Neuro Flashcards
1
Q
What are the two main components of the brain?
A
The cerebral cortex and the cerebellum.
2
Q
How many major lobes is the cerebrum divided into?
A
Four major lobes.
3
Q
What connects the right and left hemispheres of the brain?
A
The corpus callosum.
4
Q
What does grey matter in the brain primarily consist of?
A
Neuronal cell bodies.
5
Q
What does white matter in the brain consist of?
A
Myelinated neurons.
6
Q
What are the four major lobes of the cerebrum?
A
- Frontal lobe
- Temporal lobe
- Occipital lobe
- Parietal lobe
7
Q
What is the role of the primary motor cortex?
A
Control of voluntary motor functions.
8
Q
Where is Broca’s Area located?
A
In the posterior segment of the third frontal gyrus in the dominant hemisphere.
9
Q
What is the function of Wernicke’s Area?
A
Comprehension and understanding of language.
10
Q
What happens when Broca’s Area is damaged?
A
Inability to find words and speech that is not fluent.
11
Q
What is the function of the arcuate fasciculus?
A
Links Broca’s and Wernicke’s Areas.
12
Q
What are the four major ventricles of the brain?
A
- Lateral ventricles
- Third ventricle
- Fourth ventricle
- Central canal
13
Q
How much cerebrospinal fluid (CSF) is produced per day?
A
800 ml.
14
Q
What do the internal carotid arteries supply?
A
Oxygenated blood to the anterior brain circulation.
15
Q
What is the function of the basilar arteries?
A
Supply the brainstem and cerebellum.
16
Q
What is the significance of the blood-brain barrier (BBB)?
A
Regulates entry of molecules into the brain.
17
Q
Which cranial nerve is responsible for the sense of smell?
A
Olfactory nerve (I).
18
Q
What is the function of the optic nerve?
A
Vision.
19
Q
What does the oculomotor nerve control?
A
Eye movement and pupil size.
20
Q
What is the role of the human eye’s cornea?
A
Converges light onto the retina.
21
Q
What are the main components of the anterior segment of the human eye?
A
- Cornea
- Iris
- Lens
22
Q
Where do light impulses travel after being detected by photoreceptors?
A
Along the optic nerve.
23
Q
What is the significance of the optic chiasm?
A
Where the optic nerves from each eye join.
24
Q
What type of visual deficit is caused by an optic chiasm lesion?
A
Bitemporal hemianopia.
25
What is the length of the spinal cord?
40-50 cm.
26
What is the function of the corticospinal tract?
Transmits motor signals from the brain to the spinal cord.
27
What is the role of the premotor cortex?
Plans movements.
28
What type of neurons are the anterior horn cells?
Lower motor neurons (LMN).
29
What is the function of the extrapyramidal system?
Modulates lower motor neuron excitation, primarily for reflexes and posture.
30
What type of receptors are involved in pain and temperature sensation?
Nociceptors.
31
What is the role of the dorsal columns in sensory function?
Transmits vibration and proprioception sensation.
32
Fill in the blank: The _______ segment of the spinal cord signifies the end of the spinal cord.
filum terminale.
33
What does the lumbosacral plexus supply?
All of the lower limb motor and sensory function.
34
What is the function of the radial nerve?
Supplies motor function to elbow extensors and wrist extensors.
35
Which cranial nerve is associated with balance?
Vestibulocochlear nerve (VIII).
36
What is the main function of the trigeminal nerve?
Facial sensation and mastication.
37
What sensory modalities follow the dorsal columns?
Vibration and proprioception sensation
## Footnote
These modalities are transmitted through specific pathways in the nervous system.
38
Where do axons decussate in the pathway for vibration and proprioception?
At the medulla
## Footnote
This is crucial for the contralateral processing of sensory information.
39
What is the role of tertiary neurons in the sensory pathway?
They radiate to the cortex from the thalamus
## Footnote
This final relay is essential for conscious perception of sensory stimuli.
40
What are the key sites for localising a lesion in the nervous system?
* Anterior horn cell within the spinal cord
* Nerve root - motor only
* Nerve plexus - motor and sensory
* Single or multiple peripheral nerves
* Neuromuscular junction
* Muscle fibres
## Footnote
Identifying the lesion site is crucial for diagnosis and treatment.
41
What can cause a nerve lesion?
* Demyelination
* Axonal degeneration
## Footnote
Both conditions can significantly affect nerve function.
42
What is involved in Nerve Conduction Studies (NCS)?
Stimulating a peripheral nerve at multiple sites and receiving the electrical stimulation at a distal receptor
## Footnote
This helps assess the integrity and function of peripheral nerves.
43
When should nerve conduction studies be performed after an injury?
At least 7 days following an injury
## Footnote
This allows for accurate assessment of nerve function.
44
What is the significance of F-Wave in nerve studies?
Detection of retrograde impulse that travels to cord and returns down nerve
## Footnote
This can indicate the health of the nerve pathways.
45
What does prolonged distal latency in nerve conduction studies indicate?
Demyelination
## Footnote
This is a key finding in diagnosing nerve injuries.
46
What is the Sunderland Classification used for?
To classify nerve injuries based on prognosis
## Footnote
This helps in predicting recovery outcomes.
47
What are the classical signs of Third Nerve Palsy?
* Down and out eye
* Mydriasis (dilated pupil)
* Complete ptosis
## Footnote
These signs are indicative of oculomotor nerve dysfunction.
48
What can cause Third Nerve Palsy?
* Vascular - posterior communicating artery aneurysm or hemorrhage
* Brainstem lesion - demyelinating, tumor or vascular
* Cavernous sinus - thrombosis or tumor compression
* Superior orbital fissure - compressive lesions
## Footnote
Understanding the causes can guide treatment options.
49
What is the function of the Abducens nerve?
Controls lateral eye gaze
## Footnote
Damage to this nerve results in inability to move the eye towards temporal visual fields.
50
Which cranial nerve is affected in Sixth Nerve Palsy?
Abducens nerve
## Footnote
This nerve's dysfunction is characterized by specific eye movement limitations.
51
What is a common cause of Seventh Nerve Palsy?
Bell's palsy
## Footnote
This is a lower motor neuron pattern affecting facial muscles.
52
What differentiates Bell's palsy from upper motor neuron lesions?
Involves the forehead muscles
## Footnote
Upper motor neuron lesions typically spare the forehead due to bilateral innervation.
53
What is Ramsay-Hunt Syndrome caused by?
Reactivation of varicella zoster in the geniculate ganglion of the seventh cranial nerve
## Footnote
This condition presents with vesicles in the external auditory canal.
54
What are the presenting symptoms of Bulbar Palsy?
* Dysphagia
* Dysarthria with nasal speech
* Dribbling
## Footnote
These symptoms arise from lower motor neuron dysfunction affecting cranial nerves.
55
Name a common cause of Bulbar Palsy.
* Vascular events
* Motor neuron disease
* Guillain-Barre Syndrome
* Tumor of the medulla
* Myasthenia gravis
## Footnote
Identifying the cause is crucial for management.
56
What is characteristic of Pseudobulbar Palsy?
Upper motor neuron weakness of cranial nerves IX, X, XI, and XII
## Footnote
Symptoms include dysphagia and dysarthria with an increased gag reflex.
57
What is the common site of entrapment for the median nerve?
Carpal tunnel
## Footnote
This condition can lead to significant sensory and motor deficits.
58
What is the result of a radial nerve lesion?
* Wrist drop
* Weak elbow extension
* Sensory loss over the anatomical snuff box
## Footnote
These symptoms indicate compromised function of the radial nerve.
59
What is the typical presentation of foot drop?
Inability to dorsiflex the foot
## Footnote
This is often due to lesions at the L5 level or peroneal nerve pathology.
60
What is the epidemiology of Myasthenia Gravis?
Relatively rare autoimmune condition with a prevalence of approximately 10 per 100,000 people
## Footnote
This condition affects females more than males, typically starting in the 4th decade.
61
What is the primary pathology in Myasthenia Gravis?
Autoantibodies attack nicotinic acetylcholine receptors at the neuromuscular junction
## Footnote
This leads to decreased muscle excitation and contractility.
62
What is the most well-described sign of Myasthenia Gravis?
Inducible motor weakness, classically ptosis
## Footnote
This symptom is key in diagnosing the condition.
63
What is the first-line treatment for Myasthenia Gravis?
Pyridostigmine
## Footnote
This acetylcholinesterase inhibitor helps improve muscle strength.
64
What is Lambert-Eaton Syndrome typically associated with?
Small cell lung cancer
## Footnote
This condition involves autoantibodies to voltage-gated calcium channels.
65
What is the primary effect of reducing calcium flux in the context of acetylcholine release?
Decrease acetylcholine release
66
What symptom predominates in myasthenia gravis?
Limb weakness causing proximal myopathy
67
How common is ocular, bulbar, and respiratory involvement in myasthenia gravis?
Rare
68
What imaging technique is recommended for excluding a thymoma?
CT imaging
69
What is the surgical intervention indicated for myasthenia gravis?
Surgical thymus removal
70
What is the first-line treatment for symptomatic myasthenia gravis?
Pyridostigmine
71
What is the onset time for Pyridostigmine?
Within 10 minutes
72
What must be avoided in patients with myasthenia gravis?
Drugs that worsen myasthenia (anaesthetics, aminoglycosides, beta-blockers, chloroquine, quinine)
73
Name a class of drugs used for immunosuppression in myasthenia gravis.
Glucocorticoids, azathioprine, mycophenylate, cyclosporine
74
What is the mechanism of immunosuppression in myasthenia gravis?
To reduce circulating autoantibodies
75
What is the role of intravenous immunoglobulin in myasthenia gravis?
Bind circulating autoantibodies
76
What does plasma exchange do in the context of myasthenia gravis?
Removes circulating autoantibodies by removing the entire plasma
77
What is the most common cause of early mortality in myasthenia gravis?
Respiratory failure during myasthenic crisis
78
What is the connection between inflammatory myopathies and malignancy?
There is a strong correlation with coexisting malignancy
79
What are the classic symptoms of polymyositis?
Painful proximal muscle weakness and atrophy
80
What antibodies are associated with dermatomyositis?
Anti-synthetase, Anti-Jo, Anti-signal recognition peptide (Anti-SRP)
81
What is a distinguishing feature of dermatomyositis?
Heliotrope rash around the eyes
82
What is the characteristic muscle biopsy finding in inclusion body myositis?
Inclusions of plaques in rimmed vacuoles within muscle fibres
83
What is the risk of rhabdomyolysis in people using statins?
1 in 10,000 people
84
What is the common cause of statin-induced muscle injury?
Rhabdomyolysis
85
What is the primary mechanism of antibody-mediated statin-induced muscle injury?
Formation of antibodies to HMG-CoA Reductase
86
What are the clinical signs of Guillain-Barré Syndrome?
Rapidly progressing, ascending and symmetrical lower motor neuron weakness
87
What is the typical progression of symptoms in Guillain-Barré Syndrome?
Progress to maximal severity over two weeks, plateau, then improve
88
What is the most common preceding infection associated with Guillain-Barré Syndrome?
Campylobacter jejuni
89
What are the key findings in cerebrospinal fluid analysis for Guillain-Barré Syndrome?
High protein concentrations, normal cell counts
90
What is the management for Guillain-Barré Syndrome?
Intravenous Immunoglobulin (IVIG) and Plasma Exchange (PLEX)
91
What is a poor prognostic indicator in Guillain-Barré Syndrome?
Advanced age, extent of symptoms, bulbar involvement
92
What differentiates chronic inflammatory demyelinating polyneuropathy (CIDP) from Guillain-Barré Syndrome?
Symptoms persist for longer than 8 weeks without improvement
93
What is the first-line treatment for CIDP?
Glucocorticoids
94
What is the common cause of peripheral neuropathy in diabetes?
Diabetes is the most common cause
95
What is a typical presentation of diabetic peripheral neuropathy?
Sensory neuropathy involving paraesthesia, impaired proprioception, and vibration
96
What is a common presenting complaint in multifocal motor neuropathy?
Wrist drop
97
What antibodies are commonly tested in multifocal motor neuropathy?
Anti-GN1 in 80% of cases
98
What is multiplex and what conditions can cause it?
Multiplex typically presents with multiple affecting peripheral nerve lesions and is more likely as a result of a systemic condition such as myeloma, amyloidosis, diabetes or vasculitis.
## Footnote
These systemic conditions can lead to polyneuropathies.
99
What are polyneuropathies and their common causes?
Polyneuropathies are symmetrical and usually axonal, caused by inherited conditions, connective tissue disease, vasculitis, metabolic issues, or toxins.
## Footnote
Common inherited conditions include Charcot Marie Tooth, and metabolic issues may involve uraemia, diabetes, hypothyroidism, or vitamin B deficiency.
100
What is Charcot-Marie-Tooth disease?
The most common hereditary motor-sensory neuropathy, characterized by varying forms, usually resulting in demyelination of neurons.
## Footnote
It follows an autosomal dominant inheritance pattern, primarily linked to a duplication on chromosome 17.
101
What are the classical findings in Charcot-Marie-Tooth disease?
Classical findings include distal limb weakness with foot drop, hammer toe, pes cavus, lower leg changes (champagne bottle sign), hand and forearm weakness, and distal sensory changes.
## Footnote
There is no cranial nerve, respiratory muscle, or bulbar involvement.
102
How is Charcot-Marie-Tooth disease diagnosed?
Diagnosis is confirmed by clinical examination and a positive family history. Genetic testing may be performed in the absence of a definitive diagnosis.
## Footnote
Sural nerve biopsy can show chronic demyelination and remyelination, forming the 'onion bulb' sign.
103
What is the typical age of onset for motor neuron disease?
Typical age of onset is mid-50s.
## Footnote
The condition has a low incidence affecting 2 per 100,000 people per year.
104
What percentage of motor neuron disease cases are inherited?
Only 5-10% of cases are inherited from affected parents.
## Footnote
The hereditary forms often involve mutations in specific genes, such as the SOD gene.
105
What are the major subtypes of motor neuron disease?
There are four major subtypes of motor neuron disease, categorized based on clinical findings. Bulbar involvement carries a poor prognosis.
## Footnote
Each subtype has differing prognostic implications.
106
What are common clinical features of motor neuron disease?
Clinical features include mixed upper and lower motor neuron weakness, muscle atrophy, fasciculations, and bulbar weakness with dysarthria.
## Footnote
Late-stage signs may include progressive bulbar dysfunction and cognitive impairment.
107
What is the role of riluzole in the management of motor neuron disease?
Riluzole has a modest effect in slowing disease progression and improving survival by approximately 3 months.
## Footnote
It works by inhibiting glutamate release and prolonging GABA effects.
108
What are common differential diagnoses for motor neuron disease?
Differential diagnoses include multifocal motor neuropathy, Guillian Barre Syndrome, chronic inflammatory demyelinating polyneuropathy, and brain or spinal cord lesions.
## Footnote
These conditions can present with similar lower or upper motor neuron signs.
109
Fill in the blank: The classical sign of Charcot-Marie-Tooth disease includes _______.
distal limb weakness with foot drop.
110
True or False: Motor neuron disease has a definitive investigation available for diagnosis.
False.
111
What is the mechanism of action of riluzole?
Inhibition of glutamate release from presynaptic neurons and prolonging GABA effects with synaptic clefts.
## Footnote
This helps decrease glutamate excitotoxicity.
112
What is the typical presentation of motor neuron disease?
Asymmetrical and distal lower motor neuron weakness, with progression to bulbar disease being common.
## Footnote
The disease is rapidly progressive.
113
What is the prevalence of epilepsy in the population before adulthood?
1%
## Footnote
The prevalence increases to 3% over a lifetime.
114
What is the gender predominance in epilepsy cases?
Slight predominance for males
115
What are the two peaks in the bimodal distribution of epilepsy onset?
* Childhood/adolescence
* After the age of 60
116
What increases the risk of adulthood epilepsy?
Febrile seizures as an infant
117
What is the most common cause of epilepsy?
Idiopathic causes
118
List common secondary causes of epilepsy.
* Cerebrovascular accident
* Traumatic brain injury
* Intracranial haemorrhage
* Central nervous system infection
* Brain tumour
119
What are less common secondary causes of epilepsy?
* Infiltrative lesions
* Neurosarcoidosis
* Autoimmune encephalitis
* Vascular malformations
120
What are common reversible causes of seizures?
* Sleep deprivation
* Drug/alcohol withdrawal
121
Define epilepsy.
Generally requires 2 or more unprovoked seizures occurring more than 24 hours apart.
122
What characterizes an acute symptomatic seizure?
Occurs in the setting of a systemic or brain insult.
123
What are the criteria for resolving epilepsy?
* Past applicable age for age-dependent epilepsy syndrome
* Seizure-free for 10 years and off medications for the last 5 years
124
What triggers seizure activity?
The stimulus must exceed the 'seizure threshold'.
125
What is the ILAE 2017 Classification of Seizure Types?
Includes basic and expanded versions.
126
What are characteristics of Focal Aware seizures?
* No loss of consciousness
* Aura sensations
* Motor phenomena may be present
127
What is Mesial Temporal Sclerosis?
Condition with sclerosis of the hippocampal area leading to temporal lobe epilepsy.
128
What is the typical duration of Focal Aware seizures?
Last 2-5 minutes on average.
129
Describe Absence seizures.
* Brief loss of consciousness
* No awareness of the episode
* Lasts about 5 seconds
130
What are Atonic seizures also known as?
Drop attacks
131
What occurs during a Generalised Tonic-Clonic seizure?
* Complete loss of consciousness
* Tonic phase followed by clonic phase
132
What is Todd's paralysis?
Post-ictal paralysis that generally resolves without treatment.
133
What is Lennox-Gastaut Syndrome?
Childhood onset of different variants of seizure activity with significant intellectual impairment.
134
What is the typical age of onset for Benign Rolandic Epilepsy?
Typically occurs in childhood and ceases in adolescence.
135
What is Juvenile Myoclonic Epilepsy (JME)?
Onset in childhood/teenage years characterized by involuntary muscle contractions.
136
What is a characteristic EEG finding in Childhood Absence Epilepsy?
3Hz spike waves
137
What investigations should be performed for the first GTC seizure?
* Electrolyte abnormalities
* Toxin ingestion
* Drug contributions
* Infection
138
What is the role of EEG in the investigation of seizures?
An abnormal EEG supports a diagnosis of epilepsy.
139
What is the first-line treatment for GTC seizures?
Benzodiazepines
140
What is the treatment for status epilepticus?
Admission to ICU, intubation, and aggressive anticonvulsant therapy.
141
What is the effectiveness of single drug therapy for unprovoked seizures?
Effective in 50% of people
142
What are common drug targets for anticonvulsants?
* Sodium channel blockade
* Increase GABA effect
* Calcium channel blockade
143
What should be monitored in pregnant women taking lamotrigine?
Drug levels
144
What is the risk of epilepsy in children born to parents with the disorder?
Increased risk
145
What lifestyle considerations should be made for those with epilepsy?
* Avoid high-risk activities
* Driving restrictions
* Water safety
146
What should relatives and friends of epilepsy patients be taught?
First aid for seizures
147
What is the significance of a normal EEG after a seizure?
It does not exclude a diagnosis of epilepsy.
148
Which anticonvulsants are considered relatively safe during pregnancy?
Otrigine and levetiracetam
## Footnote
These medications require drug level monitoring.
149
What is a significant risk associated with carbamazepine during pregnancy?
Linked to birth defects in the first trimester
## Footnote
Carbamazepine is not recommended for pregnant women.
150
Which anticonvulsants should be avoided during pregnancy?
Sodium valproate, phenytoin, and phenobarbital
## Footnote
These medications are considered teratogenic.
151
What is essential for protecting the fetus from seizure-related hypoxia during pregnancy?
Continuing anticonvulsant therapy with the safest drug combinations
## Footnote
This is necessary if the benefits outweigh the risks.
152
What is the relationship between parental epilepsy and the risk of epilepsy in children?
Increased risk of epilepsy in children born to parents with the disorder
153
What effect do sodium valproate and carbamazepine have on weight?
Both increase weight
## Footnote
This can lead to poor adherence in certain populations.
154
What is the mechanism of action for sodium valproate?
Sodium channel blockade
## Footnote
It is used for GTC, absence, and partial seizures.
155
What are the adverse effects of sodium valproate?
* Nausea
* Hepatotoxicity
* Pancreatitis
* Not safe, teratogenic
156
What type of seizures is phenytoin primarily used for?
Partial seizures and GTC as a second-line treatment
## Footnote
It is also used in status epilepticus.
157
What are the adverse effects of phenytoin?
* GI disturbance
* Cerebellar toxicity
* Stevens-Johnson syndrome
* Not safe, teratogenic
158
What is the mechanism of action for levetiracetam?
SV2A receptor binding and sodium channel blockade
## Footnote
It is used for partial and GTC seizures as a second-line treatment.
159
What are the potential adverse effects of levetiracetam?
* Somnolence
* Agranulocytosis
* CYP450 induction
* Stevens-Johnson syndrome
* Safe, Category C
160
What is the mechanism of action for carbamazepine?
Sodium channel blockade
## Footnote
It is used for partial and generalized seizures.
161
What are the adverse effects of carbamazepine?
* Stevens-Johnson syndrome
* Safe, Category C
162
What is the mechanism of action for phenobarbital?
GABA mediator
## Footnote
It is used for all seizures except absence.
163
What are the adverse effects of phenobarbital?
* Sedation
* CYP450 induction
* Not safe, teratogenic
164
What type of seizures do benzodiazepines treat?
Generalized seizures
## Footnote
They are associated with dependence and tolerance.
165
What is the primary mechanism of action for topiramate?
Sodium channel blockade and GABA enhancement
## Footnote
It is used for partial and generalized seizures.
166
What are the adverse effects of topiramate?
* Neurotoxicity
* Nephrolithiasis
* Not safe, teratogenic
167
What is the definition of status epilepticus?
Seizure activity for >5 minutes or successive seizures without return to usual self in between
168
What is the initial treatment for status epilepticus?
Basic life support
169
What is the gold standard investigation for optic neuritis?
Visual Evoked Response Assessment
170
What percentage of patients with clinically isolated syndrome (CIS) will develop MS?
Approximately 50%
171
What is the significance of oligoclonal bands in MS?
Presence indicates a strong likelihood of conversion to MS
## Footnote
70% of CIS patients have oligoclonal bands.
172
What are common symptoms of Multiple Sclerosis?
* Visual disturbances
* Transverse myelitis
* Focal limb motor or sensory abnormalities
* Cerebellar features with ataxia
* Bladder dysfunction
173
What is the mechanism of action for interferon beta in MS treatment?
Affects the balance of pro- and anti-inflammatory cytokines in the CNS
174
What is a common adverse effect of glatiramer?
Local skin injection reactions and flu-like illness
175
What is the mechanism of action for dimethyl fumarate?
Activates nuclear receptor factor 2 to protect neurons from oxidative stress
176
What is the most common autoimmune condition affecting the central nervous system?
Multiple Sclerosis
177
What is the relationship between UV exposure and Multiple Sclerosis?
Lower UV exposure is linked to higher relapse rates
## Footnote
Vitamin D supplementation does not reduce the risk of MS.
178
What is fampridine, and what is its proposed benefit?
A novel drug targeting exposed potassium channels on demyelinated neurons; may improve walk speed
179
What is Progressive Multifocal Leukoencephalopathy (PML), and what causes it?
Caused by reactivation of latent JC Virus in the brain
## Footnote
Risks include AIDS and previous immunosuppression.
180
What is the cause of PML?
Reactivation of latent John Cunningham (JC) Virus with the brain
181
What are the risks associated with PML?
* AIDS
* CSF JC-Virus PCR positivity
* Previous immunosuppression
* Treatment with Natalizumab > Dimethyl Fumarate > Alemtuzumab > Fingolomod
* Can occur with Rituxumab
182
How is PML diagnosed?
MRI showing disseminated hyperintensity
183
What is the management approach for PML?
* Cessation of all immunosuppressants
* Consideration of plasma exchange
184
What are poor prognostic factors for PML?
* Older age of onset
* Not relapsing-remitting subtype
* Frequency of relapse
* Short period between relapse
* Recovery not meeting baseline after relapse
185
What is the overall mortality rate for PML compared to the average population?
Increased
186
What are common symptoms experienced by MS sufferers?
* Depression
* Suicide rates significantly increased
* Fatigue
* Hypersomnolence
* Cognitive impairment
* Bladder and bowel dysfunction
* Neuropathic pain
* Spasticity
187
What is the epidemiology of Huntington's Disease?
Rare genetic disorder affecting 5 per 100,000 people
188
At what age do symptoms of Huntington's Disease typically present?
Between 30-50 years of age
189
What genetic risk is associated with Huntington's Disease?
* Huntington gene is found on chromosome 4
* Specific number of trinucleotide CAG repeats within the gene
* Risk of disease if CAG repeats exceed 36
190
What inheritance pattern is most common for Huntington's Disease?
Autosomal dominant
191
What is 'anticipation' in the context of Huntington's Disease?
Increased number of CAG repeats from affected males leading to earlier onset and more severe disease
192
What are the initial symptoms of Huntington's Disease?
Subtle personality and cognitive changes
193
What is the classical sign of Huntington's Disease?
Chorea
194
What is the average life expectancy after onset of Huntington's Disease symptoms?
10-20 years
195
What are common causes of death in Huntington's Disease patients?
* Aspiration pneumonia
* Cardiovascular disease
* Suicide
196
What is the epidemiology of Creutzfeldt-Jakob Disease (CJD)?
Very rare disorder affecting 1 per 1,000,000 people
197
What are the major forms of Creutzfeldt-Jakob Disease?
* Sporadic
* Familial
* Acquired
* Variant CJD
198
What is the pathophysiology of CJD?
* Abnormal prion proteins invade the brain
* Cause misfolding of normal prion proteins
* Result in irreversible neuronal damage
199
What is the most common symptom of CJD?
Dementia
200
What diagnostic tests can be used for CJD?
* Lumbar puncture for 14-3-3 protein
* Electroencephalopathy for slow wave pattern
* MRI for caudate and putamen hyperintensity
201
What is the management approach for CJD?
Palliative measures
202
What is the average survival for patients with Multiple System Atrophy?
Around 5 years
203
What are the initial symptoms of Multiple System Atrophy?
* Akinesia
* Rigidity
* Cerebellar dysfunction
* Autonomic nervous system failure
204
What is the average survival for patients with Progressive Supranuclear Palsy?
Around 7 years
205
What are common symptoms of Progressive Supranuclear Palsy?
* Impaired mobility
* Visual symptoms
* Bulbar dysfunction
* Frontal and executive dysfunction
206
What is Spinocerebellar Ataxia?
An umbrella term involving different distinct subtypes with progressive loss of cerebellar function
207
What genetic inheritance patterns are associated with Spinocerebellar Ataxia?
* Autosomal dominant
* Autosomal recessive
* X-linked
208
What is the primary feature of Spinal Muscular Atrophy?
Significant muscular atrophy and weakness
209
What is Nusinersen?
An intrathecal medication for spinal muscular atrophy that causes alternative splicing of SMN2 gene
210
What is the presentation of Progressive Bulbar Palsy?
Dysarthria and difficulty chewing foods
211
What is the presentation of Pseudobulbar Palsy?
* Dysarthria
* Dysphagia
* Stiff, spastic tongue
* Exaggerated jaw jerk and gag reflex
212
What is the most common pathophysiology of Parkinson's Disease?
Progressive cellular death affecting dopamine-secreting neurons
213
What are Lewy Bodies?
Eosinophilic, intracytoplasmic inclusions with neurons in Parkinson's Disease
214
What is the mean age of onset for Parkinson's Disease?
60 years of age
215
What is the role of the cerebral motor cortex and extra-pyramidal neurons in movement?
Inhibition of the motor cortex and extrapyramidal movements prevents unwanted movement
216
What happens in Parkinson's Disease (PD) regarding the basal ganglia?
Loss of basal ganglia dopaminergic neurons reduces thalamic inhibition within the extra-pyramidal system, allowing unwanted movements
217
What is the most common and specific clinical sign of Parkinson's Disease?
Bradykinesia
218
Describe the tremor associated with Parkinson's Disease.
Slow frequency, 4-6Hz resting tremor, described as 'pill rolling', initially unilateral
219
What is rigidity in the context of Parkinson's Disease?
Increased muscle tone causing difficulty moving, leading to 'cogwheel rigidity'
220
What is postural instability in Parkinson's Disease?
Balance disorder involving vestibular systems, proprioception, and sensory loss
221
List classical symptoms and signs of Parkinson's Disease.
* Festinating gait with reduced arm swing
* Micrographia
* Cognitive impairment with loss of executive function
* Depression
* Sleep disturbance
* Constipation
* Hallucinations
222
What are the differential diagnoses for Parkinson's Disease?
* Drug-induced Parkinsonism
* Vascular Parkinsonism
* Progressive supranuclear palsy
* Multiple system atrophy
* Corticobasal degeneration
* Wilson's Disease
223
What is the standard initial treatment for Parkinson's Disease?
Levodopa, often in combination with a decarboxylase inhibitor (carbidopa)
224
What are common adverse effects of Levodopa?
* Nausea
* Dyskinesias
* Tolerance
225
What are dopamine agonists and give examples?
Drugs that cause direct activation of dopamine receptors. Examples: pramipexole, bromocriptine, rotigotine
226
What is the function of monoamine oxidase inhibitors in Parkinson's Disease?
Inhibition of MAO-B enzymes decreases the metabolism of remaining dopamine in the basal ganglia
227
What is the role of COMT inhibitors in Parkinson's Disease treatment?
Inhibiting catechol-O-methyltransferase reduces peripheral levodopa breakdown, increasing its effects
228
What is the mechanism of action of Amantadine in Parkinson's Disease?
Unknown mechanism, with minimal evidence for its use in PD
229
What is the prognosis of Parkinson's Disease?
PD is progressive despite optimal medical treatment, with a common progression to Lewy Body Dementia
230
What is the average time from diagnosis to death in Parkinson's Disease with optimal treatment?
Approximately 15 years
231
What is essential tremor and its epidemiology?
The most common movement disorder affecting 6% of the population, with a bimodal distribution
232
What are the clinical features of essential tremor?
Tremor is not present at rest, becomes apparent on intention/action, frequency is 4-10Hz
233
What is the first-line treatment for essential tremor?
Beta blockers such as propranolol
234
What are some drugs associated with tremor?
* Bronchodilators/beta-agonists (e.g., salbutamol)
* Pseudoephedrine
* Theophylline toxicity
* Lithium toxicity
* Neuroleptics
235
What are the four classical mechanisms causing ischaemic stroke?
* Thrombosis
* Thromboembolism
* Hypoperfusion
* Venous occlusion
236
What is the leading modifiable risk factor for stroke?
Hypertension
237
What is the impact of transient ischaemic attack on stroke risk?
High risk of stroke (10% in 1 week, 20% in 3 months)
238
What is the male predominance in stroke epidemiology?
Men are more likely to have strokes, but affected women have worse outcomes
239
What are common causes of venous occlusion leading to stroke?
* Thrombophilias
* Pregnancy
* Intracranial infections
* Malignancy
240
What can cause large watershed areas of infarction?
Olic hypotension
## Footnote
Olic hypotension is a rare cause of ischemic stroke compared to thrombosis or thromboembolism.
241
What are common predispositions for olic hypotension?
* Severe shock
* Intraoperative hypotension
242
What can cause venous occlusion leading to ischemia?
* Thrombosis
* Tumour obstruction of venous sinuses
243
What happens to blood flow through smaller vessels during venous occlusion?
It decreases due to pressure changes, causing ischemia
244
What are some causes of venous thrombosis?
* Thrombophilias
* Pregnancy
* Intracranial infections
* Malignancy
245
What does the TOAST classification of ischemic stroke include?
* Large artery atherosclerosis
* Cardioembolism
* Small vessel occlusion
* Stroke of other determined aetiology
* Stroke of undetermined aetiology
246
What characterizes a transient ischemic attack (TIA)?
Symptoms typical of a stroke spontaneously resolve within 24 hours
247
What is the risk associated with TIA?
Extremely high risk of recurrence of symptoms and major ischemic stroke
248
What is a common presenting complaint associated with TIA?
Amaurosis fugax
249
What causes amaurosis fugax?
Small retinal artery emboli passing through the ipsilateral internal carotid artery
250
What are the two major methods for classifying true ischemic stroke?
* Identifying the affected cerebral vessel and consequences
* The Oxford Classification
251
What are the requirements for a Total Anterior Circulation Infarct (TACI)?
* Higher centre dysfunction
* Homonymous hemianopia
* Unilateral motor and sensory deficits
252
What causes a Total Anterior Circulation Infarct (TACI)?
Lesion in the internal carotid artery (ICA) or proximal middle cerebral artery (MCA)
253
What are the requirements for a Partial Anterior Circulation Infarct (PACI)?
Two of three clinical features including:
* Higher centre dysfunction
* Homonymous hemianopia
* Motor and sensory deficits
254
What causes a Partial Anterior Circulation Infarct (PACI)?
Lesion in the anterior cerebral artery (ACA) or distal MCA
255
What is a Lacunar Infarct (LACI)?
Symptoms vary greatly depending on the affected small territory
256
What are the five classical LACI syndromes in order of prevalence?
* Pure motor hemiparesis
* Ataxic hemiparesis
* Dysarthria
* Pure sensory
* Mixed motor-sensory
257
What does the FAST acronym stand for in stroke recognition?
* Face droop
* Arm weakness
* Speech changes
* Time to call an ambulance
258
How quickly do neurons become ischemic after cessation of blood supply?
Within 60 seconds
259
What is the infarct core?
The central area of infarcted tissue that dies
260
What is the penumbra in stroke pathology?
Area of vulnerable tissue under hypoxic stress that is potentially salvageable
261
What occurs as time passes after a stroke?
The infarct core grows and collateral blood supply to the penumbra fails
262
What is the National Institute of Health Stroke Scale (NIHSS)?
A validated clinical assessment tool to determine likelihood of stroke and severity of disability
263
What is the maximum score on the NIHSS?
42
264
What is crucial to exclude before considering thrombolysis?
Intracranial hemorrhage
265
What is the main medication used for intravenous thrombolysis?
Tissue plasminogen activator (tPA)
266
What is the half-life of tPA?
5 minutes
267
What is the time window for effective thrombolysis treatment?
Within 4.5 hours of symptom onset
268
What are the contraindications for thrombolysis?
* History of intracranial hemorrhage
* Age >18 years
* Known intracranial AV malformation
* Clear onset of symptoms within 4.5 hours
* Known intracranial malignancy
* Non-Contrast CT showing no evidence of hemorrhage
269
What is the risk of intracranial hemorrhage with thrombolysis?
3% risk
270
What should be considered for patients with severe unilateral carotid artery stenosis?
Carotid endarterectomy between 4-14 days after stroke event
271
What is the benefit of a multidisciplinary stroke unit?
Evidence suggests improved outcomes for stroke patients
272
What is the risk of recurrence of stroke within 5 years?
15%
273
What percentage of patients experience permanent disability after ischemic stroke?
One-third
274
What types of hemorrhagic stroke are included in the broad group of pathologies?
* Intraparenchymal hemorrhage
* Intraventricular hemorrhage
* Subarachnoid hemorrhage
* Subdural hemorrhage
* Epidural hemorrhage
275
What is the prognosis for intraparenchymal hemorrhage compared to ischemic stroke?
Markedly worse
276
What is cerebral amyloid angiopathy?
A condition that increases the risk of hemorrhage, especially in Alzheimer's Disease
277
What is the prognosis for haemorrhagic stroke compared to ischaemic stroke?
The prognosis is markedly worse than ischaemic stroke.
278
What are the two major forms of haemorrhage?
Cerebral amyloid angiopathy and CADASIL.
279
What condition increases the risk of cerebral amyloid angiopathy?
Alzheimer's Disease.
280
What imaging technique typically shows multifocal microbleeds in patients with amyloid angiopathy?
MRI.
281
What is CADASIL?
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.
282
What are the common symptoms of CADASIL?
* Progressive cognitive impairment
* Migraine
* Mood disorder
* Recurrent subcortical infarcts.
283
At what age does CADASIL typically onset?
Usually in the 40s.
284
What genetic testing is used to diagnose CADASIL?
Testing of the NOTCH3 gene.
285
What is the most common cause of intracranial haemorrhage?
Hypertensive haemorrhage.
286
What are poor prognostic factors for intracranial haemorrhage?
* Haematoma size
* Neurological deficits
* Reduced level of consciousness
* Interventricular extension
* Obstructive hydrocephalus
* Anticoagulation use.
287
Should blood pressure be lowered if significantly elevated in intracranial haemorrhage?
Yes, but there is no improvement in outcomes with intensive blood pressure lowering.
288
What typically causes intraventricular haemorrhage?
* Trauma
* Aneurysm rupture
* Arteriovenous malformations
* Tumours.
289
What is a clinical symptom suggesting subarachnoid haemorrhage (SAH)?
Sudden onset 'thunderclap' headache.
290
What procedure may reveal red blood cells or xanthochromia in SAH?
Lumbar puncture.
291
When is lumbar puncture most sensitive for detecting SAH?
12 hours after onset of symptom.
292
How can SAH be distinguished from a traumatic tap?
By comparing RBC in the 1st and 4th tube.
293
What imaging should be performed first for suspected SAH?
CT imaging.
294
What is the characteristic CT finding in a subdural haematoma (SDH)?
'Crescent-shaped' haematoma abutting the skull.
295
What is the typical cause of an extradural haematoma (EDH)?
Trauma.
296
What imaging shows a 'convex-shaped' haematoma in EDH?
CT imaging.
297
What is a common symptom of cerebral venous sinus thrombosis?
Persistent, severe headache.
298
What are risk factors for cerebral venous sinus thrombosis?
* Females on hormone replacement therapy or contraception
* Pregnancy
* Prothrombotic state or thrombophilia
* Infection
* Malignancy.
299
What is the first line investigation for cerebral venous sinus thrombosis?
CT or MR venography.
300
Fill in the blank: The most common hereditary cerebral angiopathy is _______.
[CADASIL]
