Neurology Flashcards
What is the most common CNS disorder of the young (80:100000)?
Multiple sclerosis
what is MS?
Inflammation causing changes to the myelin sheath around the nerve axons connecting different parts of the brain
Is MS a demyelinating or myelinating condition?
Demyelinating
What group of individuals are likely to have the most severe onset of MS?
Women with 4th decade onset
Which individuals have higher incidence of MS?
Identical twins and immediate family members
The aetiology of MS remains a mystery. Nevertheless, what are the three suspected causes?
- Susceptibility acquired during childhood
- Altered host reactions to an infective agent
- Background genetic/immune factors
What incidence has lead to the suggestion that lack of sunlight and vitamin D may be a factor involved in the aetiology of MS?
Incidence of MS increases the further away from the equator that a person lives
What specific effects can MS have on the brain?
- fatigue
- cognitive changes
- depression
- dizziness and vertigo
What specific effects can MS have on the eyes?
- Blurred vision
- temporary blindness
- seeing dark spots
What specific effects can MS have on the bowl?
- constipation
- diarrhoea
What specific effects can MS have on the bladder?
- frequent urination
- incontinence
What specific effects can MS have on the muscles?
- weakness
- stiffness
- spasms
How will demyelination appear on an MRI scan?
As areas of red (inflammatory change)
What is muscle spasticity?
Abnormal muscle tightness due to prolonged muscle contraction
What is muscle spasticity an indication of?
A motor neurone lesion
What degenerative change, and in what nerve, can be easily measured? (Common test for assessing MS)
The decreased speed of conduction in the optic nerve
What is protracted pain?
Pain that lasts longer than 3-6 months (chronic pain)
What is dysarthria?
Difficulty speaking because muscles used for speech are weak
What are the symptoms of MS?
- muscle weakness
- visual disturbances
- parasthesia
- autonomic dysfunction
- dysarthria
- pain
- balance/hearing loss
what are the signs of MS?
- muscle weakness
- spasticity
- altered reflexes
- intention tremor
- optic atrophy
- Proprioceptive loss
- loss of touch
What is intention tremor?
A tremor during a purposeful motor movement,which worsens before reaching the end point
what is optic atrophy?
Optic nerve shrinkage
what are the 4 main investigations for MS?
- History and examination
- MRI
- CSF analysis
- Visual evoked potentials
What does CSF analysis show if MS is present?
- reduced lymphocytes
- increased IgG protein
What do visually evoked potentials measure?
“Measures the electrical signal generated at the visual cortex in response to visual stimulation”
What would reduced visual evoked potentials suggest?
Optic neuritis
what is optic neuritis?
When inflammation damages the optic nerve
Is MS curable?
No
What are the two types of MS?
- Replacing and emitting type
- Primary progressive type
What type of MS is characterised by acute exacerbations and periods of respite, where damage builds up with each episode?
Relapsing and emitting type
What type of MS is characterised by slow steady progressive deterioration from cumulative neurological damage?
Primary progressive type
What is the symptomatic Management for an acute MS attack?
- antibiotics, antispasmodics, analgesia
- physiotherapy and occupational therapy
What are the names of three drugs that are effective at slowing down the rate at which new lesions occur, making a significant difference to management of MS?
- Cladribine
- Siponomod
- Ocrelizumab
What are the dental considerations of someone who has MS?
- patients may have limited mobility & psychological disorders
- always treat under LA if possible
- orofacial motor and sensory disturbances
- chronic orofacial pain
- enhanced risk of trigeminal neuralgia
Why should patients with MS ideally be treated under LA?
There is a suggestion that giving LA hastens the onset of damage within the brain
In the dental clinic, what is the most key indicator that a patient may have MS?
Orofacial motor and sensory disturbances
What is trigeminal neuralgia?
A type of chronic pain disorder that involves sudden, severe facial pain
What condition is characterised by degeneration of the motor nerves in the anterior horn of the corticospinal tracts, in the spinal cord, and the degeneration of bulbar motor nuclei in the brain?
Motor neurone disease (MND)
What age range is particularly affected by MND?
Patients aged 30-60 years old
What is the usual prognosis of life expectancy for individuals with MND?
Death within 3 years of diagnosis
what is the ratio of males to females with MND?
(M) 2.5:1 (F)
What are the symptoms of MND, which the patient may notice?
- weakness in the ankle or leg
- slurred speech
- a weak grip
- muscle cramps and twitches
- weight loss
- emotional lability (crying out laughing in inappropriate situations)
In MND, what does progressive loss of motor function in the diaphragm lead to?
Impairment of ventilation, which causes hypoxia
Which cranial nerves are most likely affected by MND, which can usually result in difficulties swallowing as well as maintaining facial expression?
CN VII- XII
What are the two consequences of the progressive loss of function from MND which lead to death?
- ventilation failure (type 2 respiratory failure)
- aspiration pneumonia
what medication is suggested to give some individuals with MND 6-9 months life extension?
Riluzole
What treatment measurement is often taken for individuals with MND who are at high risk of aspiration?
Stopping the patient taking food by mouth and directing it into the stomach via a PEG tube
Why do patients with MND need to control rate of salivation?
As saliva could be aspirated, carrying oral bacteria into the lungs
What are the difficulties associated with dental care for patients with MND?
- difficulty to maintain head and neck posture
- realistic treatment planning
- drooling and swallowing difficulties
What drugs are sometimes taken to stop excess salivation for individuals with MND?
- Anticholenergics
- sometimes Botox injections into salivary glands
What condition is characterised by lack of the neurotransmitter,dopamine, in the substantia nigra of the brain?
Parkinson’s disease
what are the three main clinical features of Parkinson’s disease?
- bradykinesia
- Rigidity
- Tremor
what is meant by bradykinesia?
Slowness of movement and speed as movements are continued
When does tremor usually occur in an individual with Parkinson’s disease. At rest or when active?
At rest
- when patient makes intentional movement, tremor will go away
what are the 4 manifestations of Parkinson’s disease?
- impaired gait and falls
- impaired use of upper limbs
- mask-like face
- swallowing problems
What is meant by an impaired gait?
When an individuals walking is unsteady and unusual in its pattern
What is the first-line drug (dopamine precursor) used for the management of Parkinson’s motor symptoms?
Levodopa
What are the 3 forms of dopamine analogues that mimic dopamine in the treatment of Parkinson’s disease? Give examples.
- Tablets (promipexole, selegiline)
- Injections (apomorphine)
- Infusion (duodopa- directly into gut)
what is the main negative side effect of taking dopaminergic drugs?
They can lead to impulsive behaviour such as gambling
what treatment helps individuals with Parkinson’s disease maintain function at a high level for as long as possible?
Physiotherapy and occupational therapy
What are the two potential surgical options for individuals with Parkinson’s disease?
- Stereotactic surgery
- Stem cell transplant (new findings- not implicated as major therapy)
what is stereotactic surgery?
Deep brain stimulation where there is use of 3D techniques to locate electrodes into part of the brain
What are the barriers and difficulties for patients with Parkinson’s disease in receiving dental care?
- difficulty accepting treatment
- access and movement difficulties
- Dry mouth due to anticholenergic drugs
- may be drug interactions as usually on many medications
Is it likely that a patient with Parkinson’s disease will not be able to receive intra-oral care from their dentist due to their tremor?
No. This tremor is at rest, when the patient opens their mouth they will loose the tremor and treatment can progress.
What is a stroke?
Death of brain tissue due to blockage of blood delivering oxygen to tissues in the brain leading to hypoxia
What are the three types of stroke?
- Ischaemic stroke
- Haemorrhagic stroke
- Transient ischaemic attack
What happens during a transient ischaemic attack (TIA’s)?
Rapid loss of function but a rapid recovery of function. Within 24 hours the patient will have recovered all neurological issues.
What acronym is useful to use when there has been suspected stroke and what does it stand for?
FAST.
F- facial drooping?
A- arm weakness?
S- speech difficulty?
T- time?
Why do TIA’s occur?
Thought to occur due to platelet emboli from vessels in the neck. These emboli block the blood flow to the brain tissue causing ischaemia, but are then rapidly removed by the circulation and blood flow is restored before any permanent damage has occurred.
How long does it take most people to recover from a TIA?
30 minutes