Neuro Flashcards
1
Q
Define Huntington’s
A
• Autosomal dominant trinucleotide repeat disease (CAG repeat on chr4) characterised by progressive chorea and dementia, typically commencing in middle age
2
Q
Aetiology Huntington’s
A
- Expanded CAG repeat at N-terminus of gene that codes for huntingtin protein
- Results in toxic gain of function causes atrophy and neuronal loss of striatum and cortex
- Autosomal dominant earlier age of onset with each successive generation
3
Q
• Early mild symptoms o Lability o Dysphoria (a state of unease or generalised dissatisfaction with life) o Irritability o Incoordination o Fidgeting o Clumsiness o Mental inflexibility o Anxiety o Develops into dementia
• Later stages o Rigid o Involuntary, jerky, dyskinetic movements often accompanied by grunting and dysarthria – CHOREA o Dementia o Fits o Akinetic o Bed-bound o Death
A
Huntington’s
4
Q
Investigations Huntington’s
A
• Diagnosis is often clinical
• Genetic Analysis
o Diagnostic if there are > 39 CAG repeats in the HD gene
o Reduced penetrance leads to an intermediate number of CAG repeats
• Imaging
o Brain MRI or CT may show symmetrical atrophy of the striatum and butterfly dilation of the lateral ventricles
5
Q
Define Myasthenia gravis
A
• Chronic autoimmune disorder of post-synaptic membrane of NMJ in skeletal muscle producing weakness.
6
Q
Aetiology Myasthenia gravis
A
• Antibodies against nicotinic acetylcholine receptor which interferes with neuromuscular transmission via depletion of post-synaptic receptor sites
• Lambert-Eaton Syndrome – paraneoplastic subtype of MG caused by autoantibodies against pre-synaptic calcium channels, leading to impairment of ACh release
o Can be paraneoplastic (small cell lung cancer) or autoimmune
• MG is associated with other AI conditions (eg. pernicious anaemia)
7
Q
• Muscle weakness that worsens with repetitive use/end of day – fatigability
o Order of muscle weakness: extraocular bulbar face neck limb girdle trunk
• Occular symptoms
o Dropping eyelids
o Diplopia (double vision)
• Bulbar symptoms
o Facial paresis (myasthenic snarl)
o Dysarthria (speech disorder)
o Dysphagia (difficulty swallowing)
- Proximal limb weakness
- Shortness of breath
A
Myasthenia gravis
8
Q
Investigations Myasthenia gravis
A
• Serum acetylcholine receptor antibody analysis
o Result above a certain point for given assay
• Muscle specific tyrosine kinase antibodies
o Positive in 70% of generalised MG
• Serial pulmonary function tests
o Low FVC and NIF (negative inspiratory force)
9
Q
Define Meningitis
A
• Inflammation of the leptomeningeal (pia and arachnoid mater) coverings of the brain, most commonly due to infection
• Immune response to infection causes cerebral oedema raising ICP, causing 2 effects:
o Herniation
o Raised ICP + systemic hypotension ↓ cerebral perfusion
10
Q
Aetiology Meningitis
A
• Bacterial o Neonates ♣ Group B streptococci ♣ E. coli ♣ Listeria monocytogenes
o Children
♣ Haemophilus influenza
♣ Nseisseria meningitides
♣ Streptococcus pneumoniae
o Adults
♣ Neisseria meningitides
♣ Streptococcus pneumoniae
♣ Tuberculosis
o Elderly
♣ Streptococcus pneumoniae
♣ Listeria monocytogenes
• Viral o Human enteroviruses o HSV 1 & 2 o Mumps o VZV o HIV
• Fungal o Cryptococcus (common cause of meningitis in HIV patients)
• Others
o Aseptic meningitis (not due to microbes)
o Mollaret’s meningitis (recurrent benign lymphocytic meningitis)
• RISK FACTORS o Close communities (e.g. college halls) o For bacterial: being under 5 or over 60 yrs o Male o Immunosuppressed o Basal skull fractures o Mastoiditis o Sinusitis o Inner ear infections o Alcoholism o Immunodeficiency
11
Q
o Severe headache o Leg pain o Cold hands and feet o Abnormal skin o Neck stiffness o Photophobia o Fever o Irritability/altered mental state o ↓ consciousness o Vomitting
o Photophobia o Neck stiffness o Kernig's Sign o Brudzinski's Sign o Pyrexia o Tachycardia o Hypotension o Skin rash o Altered mental state
A
Meningitis
12
Q
Investigations meningitis
A
• Bloods
o U&Es, FBC (low WCC = immunocompromised – needs help), LFT, glucose, coagulation screen
o Two sets of blood cultures (as well as throat swabs, rectal swabs)
• Imaging
o CT scan - exclude mass lesion or raised ICP before LP
o Other contraindications for LP: suspected intracranial mass lesion, focal signs, papilloedema, trauma, middle ear pathology, major coagulopathy
• Lumbar Puncture – usually done after CT but if GCS 15, no symptoms of raised ICP and no focal neurology: can be done without CT to save time. o Measure opening pressure – 7-18cm CSF is normal, in meningitis may be >40 o Send CSF for MC&S, Gram stain, protein, glucose, virology and lactate o Bacterial meningitis: ♣ Cloudy CSF ♣ High neutrophils ♣ High protein ♣ Low glucose o Viral (‘aseptic’) meningitis – for this, also do CSF PCR ♣ Clear CSF ♣ High lymphocytes ♣ High protein ♣ Normal glucose o TB meningitis: ♣ Fibrinous CSF ♣ High lymphocytes ♣ High protein ♣ Low glucose
13
Q
Management meningitis
A
• IMMEDIATE IV Antibiotics (before LP)
o First choice: 3rd generation cephalosporin (e.g. cefotaxime or ceftriaxone)
o If >55 yrs, add ampicillin too (for Listeria)
o Blind: GIVE IM BENZYLPENICILLIN IF IN GP. If allergic to this: ceftriaxone
• Dexamethasone IV
o Given shortly before or with the first dose of antibiotics
o Associated with a reduced risk of complications
• Then, if no signs of high ICP: do LP
• Resuscitation
o Manage in ITU
o Notify public health services
14
Q
Complications meningitis
A
- Septicaemia
- Shock
- DIC
- Renal failure
- Seizures
- Peripheral gangrene
- Cerebral oedema
- Cranial nerve lesions
- Cerebral venous thrombosis
- Hydrocephalus
- Waterhouse-Friderichsen Syndrome (bilateral adrenal haemorrhage caused by severe meningococcal infection)
15
Q
Raised ICP
A
- ↑ in volume of contents inside the cranium
- Can be mass effect, oedema or obstruction to fluid outflow
- Normal ICP in adults is <15mmHg
16
Q
Aetiology raised ICP
A
- Primary or metastatic tumours
- Head injury
- Haemorrhage
- Infection – meningitis, encephalitis, brain abscess
- Hydrocephalus
- Cerebral oedema
- Status epilepticus
17
Q
• Headache: worse on coughing and leaning forwards, worse in morning
• Vomiting
• Altered GCS – drowsiness, irritability, coma
• History of trauma
Poor vision
- Altered GCS
- Falling pulse and rising BP (Cushing’s response)
- Cheyne-Stokes respiration – progressively deeper and sometimes faster breathing followed by a gradual decrease that results in a temporary stop in breathing - cycle repeats
- Pupil changes – constriction first, later dilatation
- Reduced visual acuity
- Peripheral visual field loss
- Papilloedema – unreliable sign but venous pulsation at the disc may be absent
A
Raised ICP
18
Q
Investigations raised ICP
A
- U&E, FBC, LFT, glucose, serum osmolality, clotting, blood culture
- Consider toxicology screen
- CXR – any source of infection may lead to abscess
- CT head
- Consider LP if safe – measure opening pressure
19
Q
Define Horner’s
A
• Condition resulting from disruption of sympathetic nerves supplying the face resulting in triad of:
o Partial Ptosis – eye lid drooping
o Miosis – pupillary constriction
o Anhydrosis – ipsilateral loss of sweating
o (and enopthalmos – sunken eye)
20
Q
Aetiology Horner’s
A
• Caused by disruption of sympathetic fibres
• Causes – disruption to nerves can be @ different locations:
o Brainstem: demyelination, vascular disease, stroke
o Cord: syringomyelia
o Thoracic outlet: Pancoast’s tumour (apical lung tumour)
o On the sympathetic’s trip on the internal carotid artery into the skull (carotid artery dissection)
o At the orbit
21
Q
- Inability to open eye fully on affected side
- Loss of sweating
- Facial flushing
- Orbital pain/headache
• Ptosis
• Miosis
• Anhydrosis
Enopthalmos
A
Horner’s
22
Q
Investigations Horner’s
A
• Investigations are directed towards figuring out the underlying cause • CXR - apical lung tumour • CT/MRI - cerebrovascular accidents • CT angiography - dissection
23
Q
Management Horner’s
A
- Horner’s syndrome is a sign not a disease in itself
- So, the management depends on the cause (e.g. management for carotid dissection is very different to management of apical lung tumours)
24
Q
Define MS
A
• Inflammatory demyelinating disease of the CNS – discrete plaques of demyelination occur at multiple CNS sites, from T-cell mediated immune response
• Types
o Relapsing-remitting MS
♣ Commonest form
♣ Clinical attacks of demyelination with poor healing inbetween attacks
o Clinically Isolated Syndrome
♣ Single clinical attack of demyelination
♣ Attack itself doesn’t count as MS
♣ 10-50% progress to MS
o Primary Progressive MS
♣ Steady accumulation of disability with No relapsing remitting pattern
o Marburg Variant
♣ Severe fulminant variant of MS leading to advanced disability or death within weeks
25
Aetiology MS
• Unknown
• Autoimmune basis with potential environmental trigger in genetically susceptible individuals
• Immune-mediated damage to myelin sheaths results in impaired axonal conduction
• Risk factors
o EBV exposure
o Prenatal Vit D levels
26
```
• Varies depending on the site of inflammation
• Usually monosymptomatic
• Optic Neuritis (COMMONEST)
o Unilateral deterioration of visual acuity and colour perception
o Pain on eye movement
o Rapid loss of central vision
• Sensory
o Pins and needles
o Numbness
o Burning
• Motor
o Limb weakness
o Spasms
o Stiffness
o Heaviness
• Autonomic
o Urinary urgency
o Hesitancy
o Incontinence
o Impotence
• Psychological/cognitive
o Depression
o Psychosis
o Amnesia
o Reduced executive functioning
• Sexual
o Erectile dysfunction
o Anorgasmia
• GI
o Swallowing disorders
o Constipation
• Cerebellum
o Trunk and limb ataxia
o Intention tremor
o Scanning speech falls
• Early on, relapses then remits to full recovery. With time, remissions are incomplete so disability accumulates
• Uhthoff's Sign - worsening of neurological symptoms as the body gets overheated from hot weather, exercise, saunas, hot tubs etc.
• Lhermitte's Sign - an electrical sensation that runs down the back and into the limbs when the neck is flexed
```
• Optic neuritis
o Impaired visual acuity
o Loss of coloured vision
• Visual Field Testing
o Central scotoma (if optic nerve is affected)
• Scotoma = a blind spot in the normal visual field
o Field defects (if optic radiations are affected)
• Relative Afferent Pupillary Defect (RAPD)
• Internuclear Ophthalmoplegia
o Lateral horizontal gaze causes failure of adduction of the contralateral eye
o Indicates lesion of the contralateral medial longitudinal fasciculus
• Sensory
o Paraesthesia
• Motor
o UMN signs
• Cerebellar
o Limb ataxia (intention tremor, past-pointing, dysmetria)
o Dysdiadochokinesia
o Ataxic wide-based gait
o Scanning speech
MS
27
Investigations MS
• Diagnosis is based on the finding of two or more CNS lesions with corresponding symptoms, separated in time and space - McDONALD CRITERIA
• Lumbar Puncture
o Microscopy - exclude infection/inflammatory causes
o CSF electrophoresis shows unmatched oligoclonal bands
• MRI Brain, Cervical and Thoracic Spine (with gadolinium) – shows lesions
o Plaques can be identified
o Gadolinium enhancement shows active lesions
• Evoked Potentials
o Visual, auditory and somatosensory evoked potentials may show delayed conduction velocity
28
Define neurofibromatosis
```
• Autosomal dominant genetic disorder affecting cells of neural crest origin, resulting in development of multiple neurocutaneous tumours
• Type 1 Neurofibromatosis (von Recklinghausen’s disease)
o Characterised by:
♣ Peripheral and spinal neurofibromas
♣ Multiple café au lait spots
♣ Freckling (axillary/inguinal)
♣ Optic nerve glioma
♣ Lisch nodules (on iris)
♣ Skeletal deformities
♣ Phaeochromocytomas
♣ Renal artery stenosis
```
```
• Type 2 Neurofibromatosis
o Characterised by:
♣ Schwannomas (often bilateral vestibular schwannomas i.e. acoustic neuromas)
♣ Meningiomas
♣ Gliomas
♣ Cataracts
```
29
Aetiology Neurofibromatosis
• Associated with multiple mutations in tumour suppressor genes NF1 (type 1) and NF2 (type 2)
30
• Positive family history (however, 50% are caused by new mutations)
```
• Type 1
o Skin lesions
o Learning difficulties (40%)
o Headaches
o Disturbed vision (due to optic gliomas)
o Precocious puberty (due to lesions of the pituitary gland from an optic glioma involving the chiasm)
- Cafe au lait macules
Freckling in armpit/groin
Lisch nodules
```
```
• Type 2
o Hearing loss
o Tinnitus
o Balance problems
o Headache
o Facial pain
o Facial numbness
Few/no skin lesions
```
Neurofibromatosis
31
Investigations neurofibromatosis
• Full body examination for skin lesions
• Ophthalmological assessment
• Audiometry
• MRI brain and spinal cord - for vestibular schwannomas, meningiomas and nerve root neurofibromas
• Skull X-ray (sphenoid dysplasia in NF1)
Genetic testing
32
Define MS
• Inflammatory demyelinating disease of the CNS – discrete plaques of demyelination occur at multiple CNS sites, from T-cell mediated immune response
• Types
o Relapsing-remitting MS
♣ Commonest form
♣ Clinical attacks of demyelination with poor healing inbetween attacks
o Clinically Isolated Syndrome
♣ Single clinical attack of demyelination
♣ Attack itself doesn’t count as MS
♣ 10-50% progress to MS
o Primary Progressive MS
♣ Steady accumulation of disability with No relapsing remitting pattern
o Marburg Variant
♣ Severe fulminant variant of MS leading to advanced disability or death within weeks
33
Aetiology MS
• Unknown
• Autoimmune basis with potential environmental trigger in genetically susceptible individuals
• Immune-mediated damage to myelin sheaths results in impaired axonal conduction
• Risk factors
o EBV exposure
o Prenatal Vit D levels
34
```
• Varies depending on the site of inflammation
• Usually monosymptomatic
• Optic Neuritis (COMMONEST)
o Unilateral deterioration of visual acuity and colour perception
o Pain on eye movement
o Rapid loss of central vision
• Sensory
o Pins and needles
o Numbness
o Burning
• Motor
o Limb weakness
o Spasms
o Stiffness
o Heaviness
• Autonomic
o Urinary urgency
o Hesitancy
o Incontinence
o Impotence
• Psychological/cognitive
o Depression
o Psychosis
o Amnesia
o Reduced executive functioning
• Sexual
o Erectile dysfunction
o Anorgasmia
• GI
o Swallowing disorders
o Constipation
• Cerebellum
o Trunk and limb ataxia
o Intention tremor
o Scanning speech falls
• Early on, relapses then remits to full recovery. With time, remissions are incomplete so disability accumulates
• Uhthoff's Sign - worsening of neurological symptoms as the body gets overheated from hot weather, exercise, saunas, hot tubs etc.
• Lhermitte's Sign - an electrical sensation that runs down the back and into the limbs when the neck is flexed
```
• Optic neuritis
o Impaired visual acuity
o Loss of coloured vision
• Visual Field Testing
o Central scotoma (if optic nerve is affected)
• Scotoma = a blind spot in the normal visual field
o Field defects (if optic radiations are affected)
• Relative Afferent Pupillary Defect (RAPD)
• Internuclear Ophthalmoplegia
o Lateral horizontal gaze causes failure of adduction of the contralateral eye
o Indicates lesion of the contralateral medial longitudinal fasciculus
• Sensory
o Paraesthesia
• Motor
o UMN signs
• Cerebellar
o Limb ataxia (intention tremor, past-pointing, dysmetria)
o Dysdiadochokinesia
o Ataxic wide-based gait
o Scanning speech
MS
35
Investigations MS
• Diagnosis is based on the finding of two or more CNS lesions with corresponding symptoms, separated in time and space - McDONALD CRITERIA
• Lumbar Puncture
o Microscopy - exclude infection/inflammatory causes
o CSF electrophoresis shows unmatched oligoclonal bands
• MRI Brain, Cervical and Thoracic Spine (with gadolinium) – shows lesions
o Plaques can be identified
o Gadolinium enhancement shows active lesions
• Evoked Potentials
o Visual, auditory and somatosensory evoked potentials may show delayed conduction velocity
36
Define neurofibromatosis
```
• Autosomal dominant genetic disorder affecting cells of neural crest origin, resulting in development of multiple neurocutaneous tumours
• Type 1 Neurofibromatosis (von Recklinghausen’s disease)
o Characterised by:
♣ Peripheral and spinal neurofibromas
♣ Multiple café au lait spots
♣ Freckling (axillary/inguinal)
♣ Optic nerve glioma
♣ Lisch nodules (on iris)
♣ Skeletal deformities
♣ Phaeochromocytomas
♣ Renal artery stenosis
```
```
• Type 2 Neurofibromatosis
o Characterised by:
♣ Schwannomas (often bilateral vestibular schwannomas i.e. acoustic neuromas)
♣ Meningiomas
♣ Gliomas
♣ Cataracts
```
37
Aetiology Neurofibromatosis
• Associated with multiple mutations in tumour suppressor genes NF1 (type 1) and NF2 (type 2)
38
• Positive family history (however, 50% are caused by new mutations)
```
• Type 1
o Skin lesions
o Learning difficulties (40%)
o Headaches
o Disturbed vision (due to optic gliomas)
o Precocious puberty (due to lesions of the pituitary gland from an optic glioma involving the chiasm)
- Cafe au lait macules
Freckling in armpit/groin
Lisch nodules
```
```
• Type 2
o Hearing loss
o Tinnitus
o Balance problems
o Headache
o Facial pain
o Facial numbness
Few/no skin lesions
```
Neurofibromatosis
39
Investigations neurofibromatosis
• Full body examination for skin lesions
• Ophthalmological assessment
• Audiometry
• MRI brain and spinal cord - for vestibular schwannomas, meningiomas and nerve root neurofibromas
• Skull X-ray (sphenoid dysplasia in NF1)
Genetic testing
40
Define MS
• Inflammatory demyelinating disease of the CNS – discrete plaques of demyelination occur at multiple CNS sites, from T-cell mediated immune response
• Types
o Relapsing-remitting MS
♣ Commonest form
♣ Clinical attacks of demyelination with poor healing inbetween attacks
o Clinically Isolated Syndrome
♣ Single clinical attack of demyelination
♣ Attack itself doesn’t count as MS
♣ 10-50% progress to MS
o Primary Progressive MS
♣ Steady accumulation of disability with No relapsing remitting pattern
o Marburg Variant
♣ Severe fulminant variant of MS leading to advanced disability or death within weeks
41
Aetiology MS
• Unknown
• Autoimmune basis with potential environmental trigger in genetically susceptible individuals
• Immune-mediated damage to myelin sheaths results in impaired axonal conduction
• Risk factors
o EBV exposure
o Prenatal Vit D levels
42
```
• Varies depending on the site of inflammation
• Usually monosymptomatic
• Optic Neuritis (COMMONEST)
o Unilateral deterioration of visual acuity and colour perception
o Pain on eye movement
o Rapid loss of central vision
• Sensory
o Pins and needles
o Numbness
o Burning
• Motor
o Limb weakness
o Spasms
o Stiffness
o Heaviness
• Autonomic
o Urinary urgency
o Hesitancy
o Incontinence
o Impotence
• Psychological/cognitive
o Depression
o Psychosis
o Amnesia
o Reduced executive functioning
• Sexual
o Erectile dysfunction
o Anorgasmia
• GI
o Swallowing disorders
o Constipation
• Cerebellum
o Trunk and limb ataxia
o Intention tremor
o Scanning speech falls
• Early on, relapses then remits to full recovery. With time, remissions are incomplete so disability accumulates
• Uhthoff's Sign - worsening of neurological symptoms as the body gets overheated from hot weather, exercise, saunas, hot tubs etc.
• Lhermitte's Sign - an electrical sensation that runs down the back and into the limbs when the neck is flexed
```
• Optic neuritis
o Impaired visual acuity
o Loss of coloured vision
• Visual Field Testing
o Central scotoma (if optic nerve is affected)
• Scotoma = a blind spot in the normal visual field
o Field defects (if optic radiations are affected)
• Relative Afferent Pupillary Defect (RAPD)
• Internuclear Ophthalmoplegia
o Lateral horizontal gaze causes failure of adduction of the contralateral eye
o Indicates lesion of the contralateral medial longitudinal fasciculus
• Sensory
o Paraesthesia
• Motor
o UMN signs
• Cerebellar
o Limb ataxia (intention tremor, past-pointing, dysmetria)
o Dysdiadochokinesia
o Ataxic wide-based gait
o Scanning speech
MS
43
Investigations MS
• Diagnosis is based on the finding of two or more CNS lesions with corresponding symptoms, separated in time and space - McDONALD CRITERIA
• Lumbar Puncture
o Microscopy - exclude infection/inflammatory causes
o CSF electrophoresis shows unmatched oligoclonal bands
• MRI Brain, Cervical and Thoracic Spine (with gadolinium) – shows lesions
o Plaques can be identified
o Gadolinium enhancement shows active lesions
• Evoked Potentials
o Visual, auditory and somatosensory evoked potentials may show delayed conduction velocity
44
Define neurofibromatosis
```
• Autosomal dominant genetic disorder affecting cells of neural crest origin, resulting in development of multiple neurocutaneous tumours
• Type 1 Neurofibromatosis (von Recklinghausen’s disease)
o Characterised by:
♣ Peripheral and spinal neurofibromas
♣ Multiple café au lait spots
♣ Freckling (axillary/inguinal)
♣ Optic nerve glioma
♣ Lisch nodules (on iris)
♣ Skeletal deformities
♣ Phaeochromocytomas
♣ Renal artery stenosis
```
```
• Type 2 Neurofibromatosis
o Characterised by:
♣ Schwannomas (often bilateral vestibular schwannomas i.e. acoustic neuromas)
♣ Meningiomas
♣ Gliomas
♣ Cataracts
```
45
Aetiology Neurofibromatosis
• Associated with multiple mutations in tumour suppressor genes NF1 (type 1) and NF2 (type 2)
46
• Positive family history (however, 50% are caused by new mutations)
```
• Type 1
o Skin lesions
o Learning difficulties (40%)
o Headaches
o Disturbed vision (due to optic gliomas)
o Precocious puberty (due to lesions of the pituitary gland from an optic glioma involving the chiasm)
- Cafe au lait macules
Freckling in armpit/groin
Lisch nodules
```
```
• Type 2
o Hearing loss
o Tinnitus
o Balance problems
o Headache
o Facial pain
o Facial numbness
Few/no skin lesions
```
Neurofibromatosis
47
Investigations neurofibromatosis
• Full body examination for skin lesions
• Ophthalmological assessment
• Audiometry
• MRI brain and spinal cord - for vestibular schwannomas, meningiomas and nerve root neurofibromas
• Skull X-ray (sphenoid dysplasia in NF1)
Genetic testing
48
Define Parkinson's
```
• Neurodegenerative disease of dopaminergic neurones of substantia nigra, characterised by:
o Bradykinesia
o Rigidity
o Resting tremor
o Postural instability
```
49
Aetiology Parkinson's
• Pathophysiology
o Degeneration of dopaminergic neurones projecting from substantia nigra to striatum – due to mitochondrial DNA dysfunction
o Patients are only symptomatic after loss of >70% of dopaminergic neurones
•Sporadic/Idiopathic Parkinson's Disease
o Most COMMON
o Aetiology UNKNOWN
o May be related to environmental toxins and oxidative stress
• Secondary Parkinson's Disease
o Neuroleptic therapy (e.g. for schizophrenia)
o Vascular insults (e.g. in the basal ganglia)
o MPTP toxin from illicit drug contamination
o Post-encephalitis
o Repeated head injury
o Manganese or copper toxicity (Wilson’s disease)
o HIV
There are some familial forms of Parkinson's disease
50
* Insidious onset
* Resting tremor – onset is asymmetrical
* Bradykinesia – slowness of movements
* Postural instability – imbalance or falling noted
* Micrographia – smaller hand writing
* Masked facies – loss of spontaneous facial movement and expressivity
* Hypophonia - ↓ vol of voice
* Subtle: fatigue, constipations, smell ↓, depression, dementia
```
• Tremor
o Pill rolling rest tremor
o 4-6 Hz
o Decreased on action
o Usually asymmetrical
```
• Rigidity
o Lead pipe rigidity of muscle tone
o Superimposed tremor can cause cogwheel rigidity
o Rigidity can be enhanced by distraction
```
• Gait
o Stooped
o Shuffling
o Small-stepped gait
o Reduced arm swing
o Difficulty initiating walking
```
• Postural Instability
o Falls easily with little pressure from the back or the front
```
• Other features
o Frontalis overactivation (leads to furrowing of the brow)
o Hypomimic face
o Soft monotonous voice
o Impaired olfaction
o Tendency to drool
o Mild impairment of up-gaze
```
• Psychiatric
o Depression
o Cognitive problems and dementia (in later stages)
Parkinson's
51
Investigations Parkinson's
• CLINICAL diagnosis
• Levodopa Trial
o Timed walking and clinical assessment after administration of levodopa
• Bloods
o Serum caeruloplasmin - rule out Wilson's disease as a cause of Parkinson's disease
• CT or MRI Brain
o To exclude other causes of gait decline (e.g. hydrocephalus)
• Dopamine Transporter Scintigraphy
o Reduction in striatum and putamen
52
Define Wernicke's
• Presence of neurological Sx caused by biochemical lesions of CNS following exhaustion of Vit B (particularly thiamine/B1) reserves
53
Aetiology Wernicke's
```
• Main cause is chronic alcohol consumption, = in thiamine deficiency by causing:
o Inadequate nutritional thiamine intake
o ↓ thiamine absorption
o Impaired thiamine utilisation by cells
• Other causes of thiamine deficiency:
o Eating disorders
o Malnutrition
o Prolonged vomiting eg. with cemo
o GI malignancy
o Chronic subdural haematoma
o AIDS
o Hypermesis gravidarum
o Thyrotoxicosis
• Thiamine deficiency results in abnormal cellular function in cerebral cortex, hypothalamus and cerebellum
```
54
```
• Vision changes
o Diplopia
o Eye movement abnormalities
o Ptosis
• Loss of memory/cognitive dysfunction
Confusion
```
• Classically defined by a triad of signs:
o Confusion
o Opthalmoplegia (nystagmus, lateral rectus or conjugate gaze palsies)
o Ataxia (wide based gait)
• The patient is usually mentally alert with vocabulary, comprehension, motor skills, social habits and naming ability maintained
• Some show signs suggestive of polyneuropathy
• Reflexes may be decreased
• Abnormal gait and coordination
• Low temperature
• Rapid pulse
• Some may be cachectic
• NOTE: Korsakoff's Psychosis occurs when the condition deteriorates further, leading to the additional symptoms of:
o Amnesia
o Confabulation
Wernicke's encephalopathy
55
Investigations Wernickes
• Diagnosis is mainly based on history and examination
• Possible useful tests:
o FBC (high MCV is a common feature amongst alcoholics)
o U&Es (exclude metabolic imbalances as a cause of confusion)
o LFTs
o Glucose
o ABG (hypercapnia and hypoxia can cause confusion)
o Serum thiamine
o Red cell transketolase activity is decreased – rarely done
• CT head scan may be useful
56
Define hydrocephalus
• Enlargement of the cerebral vestibular system due to accumulation of CSF
• Either due to:
o Too much CSF being produced (rare)
o Blockage in CSF flow
o Insufficient CSF being re-absorbed
• Can be subdivided into obstructive and non-obstructive
o Aka communicating and non-communicating
Hydrocephalus ex vacuo = apparent enlargement of the ventricles as a compensatory change due to brain atrophy
57
Aetiology hydrocephalus
• Abnormal accumulation of CSF in ventricles caused by:
o Obstructive: Impaired outflow of CSF from the ventricular system
♣ Lesions of 3rd and 4th ventricle or cerebral aqueduct
♣ Posterior fossa lesions (eg. tumour) compressing the 4th ventricle
♣ Cerebral aqueduct stenosis
o Non-obstructive: Impaired CSF reabsorption into subarachnoid villi
♣ Tumours
♣ Meningitis
♣ Normal Pressure Hydrocephalus – idiopathic chronic ventricular enlargement. Long white matter tracts are damaged leading to gait and cognitive decline
58
Acute drop in conscious level
Diplopia (due to 6th nerve palsy)
Low GCS
Papilloedema
NEONATES:
Increase head circ
Sunset sign
Obstructive Hydrocephalus
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Investigations hydrocephalus
• CT Head
o FIRST-LINE for detecting hydrocephalus
o May also pick up the cause (e.g. tumour)
• CSF
o From ventricular drain or lumbar puncture
o May indicate pathology (e.g. tuberculosis)
o Check MC&S, protein and glucose
• Lumbar Puncture
o IMPORTANT: contraindicated if raised ICP
o Therapeutic in normal pressure hydrocephalus
