neck
Back pain evaluation by caudal to cranial palpation of the transverse processes, supporting the belly to avoid putting weight on limb joints
History is also important
