Degenerative Brain Disease

Question 1

Give 3 examples of degenerative brain diseases

Answer 1

1. multiple sclerosis
2. motor neurone disease
3. Parkinson’s disease

Question 2

What is the definition of a degenerative brain disease?

Answer 2

• slowly progressive diseases which stop neurological function
• variable rates of progression

Question 3

What is multiple sclerosis?

Answer 3

• disease of the central nervous system involving the demyelination of axons
  
  • most common CNS disease of the young
  • progressive functional loss

Question 4

What causes multiple sclerosis?

Answer 4

• inflammatory changes resulting in demyelination

Question 5

How does multiple sclerosis present on an MRI?

Answer 5

• white patchy plaques with red areas of inflammatory processes
• areas experiencing inflammation change over time, affecting different parts of the body

Question 6

What is the impact of multiple sclerosis?

Answer 6

• permanent neurological deficit and loss of function
  
  • can occur anywhere containing neurones
  • motor, cognitive, sensory, autonomic

Question 7

What is the aetiology of multiple sclerosis?

Answer 7

• Unknown but thought to have a genetic propensity
  
  • more common in identical twins
  • twins can have different disease levels
  • more common in immediate family members
• susceptibility is potentially acquired during childhood
• potentially a host reaction to an infective agent
• potentially related to vitamin D
  
  • incidence increases further from the equator

Question 8

What are the signs of multiple sclerosis?

Answer 8

• muscle weakness
• visual disturbance
• paraesthesia
  
  • burning/prickling sensation
• autonomic dysfunction
• dysarthria
  
  • difficulty speaking
• pain
• balance and hearing loss

Question 9

What are the symptoms of multiple sclerosis?

Answer 9

• muscle weakness
• spasticity
  
  • indicative of an UMN lesion
• altered reflexes
• tremor
  
  • intention
  • when trying to complete a task
• optic atrophy
  
  • reduced optic nerve conduction speed
  • longer to conduct to occipital lobe
• proprioceptive loss
  
  • issues with limb positioning
• loss of touch
  
  • pain felt but no cause
  • sudden sensation loss

Question 10

How can multiple sclerosis be investigated?

Answer 10

• history and examination
• MRI
  
  • shows location of plaques
  • shows previous inflammation
• CSF analysis
  
  • reduced lymphocytes
  • increased IgG protein
• visual evoked potentials
  
  • reduced after optic neuritis

Question 11

What are the two types of multiple sclerosis?

Answer 11

1. relapsing and remitting
2. primary progressive

Question 12

Describe relapsing and remitting type multiple sclerosis

Answer 12

• acute exacerbations and periods of respite
  
  • damage builds up with each episode
  • stable between episodes
  • often become secondary progressive

Question 13

Describe primary progressive type multiple sclerosis

Answer 13

• slow and steady progressive deterioration
  
  • cumulative neurological damage
  • no exacerbation and remission periods

Question 14

How is multiple sclerosis managed?

Answer 14

• symptomatic management
  
  • management during acute attack
  • symptoms must be present
• antibiotics, antispasmodics, analgesia, steroids
  
  • slow the episodic nature of relapsing and remitting type
  • do not reverse damage
• disease modifying therapies
  
  • may slow some progressive forms
  • cladribine
  • siponomod
  • ocrelizumab
• physiotherapy and occupational therapy
• stem cell transplant
  
  • to reboot the immune system
  • immune system recognition changed
  • risky procedure
  • existing damage not reversed

Question 15

What are the dental considerations of multiple sclerosis?

Answer 15

• limited mobility and psychological disorders
  
  • difficult accessing dental care
  • unable to perform oral hygiene adequately
  • mental health problems common
• treatment under local anaesthetic
  
  • general anaesthetic may hasten damage
• orofacial motor and sensory disturbance
  
  • suspicious in younger patients
  • unexplained loss of motion or sensation
  • refer for MRI immediately
• chronic orofacial pain possible
  
  • may be no cause of pain
• enhanced trigeminal neuralgia risk
  
  • suspicious in younger patients

Question 16

What is motor neurone disease?

Answer 16

• degeneration of the motor neurone in the anterior horns of the corticospinal tracts in the spinal cord
  
  • can affect bulbar motor nuclei (brain stem)
  • progressive disease
  • short lifespan

Question 17

Who is most likely to be diagnosed with motor neurone disease and what is the prognosis?

Answer 17

• 30-60 year olds
• more common in males
• yeah within 3 years of diagnosis

Question 18

What are the signs of motor neurone disease?

Answer 18

• progressive loss of motor function

Question 19

How does motor neurone disease result in death?

Answer 19

• ventilation failure
  
  • impaired ventilation
  • hypoxia
• aspiration pneumonia
  
  • caused by coughing and swallowing
  • protective reflexes of pharynx lost

Question 20

How is motor neurone disease treated?

Answer 20

• no effective treatments

Question 21

What body parts are affected by motor neurone disease?

Answer 21

• limbs
• intercostal muscles
  
  • impaired ventilation
• diaphragm
  
  • impaired ventilation
• motor cranial nerves (CNVII-CNXII)
  
  • swallowing difficulties
  • muscles of facial expression altered

Question 22

What are the main symptoms the patient may notice?

Answer 22

• weakness in ankle or leg
  
  • tripping
  • hard to climb stairs
• slurred speech
  
  • progresses to difficulty swallowing
• weak grip
  
  • dropping things
  • hard to open jars/do up buttons etc.
• muscle cramps and twitches
• weight loss
  
  • limbs become thinner over time
  • muscle bulk is lost
• emotional lability
  
  • crying or laughing at inappropriate situations

Question 23

How is motor neurone disease managed?

Answer 23

• physiotherapy and occupational therapy
  
  • maintain function for as long as possible
• riluzole
  
  • benzothiazole
  • 6-9 month life extension
• aspiration prevention
  
  • PEG tube feed (reduced aspiration risk)
  • reduce salivation (oral bacteria not in lungs)

Question 24

What are the dental aspects of motor neurone disease?

Answer 24

• difficulty accepting dental care
  
  • muscle weakness in head and neck
  • tipping forward of head and drooling
  • oral hygiene ability reduced
• realistic treatment planning
  
  • must think of quality of life
  • complex and long lasting treatments are not necessary
• drooling and swallowing difficulties
  
  • medications used to dry up saliva
  • anticholinergics
  • botox injection into salivary gland

Question 25

What is Parkinson's disease?

Answer 25

- a degenerative disease due to a lack of dopamine in the substantia nigra

Question 26

What are the features of Parkinson's and who does it affect?

Answer 26

- relatively common - disabling - progressive - as disease progresses, dopamine reduced - on scans show dopamine marker lost - usually older people - some versions found in younger patients

Question 27

What causes Parkinson's disease?

Answer 27

- degeneration of dopaminergic neurones in the basal ganglia (substantia nigra) - shortage of dopamine results in difficulty of messages passing from thinking to doing the the brain - slow passage from cortex to cerebellum/brainstem - underlying cause is unknown - repeated head trauma considered

Question 28

What are the clinical signs of Parkinson's disease?

Answer 28

- bradykinesia - slow movement - slow initiation of movement - rigidity - increased muscle tone - joints are stiffer and move in a jerky manner - tremor - slow amplitude - felt in hands, arms and mandible - rest tremor and intentional movement inhibits - can progress from some poor movement to no movement very quickly

Question 29

What are the effects of Parkinson's disease?

Answer 29

- tremor - pain - visuospatial dysfunction - dysphagia - gastrointestinal dysfunction - frequent falls - high cholesterol levels - low urate levels - mild cognitive impairment - postural problems - mobility problems

Question 30

How does Parkinson's disease manifest?

Answer 30

- impaired gait and falls - unsteady walking - impaired use of upper limbs - mask like face - reduced function of facial expression muscles - swallowing problems - voluntary muscles of pharynx affected - loss of cognitive function - non-motor changes are particularly distressing

Question 31

What is the treatment for Parkinson's disease?

Answer 31

- physiotherapy and occupational therapy - maintain function at as high a level for as long as possible - maximise living ability with remaining function - dopamine - levodopa - initially effective but dose must be continually increased - side effects become intolerable - dopamine analogues - mimic effect of dopamine - tablets - promipexole, selegiline - injection - apomorphine (subcutaneous) - infusion - duodena (direct to gut) - some medications cause abnormal compulsions - gambling addiction

Question 32

How is Parkinson's disease treated?

Answer 32

- surgery - stereotactic surgery - deep brain stimulation with electrodes - allows some return of function - stem cell transplant - aims to deposit dopamine into substantia nigra

Question 33

What are the dental aspects of Parkinson's disease?

Answer 33

- difficulty accepting treatment - tremor at rest of body - mouth opening often stops tremor - increased time needed to comply with requests - dry mouth - anticholinergic effects of drugs - water and saliva substitutes - drug interactions - check for Parkinson's and dental drug interactions