Neurology 3 Flashcards

1
Q

What is Mysthenia Gravis?

A

Myasthenia gravis is an autoimmune disorder resulting in insufficient functioning acetylcholine receptors.

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2
Q

Key features of myasthenia gravis

A

The key feature is muscle fatigability - muscles become progressively weaker during periods of activity and slowly improve after periods of rest:
extraocular muscle weakness: diplopia
proximal muscle weakness: face, neck, limb girdle
ptosis
dysphagia

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3
Q

what is associated with myasthenia gravis?

A

thymomas in 15%
autoimmune disorders: pernicious anaemia, autoimmune thyroid disorders, rheumatoid, SLE
thymic hyperplasia in 50-70%

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4
Q

Investigations for Myasthenia gravis?

A

single fibre electromyography: high sensitivity (92-100%)
CT thorax to exclude thymoma
CK normal
antibodies to acetylcholine receptors
positive in around 85-90% of patients
n the remaining patients, about about 40% are positive for anti-muscle-specific tyrosine kinase antibodies
Tensilon test: IV edrophonium reduces muscle weakness temporarily - not commonly used any more due to the risk of cardiac arrhythmia

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5
Q

Management of myasthenic crisis

A

plasmapheresis
intravenous immunoglobulins

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6
Q

What does the fourth cranial nerve supply?

A

The fourth cranial nerve (trochlear nerve) supplies the superior oblique muscle
this muscle is crucial for rotating the eye downward and outward
by innervating the superior oblique muscle, the trochlear nerve enables the eye to look down when it is adducted (moved towards the nose). This movement is particularly important for actions like going downstairs or reading.

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7
Q

What are the features of a 4th nerve palsy?

A

vertical diplopia
classically noticed when reading a book or going downstairs
subjective tilting of objects (torsional diplopia)
the patient may develop a head tilt, which they may or may not be aware of
when looking straight ahead, the affected eye appears to deviate upwards and is rotated outwards

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8
Q

How does an abducens nerve palsy present?

A

Abducens nerve palsy typically presents with horizontal diplopia owing to weakness in the lateral rectus muscle, which impairs abduction of the affected eye. Patients usually exhibit an esotropia (inward deviation of the affected eye) that becomes more pronounced when gazing towards the lesioned side.

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9
Q

How does an oculomotor never palsy present?

A

Oculomotor nerve palsy generally results in ptosis and impaired adduction, elevation and depression of the affected eye, leading to a ‘down-and-out’ resting position. Pupillary involvement may suggest a compressive etiology such as an aneurysm.

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10
Q

What does superior oblique myokymia cause?

A

it causes episodic monocular vertical oscillations rather than constant vertical diplopia. Patients often report sensations akin to ‘quivering’ within their eye

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11
Q

what is MS?

A

Multiple sclerosis is chronic cell-mediated autoimmune disorder characterised by demyelination in the central nervous system.

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12
Q

What are the different subtypes of MS?

A

Relapsing-remitting disease
most common form, accounts for around 85% of patients
acute attacks (e.g. last 1-2 months) followed by periods of remission

Secondary progressive disease
describes relapsing-remitting patients who have deteriorated and have developed neurological signs and symptoms between relapses
around 65% of patients with relapsing-remitting disease go on to develop secondary progressive disease within 15 years of diagnosis
gait and bladder disorders are generally seen

Primary progressive disease
accounts for 10% of patients
progressive deterioration from onset
more common in older people

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13
Q

Patient with MS on Natalizumab and becomes confused - what may be causing new onset confusion?

A

Progressive multifocal leukoencephalopathy (PML) is associated with natalizumab treatment in multiple sclerosis (MS). It is caused by reactivation of the JC virus due to immunodeficiency secondary to natalizumab (it can also occur with a few other MS modifying drug treatments and HIV). The reactivation of the JC virus causes demyelination and the symptoms a patient has depends on the site and extent of the demyelination. The most common symptoms are confusion, behavioural change, ataxia, hemiparesis and visual deficits.

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14
Q

when may anti-epileptics be started after firs seizure?

A

the patient has a neurological deficit
brain imaging shows a structural abnormality
the EEG shows unequivocal epileptic activity
the patient or their family or carers consider the risk of having a further seizure unacceptable4

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15
Q

Management of generalised tonic clonic seizures?

A

males: sodium valproate
females: lamotrigine or levetiracetam
girls aged under 10 years and who are unlikely to need treatment when they are old enough to have children or women who are unable to have children may be offered sodium valproate first-line

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16
Q

Management of focal seizures?

A

first line: lamotrigine or levetiracetam
second line: carbamazepine, oxcarbazepine or zonisamide

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17
Q

Management of abscence siezures?

A

first line: ethosuximide
second line:
male: sodium valproate
female: lamotrigine or levetiracetam
carbamazepine may exacerbate absence seizures

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18
Q

Management of myoclonic seizures?

A

males: sodium valproate
females: levetiracetam

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19
Q

Mangement of tonic or atonic seizures?

A

males: sodium valproate
females: lamotrigine

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20
Q

what may cause an upbeat nystagmus?

A

cerebellar vermis lesions

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21
Q

What may cause a down beart nystamus?

A

Arnold-Chiari malformation

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22
Q

why does raised ICP cause third nerve palsy?

A

Increased pressure within the cranium secondary to the rapid expansion of intracranial haematoma can cause the temporal lobe to herniate through the tentorial notch. This herniation can compress the ipsilateral third cranial nerve, resulting in a dilated pupil, ptosis and ‘down and out’ eye deviation.

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23
Q

what does the facial nerve supply?

A

The facial nerve is the main nerve supplying the structures of the second embryonic branchial arch. It is predominantly an efferent nerve to the muscles of facial expression, digastric muscle and also to many glandular structures. It contains a few afferent fibres which originate in the cells of its genicular ganglion and are concerned with taste.

Supply - ‘face, ear, taste, tear’
face: muscles of facial expression
ear: nerve to stapedius
taste: supplies anterior two-thirds of tongue
tear: parasympathetic fibres to lacrimal glands, also salivary glands

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24
Q

causes of bilateral facial nerve palsy?

A

Causes of bilateral facial nerve palsy
sarcoidosis
Guillain-Barre syndrome
Lyme disease
bilateral acoustic neuromas (as in neurofibromatosis type 2)
as Bell’s palsy is relatively common it accounts for up to 25% of cases f bilateral palsy, but this represents only 1% of total Bell’s palsy cases

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25
causes of unilateral facial nerve palsy?
Lower motor neuron Bell's palsy Ramsay-Hunt syndrome (due to herpes zoster) acoustic neuroma parotid tumours HIV multiple sclerosis* diabetes mellitus Upper motor neurone Stroke ## Footnote upper motor neuron lesion 'spares' upper face i.e. forehead lower motor neuron lesion affects all facial muscles
26
The path of the facial nerve?
Subarachnoid path Origin: motor- pons, sensory- nervus intermedius Pass through the petrous temporal bone into the internal auditory meatus with the vestibulocochlear nerve. Here they combine to become the facial nerve. Facial canal path The canal passes superior to the vestibule of the inner ear At the medial aspect of the middle ear, it becomes wider and contains the geniculate ganglion. - 3 branches: 1. greater petrosal nerve 2. nerve to stapedius 3. chorda tympani Stylomastoid foramen Passes through the stylomastoid foramen (tympanic cavity anterior and mastoid antrum posteriorly) Posterior auricular nerve and branch to posterior belly of digastric and stylohyoid muscle
27
comparison between Neurfibromatosis and tuberous sclerosis
28
Features of herpes simplex encephalitis?
fever, headache, psychiatric symptoms, seizures, vomiting focal features e.g. aphasia peripheral lesions (e.g. cold sores) have no relation to the presence of HSV encephalitis
29
Which lobes are usually affected in HSV encephalitis?
typically affects temporal and inferior frontal lobes
30
Investigations for HSV encephalitis?
CSF: lymphocytosis, elevated protein PCR for HSV CT: medial temporal and inferior frontal changes (e.g. petechial haemorrhages) - normal in one-third of patients MRI is better EEG pattern: lateralised periodic discharges at 2 Hz
31
Treatment for HSV enephalitis?
intravenous aciclovir The prognosis is dependent on whether aciclovir is commenced early. If treatment is started promptly the mortality is 10-20%. Left untreated the mortality approaches 80%
32
MS investigations?
Diagnosis requires demonstration of lesions disseminated in time and space MRI high signal T2 lesions periventricular plaques Dawson fingers: often seen on FLAIR images - hyperintense lesions penpendicular to the corpus callosum CSF oligoclonal bands (and not in serum) increased intrathecal synthesis of IgG Visual evoked potentials delayed, but well preserved waveform
33
What is a TIA?
a new 'tissue-based' definition is now used: a transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without acute infarction.
34
Clinical features of TIA?
The clinical features are similar to those of a stroke, i.e. sudden onset, focal neurological deficit but, rather than persisting, the features resolve, typically within 1 hour. Possible features include unilateral weakness or sensory loss. aphasia or dysarthria ataxia, vertigo, or loss of balance visual problems sudden transient loss of vision in one eye (amaurosis fugax) diplopia homonymous hemianopia
35
Assessment and referral in TIA?
Patients with acute focal neurological symptoms that resolve completely within 24 hours of onset (i.e. suspected TIA) should: be given aspirin 300 mg immediately unless contraindicated assessed urgently within 24 hours by a stroke specialist clinician ## Footnote If a patient presents more than 7 days ago they should be seen by a stroke specialist clinician as soon as possible within 7 days.
36
TIA mimics that require exclusion?
hypoglycaemia intracranial haemorrhage all patients on anticoagulants or with similar risk factors should be admitted for urgent imaging to exclude haemorrhage
37
Should patients with TIA have brain imaging?
Patients with suspected TIA should be assessed by a stroke specialist clinician before a decision on brain imaging NICE NICE recommend that CT brains should not be done 'unless there is clinical suspicion of an alternative diagnosis that CT could detect' an example exception would be when there is a concern about haemorrhage as the patient is taking anticoagulants MRI (including diffusion-weighted and blood-sensitive sequences) is preferred to determine the territory of ischaemia, or to detect haemorrhage or alternative pathologies it should be done on the same day as the specialist assessment if possible
38
Management of TIA?
patients with TIA or minor ischaemic stroke should be given antiplatelet therapy provided there is neither a contraindication nor a high risk of bleeding for patients within 24 hours of onset of TIA or minor ischaemic stroke and with a low risk of bleeding, the following DAPT regimes should be considered: clopidogrel (initial dose 300 mg followed by 75 mg od) + aspirin (initial dose 300 mg followed by 75 mg od for 21 days) followed by monotherapy with clopidogrel 75 mg od ticagrelor + clopidogrel is an alternative if not appropriate for DAPT: clopidogrel 300 mg loading dose followed by 75 mg od should be given proton pump inhibitor therapy should be considered for DAPT
39
what is Bell's Palsy?
Bell's palsy may be defined as an acute, unilateral, idiopathic, facial nerve paralysis. The aetiology is unknown although the role of the herpes simplex virus has been investigated previously. The peak incidence is 20-40 years and the condition is more common in pregnant women.
40
Features of Bells palsy?
lower motor neuron facial nerve palsy → forehead affected in contrast, an upper motor neuron lesion 'spares' the upper face patients may also notice post-auricular pain (may precede paralysis) altered taste dry eyes hyperacusis
41
Management of Bell's palsy?
in the past a variety of treatment options have been proposed including no treatment, prednisolone only and a combination of antivirals and prednisolone there is consensus that all patients should receive oral prednisolone within 72 hours of onset of Bell's palsy there is an ongoing debate as to the value of adding in antiviral medications Antiviral treatments alone are not recommended UpToDate recommends the addition of antivirals for severe facial palsy eye care is important to prevent exposure keratopathy prescription of artificial tears and eye lubricants should be considered If they are unable to close the eye at bedtime, they should tape it closed using microporous tape
42
Follow up for Bell's Palsy?
if the paralysis shows no sign of improvement after 3 weeks, refer urgently to ENT a referral to plastic surgery may be appropriate for patients with more long-standing weakness e.g. several months
43
What is Transient global amnesia?
Transient global amnesia is characterized by the acute onset of anterograde amnesia (the inability to form new memories). The aetiology is unknown, thought to be due to transient ischaemia to the thalamus (in particular the amygdala and hippocampus). Features patients may appear anxious and repeatedly ask the same question episodes are self-limited and resolve within 24 hours
44
What is the mechanism of action of baclofen?
agonist of GABA receptors acts in the central nervous system (brain and spinal cord)
45
what is baclofen used for?
Baclofen is used to treat muscle spasticity in conditions such as multiple sclerosis, cerebral palsy and spinal cord injuries.
46
Risk factors for idiopathic intracranial hypertension?
Risk factors obesity female sex pregnancy drugs combined oral contraceptive pill steroids tetracyclines retinoids (isotretinoin, tretinoin) / vitamin A lithium
47
Features of idiopathic intracrania hyertension?
headache blurred vision papilloedema (usually present) enlarged blind spot sixth nerve palsy may be present
48
Management of idioathic intracranial hypertension?
weight loss whilst diet and exercise are important, medications such as semaglitide and topiramate may be considered by specialists. Topiramate is particularly beneficial as it also inhibits carbonic anhydrase carbonic anhydrase inhibitors e.g. acetazolamide topiramate is also used, and has the added benefit of causing weight loss in most patients repeated lumbar puncture may be used as a temporary measure but is not suitable for longer-term management surgery: optic nerve sheath decompression and fenestration may be needed to prevent damage to the optic nerve. A lumboperitoneal or ventriculoperitoneal shunt may also be performed to reduce intracranial pressure
49
Wha is Facioscapulohumeral muscular dystrophy?
Facioscapulohumeral muscular dystrophy (FSHMD) is an autosomal dominant form of muscular dystrophy. As the name suggests it typically affects the face, scapula and upper arms first. Symptoms typically present by the age of 20 years.
50
Features of Facioscapulohumeral muscular dystrophy?
facial muscles are involved first - difficulty closing eyes, smiling, blowing etc weakness of the shoulder and upper arm muscles abnormal prominence of the borders of the shoulder blades - 'winging' lower limb: hip girdle weakness, foot drop
51
Features of medication overuse headache?
present for 15 days or more per month developed or worsened whilst taking regular symptomatic medication patients using opioids and triptans are at most risk may be psychiatric co-morbidity
52
management of medication overuse headache?
simple analgesics and triptans should be withdrawn abruptly (may initially worsen headaches) opioid analgesics should be gradually withdrawn Withdrawal symptoms such as vomiting, hypotension, tachycardia, restlessness, sleep disturbances and anxiety may occur when medication is stopped
53
causes of SAH?
intracranial aneurysm (saccular 'berry' aneurysms) accounts for around 85% of cases conditions associated with berry aneurysms include hypertension,adult polycystic kidney disease, Ehlers-Danlos syndrome and coarctation of the aorta arteriovenous malformation pituitary apoplexy mycotic (infective) aneurysms
54
Features of SAH
headache usually of sudden-onset ('thunderclap' or 'hit with a baseball bat') severe ('worst of my life') occipital typically peaking in intensity within 1 to 5 minutes there may be a history of a less-severe 'sentinel' headache in the weeks prior to presentation nausea and vomiting meningism (photophobia, neck stiffness) coma seizures ECG changes including ST elevation may be seen this may be secondary to either autonomic neural stimulation from the hypothalamus or elevated levels of circulating catecholamines
55
Investigations for SAH?
Non contrast CT (if done within 6 hours of symptoms onset and is normal consider alternative diagnosis) If CT done after 6 hours and is normal - do an LP at least 12 hours following the onset of symptoms ## Footnote After spontaneous SAH is confirmed, the aim of investigation is to identify a causative pathology that needs urgent treatment: CT intracranial angiogram (to identify a vascular lesion e.g. aneurysm or AVM) +/- digital subtraction angiogram (catheter angiogram)
56
Management of SAH
Supportive - bed rest, analgesia, VTE prophylaxis Vasospasm is prevented using a oral course of nimodipine Intracranial aneurysms are at risk of rebleeding and therefore require prompt intervention, preferably within 24 hours most intracranial aneurysms are now treated with a coil by interventional neuroradiologists, but a minority require a craniotomy and clipping by a neurosurgeon
57
Complications of aneurysmal SAH?
Re-bleeding (most common in the first 12 hours) - if suspected then CT head should be arranged Hyrdocephalus - is temporarily treated with an external ventricular drain (CSF diverted into a bag at the bedside) or, if required, a long-term ventriculoperitoneal shunt vasospasm (also termed delayed cerebral ischaemia), typically 7-14 days after onset ensure euvolaemia (normal blood volume) consider treatment with a vasopressor if symptoms persist hyponatraemia (most typically due to syndrome inappropriate anti-diuretic hormone (SIADH)) seizures
58
Different types of aphasia?
Wernickes aphasia - receptive Broca's aphasia - expressive Conduction aphasia Global aphasia - affects all of the above areas
59
What leads to wernicke's aphasia? What are the symptoms?
Due to a lesion of the superior temporal gyrus. It is typically supplied by the inferior division of the left MCA This area 'forms' the speech before 'sending it' to Broca's area. Lesions result in sentences that make no sense, word substitution and neologisms but speech remains fluent - 'word salad' Comprehension is impaired
60
What leads to Broca's aphasia?
Due to a lesion of the inferior frontal gyrus. It is typically supplied by the superior division of the left MCA Speech is non-fluent, laboured, and halting. Repetition is impaired Comprehension is normal
61
What leads to condection aphasia
Classically due to a stroke affecting the arcuate fasiculus - the connection between Wernicke's and Broca's area Speech is fluent but repetition is poor. Aware of the errors they are making Comprehension is normal
62
What leads to global aphasia?
Large lesion affecting all 3 of the above areas resulting in severe expressive and receptive aphasia May still be able to communicate using gestures
63
What CN does the cavernous sinus contain ?
The cavernous sinus is an intracranial venous structure that contains CN III, IV, V1, V2, and VI. A lesion in this area can affect multiple cranial nerves simultaneously, leading to the clinical presentation seen in this patient.
64
How does superior orbital fissure syndrome present?
Cranial nerve 3, 4, 6 and ophthalmic division of trigeminal. Presents with ophthalmoplegia, fixed dilated pupils, ptosis, loss of corneal reflex. Proptosis is also seen.
65
How does orbital apex syndrome present?
Orbital apex syndrome: Similar to superior orbital fissure syndrome, with addition of optic nerve involvement, so there will be vision loss as well.
66
How does a cavernous sinus lesion present?
Cavernous sinus lesion= Cranial nerve 3, 4, 6 with or without Horners, proptosis and chemosis. Trigeminal nerve involvement is variable - posterior cavernous sinus lesion involves all 3 divisions, middle the first two, and anterior only the first division. Pupillary involvement is also variable - it may be spared.
67
what would a lateral sinus thrombosis lead to?
6th and 7th cranial nerve palsies
68
What would a saggital sinus thrombosis lead to ?
may present with seizures and hemiplegia parasagittal biparietal or bifrontal haemorrhagic infarctions are sometimes seen 'empty delta sign' seen on venography
69
Investigations for venous sinus thrombosis?
MRI venography is the gold standard CT venography is an alternative non-contrast CT head is normal in around 70% of patients D-dimer levels may be elevated
70
decision making for first line drugs in parkinsons?
70
Decision making for second line drugs in parkinsons if a patient continues to have symptoms despite optimal levodopa treatment or has developed dyskinesia?
71
What is Foster Kennedy syndrome?
This syndrome reflects a frontal lobe tumour - leading to ipsilateral optic atrophy and papilloedema of the contralateral optic nerve. The reason for the optic atrophy is as a result of direct damage from the space occupying lesion
72
What is the mechanism of action of procyclidine?
Antimuscarinic
73
when are antimuscarinics used in parkinsons?
now used more to treat drug-induced parkinsonism rather than idiopathic Parkinson's disease help tremor and rigidity
74
How to antimuscararincs work and what are examples?
Block cholinergic receptors e.g. procyclidine, benzotropine, trihexyphenidyl (benzhexol)
75
Paraneoplastic syndromes affecing the nervous system?
Anti-Hu associated with small cell lung carcinoma and neuroblastomas sensory neuropathy - may be painful cerebellar syndrome encephalomyelitis Anti-Yo associated with ovarian and breast cancer cerebellar syndrome Anti-GAD antibody associated with breast, colorectal and small cell lung carcinoma stiff person's syndrome or diffuse hypertonia Anti-Ri associated with breast and small cell lung carcinoma ocular opsoclonus-myoclonus Purkinje cell antibody - peripheral neuropathy in breast cancer Lambert eaton syndrome
76
what is paraneoplastic syndrome?
Paraneoplastic syndrome is a rare disorder that occurs when the body's immune system attacks healthy cells in response to a tumor.
77
What is Anti-hu associated with?
associated with small cell lung carcinoma and neuroblastomas sensory neuropathy - may be painful cerebellar syndrome encephalomyelitis
78
What is Anti-Yo associated with?
associated with ovarian and breast cancer cerebellar syndrome
79
What is anti-GAD associated with?
associated with breast, colorectal and small cell lung carcinoma stiff person's syndrome or diffuse hypertonia
80
What os Anti-Ri associated with?
associated with breast and small cell lung carcinoma ocular opsoclonus-myoclonus
81
what are the different types of MND?
Amyotrophic lateral sclerosis (50% of patients) typically LMN signs in arms and UMN signs in legs in familial cases the gene responsible lies on chromosome 21 and codes for superoxide dismutase Primary lateral sclerosis UMN signs only Progressive muscular atrophy LMN signs only affects distal muscles before proximal carries best prognosis Progressive bulbar palsy palsy of the tongue, muscles of chewing/swallowing and facial muscles due to loss of function of brainstem motor nuclei carries worst prognosis
82
Which type of MND is the most common, which has the best prognosis and which has the worst prognosis?
Most common : Amyotrophic lateral sclerosis Best prog: Progressive muscular atrophy Worst prog: Progressive bulbar palsy
83
Mechanism of actionof lamotrigine? adverse effects?
Lamotrigine is an antiepileptic used second-line for a variety of generalised and partial seizures. Mechanism of action sodium channel blocker Adverse effects Stevens-Johnson syndrome
84
What is Cadasil?
Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) rare cause of multi-infarct dementia patients often present with migraine ## Footnote It usually presents with the onset of migraines in middle age, followed by recurrent TIAs and strokes, and resulting in neuro-cognitive decline, psychiatric problems and dementia. MRI often shows multiple widespread hyper-intense lesions in the white matter, basal ganglia, thalamus and pons.
84
What mutation is seen in CADASIL?
a mutation in the NOCTH3 gene.
85
Features of absence seizures?
bsences last a few seconds and are associated with a quick recovery seizures may be provoked by hyperventilation or stress the child is usually unaware of the seizure they may occur many times a day
86
What is seen on EEG in absence seizures?
EEG: bilateral, symmetrical 3Hz spike and wave pattern
87
Management and prognosis of absence seizures?
sodium valproate and ethosuximide are first-line treatment good prognosis - 90-95% become seizure free in adolescence
88
Mechanism of action of Pheytoin?
binds to sodium channels increasing their refractory period ## Footnote Phenytoin is also an inducer of the P450 system.
89
Acute sideeffects of Phenytoin?
Acute initially: dizziness, diplopia, nystagmus, slurred speech, ataxia later: confusion, seizures
90
Chronic adverse effects of phenytoin?
common: gingival hyperplasia (secondary to increased expression of platelet derived growth factor, PDGF), hirsutism, coarsening of facial features, drowsiness megaloblastic anaemia (secondary to altered folate metabolism) peripheral neuropathy enhanced vitamin D metabolism causing osteomalacia lymphadenopathy dyskinesia
91
Idiosyncratic side effects of phenytoin?
fever rashes, including severe reactions such as toxic epidermal necrolysis hepatitis Dupuytren's contracture* aplastic anaemia drug-induced lupus
92
Monitoring of phenytoin?
Phenytoin levels do not need to be monitored routinely but trough levels, immediately before dose should be checked if: adjustment of phenytoin dose suspected toxicity detection of non-adherence to the prescribed medication
93
Teratogenic effects of phenytoin?
associated with cleft palate and congenital heart disease
94
What is hyperacusis?
an increased sensitivity to sound.
95
What is hyperesthesia?
increased sensitivity to touch
96
What is hyperalgesia?
increased sensitivity to pain
97
Typical BPPV history?
vertigo triggered by change in head position (e.g. rolling over in bed or gazing upwards) may be associated with nausea each episode typically lasts 10-20 seconds
98
Classiucal features of Meniere's disease?
This can cause recurrent episodes of vertigo. However, it will be unrelated to head position, episodes typically last 2-3 hours and there may be other associated features like hearing loss and a sensation of aural fullness.
99
Classical features of viral labrythitis?
This can cause vertigo. However, it would typically cause vertigo after an infection that would result in one continuous episode that subsequently resolves rather than recurrent episodes Furthermore, viral labyrinthitis causes hearing loss (unlike vestibular neuritis),
100
Acute Management of migraines?
1st line - oral triptan plus NSAID/paracetamol if the above measures are not effective or not tolerated offer a non-oral preparation of metoclopramide or prochlorperazine and consider adding a non-oral NSAID or triptan caution should be exercised when prescribing metoclopramide to young patients as acute dystonic reactions may develop ## Footnote for young people aged 12-17 years consider a nasal triptan in preference to an oral triptan
101
Migraine prophylaxis?
propranolol topiramate: should be avoided in women of childbearing age as it may be teratogenic and it can reduce the effectiveness of hormonal contraceptives amitriptyline ## Footnote if these measures fail NICE recommends 'a course of up to 10 sessions of acupuncture over 5-8 weeks' NICE recommend: 'Advise people with migraine that riboflavin (400 mg once a day) may be effective in reducing migraine frequency and intensity for some people'
102
Treatment for menstrual migraine?
for women with predictable menstrual migraine treatment NICE recommend either frovatriptan (2.5 mg twice a day) or zolmitriptan (2.5 mg twice or three times a day) as a type of 'mini-prophylaxis'
103
Specialist treatments for migraines?
candesartan: recommended by the British Association for the Study of Headache guidelines monoclonal antibodies directed against the calcitonin gene-related peptide (CGRP) receptor: examples include erenumab
104
what is CJD?
Creutzfeldt-Jakob disease (CJD) is rapidly progressive neurological condition caused by prion proteins. These proteins induce the formation of amyloid folds resulting in tightly packed beta-pleated sheets resistant to proteases.
105
Features of CJD?
dementia (rapid onset) myoclonus
106
Investigations for CJD disease?
CSF is usually normal EEG: biphasic, high amplitude sharp waves (only in sporadic CJD) MRI: hyperintense signals in the basal ganglia and thalamus Hockey stick or ribbon sign is a feature of sporadic CJD
107
Sporadic CJD
accounts for 85% of cases 10-15% of cases are familial mean age of onset is 65 years
108
New varient CJD?
younger patients (average age of onset = 25 years) psychological symptoms such as anxiety, withdrawal and dysphonia are the most common presenting features the 'prion protein' is encoded on chromosome 20 - it's role is not yet understood methionine homozygosity at codon 129 of the prion protein is a risk factor for developing CJD - all patients who have so far died have had this median survival = 13 months
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what drugs may exacerbate Myasthenia gravis?
penicillamine quinidine, procainamide beta-blockers lithium phenytoin antibiotics: gentamicin, macrolides, quinolones, tetracyclines
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What may point towars a diagnosis of MND?
There are a number of clues which point towards a diagnosis of motor neuron disease: asymmetric limb weakness is the most common presentation of ALS the mixture of lower motor neuron and upper motor neuron signs wasting of the small hand muscles/tibialis anterior is common fasciculations the absence of sensory signs/symptoms vague sensory symptoms may occur early in the disease (e.g. limb pain) but 'never' sensory signs Other features doesn't affect external ocular muscles no cerebellar signs abdominal reflexes are usually preserved and sphincter dysfunction if present is a late feature
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Features of juvenile myoclonic epilepsy?
typical onset is in the teenage years, more common in girls features: infrequent generalized seizures, often in morning//following sleep deprivation daytime absences sudden, shock-like myoclonic seizure (these may develop before seizures) treatment: usually good response to sodium valproate
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Features of lennox gastaut syndrome?
may be an extension of infantile spasms onset 1-5 yrs features: atypical absences, falls, jerks 90% moderate-severe mental handicap EEG: slow spike treatment: ketogenic diet may help
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What is Benign rolandic epilepsy?
most common in childhood, more common in males features: paraesthesia (e.g. unilateral face), usually on waking up
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What is west's syndrome?
Infantile spasms (West's syndrome) brief spasms beginning in the first few months of life key features: flexion of head, trunk, limbs → extension of arms (Salaam attack); last 1-2 secs, repeat up to 50 times progressive mental handicap EEG: hypsarrhythmia usually secondary to serious neurological abnormality (e.g. tuberous sclerosis, encephalitis, birth asphyxia) or may be idiopathic possible treatments include vigabatrin and steroids has a poor prognosis
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What is Chorea?
Chorea describes involuntary, rapid, jerky movements which often move from one part of the body to another. Slower, sinuous movement of the limbs is termed athetosis. Chorea is caused by damage to the basal ganglia, especially the caudate nucleus.
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Causes of Chorea?
Huntington's disease, Wilson's disease, ataxic telangiectasia SLE, anti-phospholipid syndrome rheumatic fever: Sydenham's chorea drugs: oral contraceptive pill, L-dopa, antipsychotics neuroacanthocytosis pregnancy: chorea gravidarum thyrotoxicosis polycythaemia rubra vera carbon monoxide poisoning cerebrovascular disease
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What is the barthel index?
The Barthel Index measures the extent to which somebody can function independently and has mobility in their activities of daily living i.e. feeding, bathing, grooming, dressing, bowel control, bladder control, toileting, chair transfer, ambulation and stair climbing.