Neurology AI Flashcards
How can abnormal eye movement be observed if the vestibular system is challenged?
By changing the head position or putting the patient on its back.
What is the purpose of testing corneal sensation?
To assess the response to touching the cornea and observe globe retraction and/or blink.
Which cranial nerves are involved in corneal sensation?
CN V (afferent pathway) and CN II and CN VI (efferent pathways).
How can the response to stimulation of the nasal mucosa be evaluated?
By touching the nasal mucosa and observing withdrawal of the head.
What cranial nerves are involved in the response to stimulation of the nasal mucosa?
CN V (afferent pathway) and a response.
What is the purpose of testing jaw tone?
To assess the resistance of the jaw to opening the mouth.
How can tongue movement be assessed?
By observing tongue movement and symmetry.
Which cranial nerve is responsible for tongue movement?
CN XII
How can gagging and swallowing be evaluated?
By offering food or stimulating the hyoid bone externally.
Which cranial nerves are involved in gagging and swallowing?
CN IX, X, XI
Why is evaluating the olfactory nerve challenging?
Because it remains subjective and not commonly performed.
What additional information may be required to evaluate the olfactory nerve?
A history of anorexia and other neurological signs.
How is the list of differential diagnoses formulated?
Based on signalment, onset, progression, and response to therapy.
What are the possible categories for differential diagnoses (excluding VITAMIND and DAMNITV)?
Vascular, Inflammatory, Trauma/toxin, Anomalous, Metabolic, Idiopathic, Neoplastic/nutritional, Degenerative.
What are the different localizations for neurological abnormalities?
Intracranial (forebrain, brainstem, and cerebellar), spinal (C1-C5, C6-T2, T3-L3, L4-S2), and neuromuscular.
What does a forebrain syndrome include?
Cerebrum (cerebrocortical grey matter, cerebral white matter, and basal nuclei) and diencephalon.
What is the main function of the cerebral cortex?
Behavior, vision, hearing, fine motor activity, and conscious perception of touch, pain, temperature, and body position.
What is the main function of the cerebral white matter?
Conveying motor and sensory function instructions.
What is the main function of the basal nuclei?
Muscle tone and initiation/control of voluntary motor activity.
What is the main function of the diencephalon?
Sensory integration, control of autonomic and endocrine function, sleep, consciousness, olfactory functions, vision, and pupillary light reflex.
What are the possible neurological examination findings in a forebrain syndrome?
Altered mentation/changes in behavior, possible contralateral lack/decreased menace, normal gait and possible abnormal posture, possible contralateral deficits in posture, normal to increased contralateral muscle tone, facial and body contralateral absent to decreased sensation, seizures/hemi-neglect syndrome, cervical hyperaesthesia, rarely movement disorders.
What is the function of the cerebellum?
To regulate and coordinate motor activity, maintain equilibrium, and preserve normal body position at rest or in motion.
What are the possible neurological examination findings in a cerebellar syndrome?
Ipsilateral menace deficits, vestibular signs/anisocoria, intention tremors/hypermetria, ataxia/broad base stance, delayed initiation/exaggerated proprioception, normal to increased spinal reflexes/ upper motor neuron (UMN) muscle tone.
What are the clinical signs of proprioceptive ataxia?
Loss of awareness of limb position in space.
What are the clinical signs of vestibular ataxia?
Head tilt and a tendency to lean, drift, fall, or roll to one side.
What are the clinical signs of cerebellar ataxia?
Abnormal ‘uncontrolled’ limb movements and hypermetria.
What is the difference between paresis and plegia?
Paresis is weakness or inability to generate movement voluntarily, while plegia is complete loss of voluntary movement.
What is the difference between tetraparesis/plegia and hemiparesis/plegia?
Tetraparesis/plegia affects all four limbs, while hemiparesis/plegia affects one side of the body.
What is the difference between paraparesis/plegia and monoparesis/plegia?
Paraparesis/plegia affects the hind limbs, while monoparesis/plegia affects only one limb.
What are the criteria for LMN paresis?
Difficulty supporting weight, short strides, flaccid motor function, decreased segmental reflexes, and decreased resting muscle tone.
What are the criteria for UMN paresis?
Abnormal limb position, stiff and ataxic gait, delayed protraction collapse, spastic motor function, normal to increased segmental reflexes, and normal to increased resting muscle tone.
What is proprioception?
Awareness of the position and movement of the head, body, and limbs.
Where are the proprioceptive receptors located?
In the joints, tendons, muscles, and inner ear.
What tests can be used for proprioceptive testing?
Paw positioning, hopping, placing and visual placing, wheelbarrowing, extensor postural thrust, hemiwalking, and paper sliding tests.
Which postural reaction test is commonly used in dogs for proprioceptive positioning?
Paw positioning.
How is the paw positioning test evaluated?
By turning the paw over and determining how quickly the animal corrects the position.
Why is it important to support the animal’s weight during the paw positioning test?
To improve test sensitivity and ensure the animal is standing firmly on all four limbs.
What is the purpose of segmental spinal reflexes?
To help localize the lesion further into different spinal cord segments and monitor disease progression.
What makes up the peripheral nervous system?
12 pairs of cranial nerves and 36 pairs of spinal nerves.
What do peripheral nerves contain?
Motor and sensory axons.
Where do motor axons extend from?
Neurons located in the ventral horn of the spinal cord or the grey matter of the brainstem.
Where do sensory axons have their cell body?
In the dorsal root ganglion or in homologous ganglia of cranial nerves.
How do most spinal nerves leave the vertebral canal?
Through the intervertebral foramina formed between pedicles of adjacent vertebrae.
What reflex can be performed to evaluate cervical intumescence and brachial plexus nerves?
Withdrawal reflex.
What reflexes can be performed on the pelvic limbs?
Not mentioned in the course notes.
Why is neuroanatomical localisation important in formulating differential diagnoses?
To prevent inappropriate diagnostic tests and costly experiences.
How can the neurological examination be divided?
Into six sections: mentation, gait evaluation, postural reaction testing, segmental spinal reflexes, evaluation of pain and sensation, cranial nerve examination.
Is there a specific order to follow during the neurological examination?
No, but it’s best to establish a routine to avoid missing any section.
What are the different classifications of mental status?
Normal, disorientated, drowsy/obtunded, stuporous, comatose.
What are some abnormal behaviors that can accompany altered mental status?
Aggression, compulsive walking, loss of learned behavior, head pressing, stargazing, hemi-neglect syndrome.
What can altered mental status be caused by?
Intracranial pathology or metabolic abnormalities such as hypoglycemia, hepatic or uraemic encephalopathy.
How many different postures should be differentiated?
Three different postures: Schiff-Sherrington, decerebrate rigidity, decerebellate rigidity.
What is the difference between Schiff-Sherrington posture and the other two?
Schiff-Sherrington is related to spinal injury, while the other two are related to brain pathology.
What is decerebrate rigidity characterized by?
Extension and increased tone in all four limbs with extension of the head and neck.
What is decerebellate rigidity characterized by?
Increased extensor tone in the thoracic limbs, flexed pelvic limbs, and extension of the neck and head.
What is the aim of gait evaluation?
To identify affected limbs and classify changes as incoordination, weakness, or lameness.
What other abnormalities can be observed during gait evaluation?
Leaning, falling, or circling tendencies can be seen.
Where should gait evaluation be performed?
In a place where the animal can walk freely, ideally on a non-slippery surface.
What is ataxia?
Lack of coordination that can arise from peripheral nerve or spinal cord lesions.
What are the two types of ataxia?
Proprioceptive or sensory ataxia, and vestibular ataxia.
What are the clinical signs caused by cerebellar lesions?
Altered mental status, variably affected cranial nerves, tetra/hemi paresis/plegia, affected proprioception, normal to increased muscle tone, possible cervical hyperaesthesia, cardiac/respiratory abnormalities.
What are the functions of the brainstem?
Regulatory centers for consciousness, cardiovascular system, and breathing; links cerebral cortex to spinal cord through ascending and descending motor pathways; contains 10 pairs of cranial nerves (III to XII).
What are the clinical signs caused by brainstem lesions?
Altered mental status, possibly abnormal cranial nerves, tetra/hemi paresis/plegia, affected proprioception, normal to increased muscle tone, possible cervical hyperaesthesia, cardiac/respiratory abnormalities.
What is the vestibular system responsible for?
Maintaining balance and normal orientation relative to gravitational field of the earth; maintaining position of eyes, neck, trunk, and limbs relative to head movement.
What are the clinical signs of central vestibular syndrome?
Head tilt (ipsilateral/contralateral), spontaneous horizontal/vertical/rotatory nystagmus, variable positional reaction, possibly abnormal mental status.
What are the clinical signs of peripheral vestibular syndrome?
Ipsilateral head tilt, horizontal/rotatory nystagmus, normal positional reaction, normal mental status.
What is the structure of the spinal cord?
Central grey matter with sensory neurons, interneurons, and lower motor neurons; peripheral white matter divided into dorsal, lateral, and ventral funiculi.
How many spinal cord segments are there in dogs and cats?
8 cervical, 13 thoracic, 7 lumbar, 3 sacral, and at least 2 caudal; not all correspond to vertebral bodies.
What is the difference between upper motor neurons and lower motor neurons?
Lower motor neurons are efferent neurons connecting CNS to somatic or visceral muscle; upper motor neurons control and influence lower motor neurons.
What are the clinical signs of lower motor neuron dysfunction?
Flaccid paresis/paralysis, decreased to absent muscle tone, decreased to absent segmental reflexes, rapid and severe neurogenic muscle atrophy.
What are the clinical signs of upper motor neuron dysfunction?
Spastic paresis/paralysis, normal to increased muscle tone, normal to increased segmental reflexes, late and mild disuse muscle atrophy.
What is the motor unit composed of?
The motor unit is composed of the LMN, neuromuscular junction, and muscle fibers.
What are muscle fibers composed of?
Muscle fibers are composed of several hundred myofibrils containing myofilaments.
What is the difference in motor units between muscles responsible for fine movements and muscles responsible for coarse movement?
Muscles responsible for fine movements have small motor units, while muscles responsible for coarse movement have large motor units.
What are the possible neurological examination findings for mental status?
The possible neurological examination findings for mental status are normal.
Which cranial nerves may show abnormalities in the neurological examination?
Possible abnormalities can be found in cranial nerves VII, IX, and X.
What are the possible posture/gait findings in the neurological examination?
Possible findings include flaccid tetraparesis/plegia in posture/gait.
What deficits can be observed in proprioception on affected limbs?
Deficits may be observed on affected limbs in proprioception.
What can be observed in spinal reflexes and muscle tone in affected limbs?
Spinal reflexes and muscle tone may be decreased to absent in affected limbs.
What can be observed in sensation during the neurological examination?
Sensation can be normal or decreased to absent in nociception and sensation.
What other findings can be observed during the neurological examination?
Other findings that may be observed include self-mutilation.
What are the clinical signs caused by neuromuscular lesions?
Clinical signs caused by neuromuscular lesions are variable and depend on the pathology.
What references can be consulted for further information?
References include BSAVA Manual of Canine and Feline Neurology 4th Edition and Handbook of Veterinary Neurology 4th Edition.
Why is information regarding species, age, breed, sex, and coat color important in history taking?
Some conditions have a predilection for certain species, age groups, breeds, and coat colors.
Why is it important to know the animal’s background in history taking?
To identify any previous health conditions or concurrent/systemic problems that may contribute to the neurological signs.
What specific questions should be asked to establish the onset and progression of the condition?
Questions about the nature of onset (acute, insidious, chronic) and progression (improvement, deterioration, wax and waning, paroxysmal).
What terms can be used to describe gait abnormalities?
Weak, wobbly, or lame.
What terms can be used to describe paroxysmal episodes?
Seizure, loss of balance, or collapse.
Why is a thorough physical examination important in neurology?
To identify systemic diseases and concurrent problems that may present with neurological signs.
What is the aim of the neurological examination?
To establish the nature of the condition and the neuroanatomical localisation.
What is the next step after establishing the neuroanatomical localisation?
Formulating a differential diagnosis list.
What does the withdrawal reflex evaluate?
The lumbar intumescence, femoral and sciatic nerves.
What does the patellar reflex evaluate?
The L4-L6 spinal cord segments and femoral nerve.
What does the perineal reflex evaluate?
The S1 to Cd5 and pudendal nerve.
How is the cutaneous trunci reflex performed?
By pinching the skin between T2 and L4-L5.
What muscles contract during the cutaneous trunci reflex?
The cutaneous trunci muscles bilaterally.
In what cases can the cutaneous trunci reflex be lost ipsilaterally?
In cases of caudal brachial plexus lesions.
What is the significance of a lack of a cutaneous trunci reflex?
It has no significance in the absence of other neurological deficits.
What should be tested last during spinal palpation?
The area suspected to be painful.
What is evaluated by conscious response to a painful stimulus?
Nociception.
Why is the evaluation of nociception important?
It assesses the severity of a lesion and its prognosis.
What is the purpose of cranial nerve examination?
To localize intracranial conditions and assess peripheral nerve diseases.
What is the first stage of cranial nerve examination?
Assessment of symmetry.
What are the structures assessed for symmetry in cranial nerve examination?
Masticatory muscles (CN V), ears and lips (CN VII), pupil size (CN II and III), eye position (CN III, IV, and VI), palpebral fissure (CN III or V), and third eyelid (sympathetic nerve or CN V).
How can vision be evaluated in cranial nerve examination?
By leaving the animal to navigate in new surroundings or blindfolding each eye.
How is the palpebral reflex performed?
By touching the medial and lateral canthus of the eyes.
What does the pupillary light reflex involve?
Shining a light in the eyes to cause pupillary constriction.
What is assessed by the menace response?
Blinking in response to a menacing gesture.
When can physiological nystagmus be elicited?
By moving the head from side to side and up and down.
When is pathological nystagmus usually seen?
At rest in cases of pathology.
What are the different directions of pathological nystagmus?
Vertical, horizontal, and rotatory.
What can sometimes make assessing the cutaneous trunci reflex difficult?
Overweight patients.
What are the three divisions of neuromuscular diseases?
The three divisions are peripheral nerve, neuromuscular junction, and muscular pathology.
How many pairs of cranial nerves are there in the peripheral nervous system?
There are 12 pairs of cranial nerves in the peripheral nervous system.
Where are the motor axons located in the nervous system?
Motor axons are located in the ventral horn of the spinal cord or grey matter of the brainstem.
Where are the sensory axons located in the nervous system?
Sensory axons have their cell bodies in the dorsal root ganglion or homologous ganglia of cranial nerves.
What are the components of the neuromuscular junction?
The components are axon terminal, synaptic cleft, and endplate region of a skeletal muscle fiber.
What is the function of the neuromuscular junction?
The neuromuscular junction converts electrical signals to chemical signals and back to electrical signals.
What happens when an action potential reaches the nerve terminal?
The action potential depolarizes the axon, causing calcium channels to open and acetylcholine vesicles to be released.
What is the role of acetylcholine in the neuromuscular junction?
Acetylcholine binds to receptors in the endplate region of skeletal muscle fibers, triggering muscle contraction.
What is the main function of skeletal muscles?
Skeletal muscles function to maintain body posture.
What order is function lost in progressive spinal cord diseases?
The order is proprioception, motor function, bladder function, and nociception.
What are the most important factors for pet owners when it comes to epilepsy treatment?
Drug efficacy and possible side effects.
What is the lifelong commitment required when starting epilepsy medication for pets?
Regular administration and in some cases regular monitoring.
When can the maintenance dose of potassium bromide be started?
After the five loading dose days.
What can be done if the seizures cease before the five days loading is completed?
Start the maintenance dose to try to minimize the side effects.
What is levetiracetam thought to act by modifying?
Calcium-dependent exocytosis of neurotransmitters.
What does levetiracetam bind to?
SV2A pre-synaptic vesicular system.
When is levetiracetam generally used?
As an add-on drug.
When can levetiracetam be used as a first choice?
In certain cases such as in patients with compromised liver function.
What is the loading dose of levetiracetam?
60-90 mg/kg IV once.
When should a blood sample be taken for exclusion of metabolic and toxic causes?
At the time of presentation.
What should be measured prior to increasing the dose of an anti-epileptic drug?
Serum levels of the drug.
When should blood tests be repeated?
A few days after initial presentation.
What should be done if seizures are seen occasionally?
Diazepam or midazolam can be used.
What should be considered if despite drug loading or inability to control further seizures?
A constant rate infusion drug.
How long should a constant rate infusion be maintained?
At least six hours.
How should the dose of diazepam be reduced?
By 50% every 6 hours to avoid withdrawal seizures.
What are the dose and administration requirements for midazolam?
0.2mg/Kg bolus followed by 0.2-0.3mg/Kg/hour in saline.
What is the recommended bolus dose of propofol?
1-2mg/Kg to effect.
What is the definition of status epilepticus?
Continuous seizure activity for longer than 30 minutes or repeat episodes without return to normality within 30 minutes.
What is the definition of cluster seizures?
Two or more seizures within a 24-hour period.
What is the aim of emergency seizure treatment?
To either stop the episode itself or prevent any further seizures from happening.
What can be the consequences of status epilepticus and cluster seizures?
Permanent brain damage or even death, and a higher chance of euthanasia.
What is the aim of immediate control during emergency treatment?
To stop seizure activity and avoid systemic effects.
What is the function of diazepam in immediate control of seizures?
Increases the inhibitory post-synaptic potential, increasing seizure threshold and inhibiting seizure spread.
What is the dose of diazepam for immediate control?
Bolus of 0.5 to 2mg/Kg IV up to 20mg or 1 to 2mg/Kg rectally.
What is the function of midazolam in immediate control of seizures?
Acts as a benzodiazepine alternative to diazepam.
How is midazolam administered for immediate control?
Bolus of 0.2mg/Kg IV or 0.2mg/Kg intranasally.
What is the recommended dose for midazolam CRI during immediate control?
0.3mg/Kg/hour.
What are the systemic effects that need to be controlled during emergency seizure treatment?
Airway, breathing, circulation, and vital parameters.
Why is monitoring of vital parameters important during emergency seizure treatment?
To monitor heart rate, respiratory rate, peripheral pulses, temperature, and avoid complications.
What is the primary aim of anti-epileptic drug therapy during emergency treatment?
To stop seizure activity and prevent further seizures.
What is the loading drug of choice for patients not currently on medication and with no known liver pathology?
Phenobarbitone.
What is the loading dose of Phenobarbitone?
18-24mg/Kg within 24 hours (18mg/Kg in cats).
What is the loading protocol for severe cases of status epilepticus?
Initial dose of 12mg/Kg IV followed by two to three injections of 3-4mg/Kg.
What are the side effects of zonisamide in dogs?
The side effects of zonisamide in dogs include sedation, decreased appetite, vomiting, and behavioral changes.
How is zonisamide metabolized in the body?
Zonisamide is metabolized in the liver by hepatic microsomal enzymes.
What is the recommended dose of zonisamide for dogs?
The recommended dose of zonisamide for dogs is 5-10 mg/kg twice daily.
What is the mode of action of zonisamide?
The mode of action of zonisamide is unknown.
What is the recommended dose of gabapentin for seizure management?
The recommended dose of gabapentin for seizure management is 10-20 mg/kg TID.
What is the most common side effect of gabapentin?
The most common side effects of gabapentin are sedation and ataxia.
What is the half-life of zonisamide in dogs?
The half-life of zonisamide in dogs is three to four hours.
What are the possible side effects of zonisamide?
The possible side effects of zonisamide include ataxia, sedation, vomiting, hepatopathy, renal tubular acidosis, and dry eye.
What are the side effects of gabapentin?
The side effects of gabapentin include sedation and ataxia.
Why is zonisamide not widely used in veterinary medicine?
Zonisamide is not widely used in veterinary medicine due to its high cost.
What is the recommended dosing frequency for zonisamide in dogs?
Zonisamide should be given two times daily.
What is the recommended dose of zonisamide in refractory cases?
The recommended dose of zonisamide in refractory cases is 10 mg/kg BID or a 25% reduction in phenobarbitone dose.
How is gabapentin excreted from the body?
Gabapentin is nearly exclusively excreted via the kidneys.
What are the reported side effects of zonisamide in dogs?
The reported side effects of zonisamide in dogs include sedation, decreased appetite, vomiting, and behavioral changes.
What is the recommended dose of zonisamide for dogs already on phenobarbitone?
The recommended dose of zonisamide for dogs already on phenobarbitone is 10 mg/kg BID.
What is the recommended dose of zonisamide for pulse therapy in cluster seizures?
The recommended dose of zonisamide for pulse therapy in cluster seizures is 60-90 mg/kg followed by 20-30 mg/kg given three to four times daily until no seizures are seen for 24 hours.
What are the essential elements of monitoring and supportive care for patients with epilepsy?
Urinary catheter placement, turning, eye and mouth care.
What are some factors that can contribute to treatment failure in epilepsy?
Genetic factors, poor owner compliance, drug discontinuation, inadequate blood levels, inadequate therapy, drug interaction/malabsorption, development of a new condition, incorrect diagnosis.
How can drug discontinuation be avoided in epilepsy treatment?
By assessing owners’ lifestyle and explaining the consequences associated with drug discontinuation.
What can be responsible for breakthrough in seizure control in epilepsy?
Hepatic induction associated with phenobarbitone administration, increase salt uptake and increase bromide clearance in dogs swimming in the sea.
Why is correct identification of a seizure important in epilepsy treatment?
Incorrect therapy can be initiated with no change in the frequency/severity of the events.
What are some recommended references for further reading on epilepsy treatment?
Bateman SW, Parent JM, Charalambous M, Bhatti SFM, Van Ham L, Platt S, Jeffery ND, Tipold A, Siedenburg J, Volk HA, Hasegawa D, Gallucci A, Gandini G, Musteata M, Ives E, Vanhaesebrouck AE, Hardy BT, Patterson EE, Cloyd JM, Moore SA, Munana KR, Papich MG, Platt SR, Randell SC, Scott KC, Chrisman CL, Hill RC, Gronwall RR, Haag M, Podell M, Smeak D, Lord LK, Wagner SO, Sams RA, Zimmermann R, Hülsmeyer V, Gindiciosi B, Palus V, Eminaga S, Villiers E, Bruto Cherubini G, Peters RK, Schubert T, Clemmons R, Vickroy.
What are the recommended monitoring intervals for phenobarbitone therapy?
10-15 days, 45 days, 90 days, 180 days, every six months to yearly thereafter
How should dose adjustments be made for phenobarbitone therapy?
Based on serum levels, not oral dose
In which cases is potassium bromide indicated?
Low initial seizure frequency or liver disease
What are the possible side effects of potassium bromide?
Polyphagia, polyuria, polydipsia, ataxia, weakness, and pancreatitis
How should potassium bromide be administered?
With food to avoid gastrointestinal signs
What should be done in case of suspected potassium bromide overdose?
Immediately reduce the oral dose and administer 0.9% sodium chloride solution if severe
What factors can influence potassium bromide serum levels?
Abrupt dietary changes, exposure to sea water, and certain medications
What is the recommended monitoring interval for potassium bromide?
2 months, 4-6 months, and 6 months to yearly thereafter
What should be considered when changing food or allowing the patient to swim in the sea?
Possible influence on potassium bromide serum levels
What is the recommended starting dose of imepitoin?
10 mg/kg/BID
What are the reported side effects of imepitoin?
Polyphagia, hyperactivity, polyuria, polydipsia, and sedation
Is serum level monitoring required for imepitoin?
No, it is not required
In which cases is the usage of imepitoin contraindicated?
Cases with renal function impairment
What is the main excretion route for levetiracetam?
Unchanged in the urine
What is pleocytosis?
An increased WBC count in cerebrospinal fluid.
How can blood contamination affect CSF interpretation?
It can falsely increase protein level and cell count.
What is albuminocytological dissociation?
Increased protein level with normal total cell count.
What are the abnormal findings associated with albuminocytological dissociation?
Compressive lesions, neoplasia, ischaemic or degenerative myelopathy.
How is lymphocytic pleocytosis characterized?
Increased protein level, >5 WBC/uL with >50% lymphocytes.
What conditions can cause lymphocytic pleocytosis?
Lymphoma, necrotizing non-suppurative meningoencephalitis.
What is mixed cell pleocytosis?
Increased protein level, >5 WBC/uL, mainly a mixture of lymphocytes and mononuclear cells.
What conditions can cause mixed cell pleocytosis?
GME, fungal and protozoal diseases.
