Neurology Flashcards

1
Q

Antibody associated with Miller Fisher syndrome

A

GQ1B antibodies - present in 90-95% of MFS cases

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2
Q

Antibodies associated with Acute Motor Axonal neuropathy

A

GD1a, GM1

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3
Q

Antibodies associated with sensory GBS

A

GD1b

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4
Q

Poor prognostic factors for GBS

A

Rapid onset prior to presentation (<7 dayys)
High disability nadir
Mechanical ventilation
Severely reduced CMAPs
Older than 40 yrs
Preceding diarrhoea illness - Campylobacter jejui
Preceding infection with CMV
Inexcitable nerves

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5
Q

Definition of epilepsy

A
  1. At least two unprovoked (or reflex) seizures occurring > 24 hours apart
  2. One unprovoked seizure and probability of further seizures similar to general recurrence risk after two unprovoked seizures, occurring over next 10 yrs
  3. Diagnosis of epilepsy syndrome
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6
Q

Classification of seizures

A

Focal onset
- Aware vs impaired awareness
- Motor or non motor onset
- Focal to bilateral tonic-clonic

Generalised onset
- Motor - tonic clonic vs other motor
- Non-motor - absence

Unknown onset

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7
Q

Focal seizure semiology

A

Temporal - deja vu, olfactory aura, epigastric rising feeling, oral automatisms
Occipital - simple visual hallucinationrs
Primary auditory - buzzing/ringing
Primary motor - focal clonic activity
Frontal - complex motor behaviour

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8
Q

Management of focal seizures

A

1st line - Carbamazepine
Other agents - lamotrigine, topiramate, levetiracetam, gabapentin

Surgical procedures - temporal lobectomy, lesionectomy, cortisectomy, implanted devices

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9
Q

Childhood absence epilepsy

A

Onset between age 4-10
Dominant seizure type absence seizures (rare GTCS)

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10
Q

Juvenile absence epilepsy

A

Onset over age 10
Commonly absence, but more likely GTCS and may have myoclonus

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11
Q

Juvenile myoclonic epilepsy

A

Onset over age of 10
Myoclonus common - occurring early morning or shortly after walking
GTCS common and absence can occur

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12
Q

Lennox Gastaut syndrome

A

Occurring in early childhood
Multiple seizures types
Associated with developmental disability

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13
Q

Management of generalised epilepsy

A

Sodium valproate
Levetiracetam
Lamotrigine
Topiramate

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14
Q

Management of absence seizures

A

Ethosuximide

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15
Q

Structural lesions for epilepsy

A

Hippocampal sclerosis
- defined by increased T2 signal and reduced size
Benign tumours
- dysembryoplastic neuro-ectodermal tumour
- ganglioglioma
- cortical dysplasia
Vascular malformations
- cavernoma
- arterio-venous malformation
Malignant lesions
- metastatic
- primary

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16
Q

AEDs in pregnancy

A

Lamotrigine
- 2-3 fold increase in metabolism during pregnancy
- metabolism enhanced by oestrogen
Levetiracetam
- increased renal clearance in 2nd-3rd TM

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17
Q

HLA association between SJS and carbamazepine

A

HLA B*1502
Associated greatest in Asian ancestry

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18
Q

Treatment of status epilepticus

A

1st line - IV/IM benzodiazepine (midaz, loraz)
2nd line - Levetiracetam, phenytoin, sodium valproate

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19
Q

Indication of cannabidiol in management of epilepsy

A

Dravet syndrome
Lennox Gastaut syndrome

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20
Q

Dravet syndrome

A

Severe epilepsy syndrome due to Na+ gene mutation (SCN1A) treatment refractory seizures of multiple types

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21
Q

Risk factors for SUDEP

A

Male gender
Young age
Non-compliance
Poorly controlled epilepsy
Prone sleeping
Sleeping alone

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22
Q

Risk and protective factors for Parkinson’s disorder

A

Risk factors:
- Age
- Pesticide/solvent exposure
- Farmers
- High levels of education
- History of TBI
- Low sunlight/vitamin D
- Melanoma
- Genetics

Protective:
- Smoking
- Artistic occupation

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23
Q

Genetic markers for PD

A

PARK 1-15

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24
Q

Pathogenesis of PD

A

a-synuclein key protein in pathogenesis of PD
- prone to mutate and form insoluble species which aggregate in neurons through genetic or environmental factors
- spread in prion-like fashion through CNS

Lewy body
- pathological hallmark of PD
- composed of alpha synuclein

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25
Clinical features of PD
In order of progression: Change in bowel habits/constipation RBD EDS Hyposmia Depression Motor symptoms Urinary symptoms, postural hypotension Hallucinations, psychosis, dementia
26
Non-motor features of PD
REM sleep disorder Hyposmia Depression Urinary symptoms Psychosis Reduced libido ED
27
Motor features of PD
Presence of bradykinesia Rigidity Resting tremor Postural instability Unilateral onset Progressive disorder Persistent asymmetry Responsive to levodopa
28
MRI sign of MSA
Hot cross bun sign T2 hyperintense cruciform appearance of pons Increased signal in transverse pontocerebellar fibers MSA-C (cerebellar types)
29
MRI sign of PSP
Hummingbird sign Midbrain strophy Preserved pontine volume Mickey mouse appearance Reduction in AP diameter of midbrain
30
MRI sign of Wilson's disease
Giant panda sign Relative hyperintensity of basal ganglia and mid brain
31
Treatment of early PD
Exercise Maintaining and improving mobility, flexibility, range of motion, speed of movement Easing secondary symptoms i.e. depression and constipation Commence treatment when functionally disabled - L-dopa, dopamine agonist, MAOI-B
32
Considerations with levodopa
Higher risk of dyskinesias over other PD treatments Honeymoon period - beneficial effect in early phase of treatment
33
Consideration of dopamine agonist use
Initial therapy in patients < 60 yrs In combination with L-dopa, motor fluctuations and dyskinesias reduced
34
Side effects of dopamine agonists
Sleepiness Peripheral oedema Neuropsychiatric SEs particularly in pts > 70 yrs Impulse control disorders
35
Dopamine agonist examples
Pramipexole Apomorphine
36
MAO B inhibitors indications and considerations
Selegiline Trial as initial therapy for mild disease in pts with bradykinesia or postural instability May improve end of dose akinesias May worsen dyskinesias
37
Indications and considerations of NMDA antagonist
Amantadine Short term treatment of mild symptoms Levodopa induced dyskinesia Akinetic crisis May cause adverse CNS effect
38
Indications for functional neurosurgery
Motor complications not managed by medical treatment
39
Types of functional neurosurgeryy
Thalamic stimulation (DBS) - tremor Pallidal stimulation - dyskinesias Subthalamic stimulation - motor fluctuations
40
Advanced therapies for PD
Duodopa L-dopa gel SC apomorphine
41
Pathophysiology of cognition impairment in PD
Lewy bodies spread in involve cortex
42
Pathophysiology of PD
- Progressive dopaminergic neuron degeneration in the substantia nigra (part of the basal ganglia) and the locus coeruleus → dopamine deficiency at the respective receptors of the striatum with interrupted transmission to the thalamus and motor cortex → motor symptoms of PD - Indirect pathway of the basal ganglia is affected - Serotonin and noradrenaline depletion (in the raphe nuclei): likely cause of depressive symptoms - Acetylcholine surplus (in the nucleus basalis of Meynert): likely cause of dyskinesia
43
Pathophysiology of Lewy Body dementia
If motor symptoms precede by < 1 year + dementia
44
Clinical features of LBD
Visual hallucinations Fluctuations in GCS PD motor symptoms Neuroleptic sensitivity (cog and motor) Paranoia
45
Friederich's ataxia features
Trinucleotide repeat expansion (of the nucleotide triplet GAA) in the FXN gene on chromosome 9 Progressive ataxia Spastic paralysis Nystagmus Dysarthria HOCM DM Scoliosis
46
Fragile X associated tremor ataxia syndrome features
X-linked dominant disease caused by a CGG trinucleotide repeat expansion in the FMR1 gene (fragile X mental retardation 1 gene) Late onset ataxia Postural tremor Executive deficits Parkinsonism Neuropathy Increased T2 signal in cerebellar peduncles
47
Huntington disease features
Autosomal dominant Increased number of CAG repeats (trinucleotide or triplet repeat expansion) in the huntingtin gene on chromosome 4 Mean age onset 45 yrs, median survival 18 yrs
48
CAG repeats in Huntington disease and interpretation
Normal: < 26 Intermediate: 27-35 --> no development of symptoms, but children at risk Reduced penetrance: 36-39 --> may or may not develop symptoms at any age Full penetrance: > 40 --> have disease
49
Imaging for Huntington disease
Neuronal loss and atrophy of caudate putamen
50
Clinical features of Huntington disease
Motor - chorea, motor impersistence, dysarthria, ataxia, trouble walking, dystonia Psych - depression, anxiety, apathy, paranoia Dementia - Impulsive, personality change, social withdrawal, cognitive slowing, weight loss
51
Findings of demyelinating lesions in NCS
Slowed conduction velocity Conduction block Temporal dispersion Lower amplitudes due to distal dispersion or conduction block Delayed or absent F-waves
52
Findings of axonal lesions in NCS
Low amplitudes
53
Recovery of neurapraxia/demyelination
Remyelination of local Schwann cells Weeks to months
54
Recovery of axonal loss/axonotmesis/neurotmesis
Axonal regrowth -1mm/day, 1 inch/month Distal branch sprouting
55
Carpal tunnel syndrome clinical features
Sensory disturbances (pain, tingling, and numbness) and motor symptoms (weakened thenar muscles leading to weakened pinch and grip of the thumb) in the area innervated by the median nerve distal to the carpal tunnel
56
Radial neuropathy clinical features
Sudden painless wrist and finger drop Compression at spiral grooves, triceps spared Sensory loss of dorsum of hand, especially thumb and index
57
EMG findings in acute denervation
Prominent fibrillation/positive sharp waves Reduced recruitment in proportion to number of motor units lost
58
EMG findings of chronic denervation
No fibrillation potentials Increased duration Increased amplitude Reduced recruiment
59
EMG findings of myopathy
Minimal fibrillations, may be present in some myopathies Decreased duration Decreased amplitude Small amplitude, recruited early
60
Clinical manifestations of anterior horn cell disease
Progressive, asymmetric motor disorder with mixed proximal/distal, UMN and LMN signs One of four body segments (cranial/bulbar, cervical, thoracic, and lumbosacral) - Sparing eye movements, bowel and ladder - Tongue fasciculations - Painless - Region spread within and to adjacent regions - "Split hand syndrome"
61
MND epidemiology
Sporadic - 5% dominantly inherited Mean age of onset 55 yrs Median survival from diagnosis 3-5 yrs
62
Variants of MND
Amyotrophic lateral sclerosis - mixed UMN and LMN Spinal muscular atrophy - predominant LMN Primary lateral sclerosis - predominant UMN, better prognosis Progressive bulbar palsy
63
MND EMG findings
Findings of acute and chronic denervation and reinnervation - Fasciculations in muscles with chronic denervation - Fibrillations and positive sharp waves with acute denervation
64
MND NCS findings
No conduction block Normal or near normal motor conduction velocities Normal sensory studies
65
Gold coast criteria for ALS
1. Progressive motor impairment documented by history of repeated clinical assessment, preceded by normal motor function AND 1. Presence of UMN and LMN dysfunction in at least 1 body region with - UMN and LMN dysfunction noted in same body region OR LMN in at least 2 body regions AND 1. Investigations excluding other disease processes
66
Clinical features of multifocal motor neuropathy with conduction block
Progressive, asymmetrical, predominantly distal, pure motor, LMN pattern with some atrophy Upper limbs > lower Cramps and fasciculations common CN involvement rare Absent sensory symptoms
67
Clues to diagnosis of MMCB
Age Weakness > atrophy Peripheral nerve pattern of weakness Absence of CN or UMN signs Depressed or absent tendon reflexes Unusual sites of focal demyelination
68
Investigation findings of multifocal motor neuropathy w/ conduction block
NCS - partial conduction block in one or more nerves, sensory nerves normal IgM anti-GM1 antibodies
69
Management of MMCB
IVIg IV cyclophosphamide Plasma exchange Rituximab Prednisone can worsen it
70
MMN clinical features
Stepwise, multifocal, asymmetric, can be distal or proximal Eventually becomes symmetrical
71
MMN causes
Diabetes Infectious - leprosy, HIV Arteritis - CTD, vasculitis Trauma Hereditary liability to pressure palsies Sarcoidosis Malignancy
72
Causes of peripheral neuropathy
Metabolic - diabetes, uraemia, porphyria, hypothyroidism, acromegaly, EtOH, B1/B6/B12/niacin deficiency Infections - HIV, lyme, leprosy Toxic - drugs, poisons Inherited - CMT, Frederich's ataxia CTD - RA, PAN, SLE, Sjogren's, Wegener's, Churg-Strass Paraproteinaemias - MM, MGUS, POEMS, amyloid Immune mediated - GBS, CIDP, MMCB, POEMS, Amyloid
73
Charcot Marie Tooth disease subtypes
CMT I - demyelinating (AD/X linked) - Due to duplication of PMP 22 gene: CMT1A Hereditary neuropathy with pressure palsies - PMP 22 deletion/point mutation CMT IX - X linked dominant CMT II- axonal
74
CMT genetics
PMP22 GJB1 - CMT1X MFN2 - CMT 2A MPZ - CMT1B
75
Types of diabetic neuropathies
Symmetric polyneuropathies - sensory - sensorimotor --> distal, length dependent --> sensory > motor. axonal > demyelinating - autonomic Focal and multifocal - CN palsies - Radiculopathies - Mononeuritis - Asymmetric proximal neuropathy (amyotrophy) - Treatment induced
76
Investigations of peripheral neuropathy
NCS Metabolic screens Autoimmune and paraprotein screens ESR, CRP Toxic screen LP Consider cancer screen, HIV, sural nerve biopsy
77
What feature on NCS most sensitive in detection of early diabetic polyneuropathy?
F wave latency
78
GBS features
Acute, demyelinating, autoimmune neuropathy Asymmetric, patchy and global Weakness, sensory features and autonomic disturbance developing over days
79
Triggers for GBS
URTI, GIT infection, immunisation, surgery, trauma Specific agents: campylobacter jejuni, EBV, CMV, mycoplasma, viral hepatitis, HIV, seroconversion
80
Clinical variants of GBS
Miller Fisher syndrome - External ophthalmoplegia, ataxia, areflexia - GQ1B Polyneuritis cranialis Pure sensory variant Acute autonomic neuropahty Acute axonal variant - Acute motor axonal neuropathy (AMAN) (AMSAN) - Pharyngeal-cervical-brachial variant
81
Investigations of GBS
CSF - Elevated protein NCS - conduction slowing, block, long latencies and delayed F waves EMG - may shown denervation changes 2-4 weeks
82
Treatment of GBS
IVIg Plasma exchange
83
Clinical criteria for typical CIDP
Chronically progressive, stepwise or recurrent Symmetric proximal and distal weakness Less prominent sensory dysfunction Absent or reduced reflexes Minimal autonomic involvement
84
Clinical criteria for atypical CIDP
Predominantly distal (DADS) Asymmetric (MADSAM) Focal Pure motor Pure sensory
85
Clinical features of CIDP
Progress or relapse/remit over > 8 weeks Symmetric weakness of both proximal and distal muscles ↓ Deep tendon reflexes in both upper and lower extremities Sensory involvement (e.g., paresthesias) Autonomic dysfunction and cranial nerve involvement are rare. CIDP variants can manifest with asymmetric symptoms and/or purely sensory or motor symptoms.
86
Investigation findings of CIDP
LP - Increased protein, low cell count NCS - slow CV, conduction block or temporal dispersion, prolonged DML, absent/prolonged F-waves
87
Treatment of CIDP
Prednisone Plasma exchange IVIg Azathioprine
88
Features of distal acquired demyelinating symmetric neuropathy (DADS-M)
Elderly males Predominant distal sensory loss Mild distal weakness - foot drop, ataxia Associated unsteadiness/falls/tremor
89
Investigation findings of DADS-M
Prolongation of distal latencies on NCS IgM paraproteinaemia in 2/3 Anti MAG
90
Features of myasthenia gravis
Fatiguable weakness 90% of cases involve extraocular muscles 80% involve facial and bublar muscles 50% involve purely ocular disease 50% progress to generalised myasthenia
91
Myasthenia and thymoma
Almost all thymoma associated with MG Thymic lymphoid hyperplasia in 70% Thyrotoxicosis in 5%
92
Diagnosis of MG
Repetitive stimulation - decremental response at low frequency ACh receptor antibodies - 85% of pts with generalised MG, 60% with ocular MG Anti-MuSK - high frequency in bulbar involvement and respiratory crises Tensilon test - Positive in 80%
93
Features of LEMS
Antibody to presynaptic voltage gated calcium channel, reducing number of vesicles released Proximal muscle weakness; muscle strength improves with repetitive or ongoing use Reduced or absent reflexes Autonomic symptoms
94
Causes of LEMS
Paraneoplastic - SCLC AI disorder
95
Diagnosis of LEMS
EMG: Repetitive nerve stimulation results in incremental responses. NCS: Small initial CMAP, increases after voluntary contraction or high frequency stimulation Confirmatory test: anti-VGCC antibodies in serum Other: CT chest, abdomen, and pelvis to screen for underlying malignancy
96
Treatment of LEMS
Plasma exchange Prednisone Azathioprine Guanidine Diaminopyridine
97
Features of statin myopathy
Symptom onset at any time - 25% after > 12 month usage Mild myalgias --> severe rhabdomyolosis Self-limiting, lasting ~2-3 months Elevated CK levels Myalgias common symptom
98
General principles of stroke anatomy
ACA - leg weakness MCA - hemiplegia, hemiparesis with cortical signs. if dominant side, can have speech deficits. PCA - visual field deficits Penetrating vessels in subcortical - hemiplegia or hemiparesis without cortical signs
99
Causes of ICH
Idiopathic Hypertensive Amyloid angiopathy --> microhaemorrhage, SAH, cortical calcification Vascular abnormality Secondary to ischaemic stroke Trauma Underlying bleeding disorder Anticoagulation related Drug related
100
Management of cerebral haemorrhage
Surgery for significant compression Aim SBP < 140mmHg Reversing agents for anticoagulation Fibrinolytics beneficial in first 24 hours from onset
101
Risk factor screening for stroke
HTN Hypercholesterolaemia Diabetes Precoagulant states/IE AF or other source of cardio-embolic source Collagen disorders, vascular dissection, rare genetic causes
102
Risk of stroke in TIA
In 48 hours - 6% In 1 week - 10% In 6 months - 17%
103
Stroke prevention strategies
Early carotid surgery for symptomatic stenosis after TIA and mild stroke Antiplatelet agents Anticoagulation for non valvular AF Antihypertensives aiming BP < 130/85 High dose cholesterol lowering agents Lifestyle advice
104
DAPT duration
Usual DAPT for 3 weeks and then stepdown to SAPT If high risk intracranial atherosclerosis, consider longer duration of 90 days
105
Time windows for acute stroke therapy
IV thrombolysis up to 9 hours if evidence of salvageable tissue Endovascular therapy up to 24 hours
106
DOACs for embolic stroke
ARISTOPHANES study Apixaban - less stroke/embolic events, less major bleeds Rivaroxiban - higher bleeding risk
107
Most likely location for thrombus in AF
Left atrial appendage
108
Device for AF if DOAC not appropriate
Left atrial appendage oclusion
109
Evidence re: LAAO compared to DOACs
Prague 17 study Left atrial appendage occlusion non-inferior to DOAC at preventing embolic events/bleeding
110
Risk stratification of PFO and stroke
Characteristics - Large shunt - septal aneurysm Clinical - age - stroke features - ROPE score - hypercoagulopathy - Concomitant VTE - competing risks
111
COVID-19 and stroke
Associated with hypercoagulable state +/- direct infection/inflammation of blood vessels Mostly causing large vessel occlusion More likely to develop: - AKI - Hepatic failure - Respiratory failure
112
Stroke mimics
Focal seizures Migraines Tumour SDH Hypotension/syncope Peripheral vestibular conditions Panic attacks Conversion disorders/FND
113
Tenectoplase vs alteplase for acute stroke therapy
Alteplase = tenectoplaste - equally more effective up to 4.5 hours
114
Hypertension in stroke population
Up to 70%
115
Definition of MS
Chronic inflammatory autoimmune disease of CNS characterised by inflammation, demyelination and axonal loss
116
Braak staging
Lower brainstem and olfactory system (dorsal motor nucleus of vagus nerve, anterior olfactory nucleus) > medulla oblongata > pontine tegmentum > basal mid- and forebrain, hypothalamus, thalamus > mesocortex, allocortex > neocortex
117
Risk factors for MS
Caucasian Female If affected sibling High latitude of residence Low vitamin D levels Smoking Obese Inadequate sleep in adolescence
118
Genetic risks of MS
HLA-DRB1+15:01 confers greatest risk
119
EBV and MS
Increased risk of MS linked to antibody response to EBV nuclear antigen
120
Role of myelin and oligodendrocytes
Oligodendrocytes responsible for myelinating axons in CNS Myelin increases speed of electrical conduction Oligodendrocyte provides trophic support to neurons
121
Immunopathogenesis of MS
1. Peripheral activated autoreactive T cells (especially Th17) migrate across blood brain barrier 2. Reactivation by local antigen presenting cells 3. Clonal expansion 4. Secretion of proinflammatory cytokines 5. Stimulation of microglia and astrocytes 6. Destruction of myelin, oligodendrocyte loss, and axonal loss
122
Acute vs chronic demyelinated plaque
Acute plaque - indistinct margin - inflammatory cells centred around vessels in 'perivascular cuff' - oedema and demyelination throughout plaque - oligodendrocyte and axonal loss varialbe Chronic plaque - more distinct borders - hypocellular core with thickened vessels and enlarged perivascular spaces - loss of myelin and glial scarring prominent
123
Clinical phenotypes of MS
Relapsing remitting MS (85-90%) Primary progressive (10%) Secondary progressive MS Primary relapsing MS
124
Definition of relapse
Any new or worsening neuro symptoms that last longer than 24 hours, or shorter than 24 hours but recurs repeatedly over days
125
Definition of pseudorelapse
Previous neuro symptoms may temporarily worsen if body temperature is elevated --> reflects conduction block in previously demyelinated axons
126
Typical MRI lesions in MS
Corpus callosal Periventricular "Dawson fingers" Infratentorial
127
Role of oligoclonal bands
Represents immunoglobulins to specific antigens within CNS Found in CNS
128
Role of VEP
Measures time taken for visual stimulus to be recorded over occiput Normal VEP virtually excludes a lesion of optic nerve or along visual pathways in anterior brain
129
Diagnostic criteria for RRMS
>/2 clinical attacks + MRI findings or good historical evidence 1 clinical attack with typical MRI + follow up MRI with new lesion and/or OCB present in CSF
130
Diagnostic criteria for PPMS
1 year of disability progression independent of clinical relapse + two of following criteria - >1 T2 hyperintensive lesion characteristic of MS in one or more following brain regions (periventricular, cortical or juxtacortical or infratentorial) - >2 T2 hyperintense lesions in spinal cord - Presence of CSF specific oligoclonal bands
131
Definition of neuromyelitis optica spectrum disorder (NMOSD)
Immune mediated disease causing demyelination and axonal damage or optic nerves and spinal cord
132
Pathology of NMOSD
Necrosis and cavitation involving both gray and white matter Majority of patients have aquaporin-4 antibodies - crosses BBB and binds to water channels on astrocytes - activates complement system/MAC causing complement dependent cytotoxicity - stimulates Ab-dep cellular toxicity - death to astrocytes followed by oligodendrocytes and neurons - oligodendrocytes loss leads to demyelination
133
Neuroimaging in NMOSD
Longitudinally extensive spinal cord lesion (LETM) Long optic nerve lesion, often involving posterior aspects of nerve or optic chiasm Lesions involving dorsal medulla Lesions involving hypothalamus/thalamus
134
Clinical characteristics of NMOSD
1. Optic neuritis 2. Acute myelitis 3. Area postrema syndrome (intractable hiccups, N+V) 4. Acute brainstem syndrome 5. Symptomatic cerebral syndrome with NMOSD-typical brain lesions
135
Treatment of NMOSD
IV methylpred + oral corticosteroids +/- PLEX Steroid sparing agents (MMF, azathioprine) B cell depleting therapy
136
Pathophysiology of MOGAD
Myelin oligodendrocyte glycoprotein exclusively expressed on oligodendrocytes and myelin. inCNS Anti-MOG Ab --> demyelination
137
Presentation of MOGAD
Bilateral (consecutive) optic neuritis Typically very severe Steroid responsive with good recovery of vision
138
Poor prognostic factors in MS
Frequent relapses within first 2 years of diagnosis Short interval between first 2 relapses Rapid early disability progression High lesion load (especially spinal cord or infratentorial) Cerebral atrophy Male gender Later age of onset
139
MOA of natalizumab
alpha 4 integrin monoclonal Ab (found on monocytes and lymphocytes)
140
Natalizumab SEs
Increased risk of herpes virus reactivation Risk of progressive multifocal leukoencephalopathy, caused by JC virus
141
Higher risk of PML if
JCV serology positive and: - Any prior immunosuppression - >2 yrs on natalizumab - JCV index (level of positivity)
142
MOA of alemtuzumab
Anti-CD52 (found on differentiated lymphocytes and monocytes) --> eliminates pathogenic T cells
143
Alemtuzumab SEs
Infusion reactions common Increased infection risk Risk of secondary autoimmunity (thyroid disease, ITP)
144
MOA of ocrelizumab
Anti-CD20 fully humanised monoclonal Ab
145
Ocrelizumab SEs
Infusion reactions common Increased infection risk Risk of PML Increased risk of malignancies (though not significant)
146
MOA of ofatumumab
Fully humanised monoclonal antibody against CD20+ B cells
147
MOA of cladribine
Selective immune reconstitution therapy Deoxyadenosine analogue prodrug selectively targets lymphocytes due to preferential intracellular activation
148
Cladribine SEs
Lymphopenia Increased risk of infections (whilst lymphopenic)
149
MOA of fingolimod
Binds to S-1-P receptors on lymphocytes and blocking their egress from lymph nodes
150
Fingolimod SEs
First dose bradycardia - requires cardiac monitoring when first given LFT derangement Lymphopenia Increased infection risk especially herpes virus Increased risk of non-melanomatous skin cancers PML risk
151
Ozanimod MOA
Sphingosine-1-phosphate inhibitor Slightly different receptor specificity and lower risk of cardiac complications
152
Dimethyl fumarate MOA
Modulates antioxidative pathways via activation of Nrf2
153
Dimethyl fumarate SEs
Flushing GIT upset Lymphopenia Rare LFT deranagements Risk of PML
154
MOA of teriflunomide
Inhibits dihydroorotate dehydrogenase and interferes with pyrimidine synthesis
155
SEs of teriflunomide
Hepatotoxicity Hair thinning HTN GI upset Teratogenic
156
MOA of glatiramer acetate
Synthetic polypeptide antigenically similar to myelin basic protein
157
MOA of interferon beta 1a and 1b
Diverts immune system away from proinflammatory Th1 and Th17 pathways to more anti-inflammatory Th2 pathway Also effects T-reg, NK cells, B-cells and lymphocyte migration into BBB
158
Washout periods for MS drugs prior to conception
None - Glatiramer acetate - Interferon beta - Dimethyl fumarate - Natalizumab 2 months - Fingolimod 4 months - Alemtuzumab 6 months - Cladribine - Ocrelizumab/Ofatumumab Accelerated elimination - Teriflunomide
159
Prognosis of MS
Untreated MS, ~50% of pts develop SPMS after 10-20 yrs of RRMS diagnosis
160
Cortical signs of frontal lobe
Personality Primitive reflexes Dysphasia expressive Anosmia Optic nerve compression Gait apraxia
161
Cortical signs of parietal lobe
Gerstmann syndrome - acalculia, agraphia, L-R disorientation, fingeragnosia Sensory, visual and spatial inattention Construction and dressing apraxia Lower quandrantanopia
162
Signs of Gerstmann syndrome
Dominant, angular gyrus Acalculia Agraphia L-R disorientation Fingeragnosia
163
Cortical signs of temproal lobe
Receptive dysphasia (dominant) Memory loss Upper quandrantanopia
164
Cortical signs of occipital lobe
Homonymous hemianopia Anton's syndrome Alexia without agraphia
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Signs of Anton's syndrome
Cortical blindness with confabulation
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Types of aphasia
Non-fluent, Expressive, Broca's, transcortical motor - Able to comprehend, paucity of word - Usually frustrated - Dominant frontal lobe Fluent, receptive, Wernicke's, transcortical sensory - Unable to comprehend, fluent but incomprehensible speech - Not frustrated - Dominant temporal lobe Conduction aphasia - Mix between the two - Able to comprehend elements of fluent aphasia and poor repetition
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Thalamus sign and functions
Terminal for all sensory nerves Arterial supply from PCA Anterior nuclei - language and memory function Lateral nuclei - motor and sensory function Medial nuclei - maintaining arousal and memory Posterior nuclei - visual function
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Peripheral cerebellum signs
Ipsilateral limb ataxia Past pointing Dysmetria Intention tremor Dysdiadochokinesia Nystagmus
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Vermis cerebellum signs
Truncal ataxia Nystagmus (flocculonodular lobe)
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4 rules of brainstem
1. 4 cranial nerves in medulla, 4 in pons, 4 above pons 2. 4 structures in midline beginning with M 3. 4 structures to side beginning with S 4. 4 motor nuclei in midline
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4 medial structures
Motor pathway Medial lemniscus Medial longitudinal fasciculus Motor nucleus
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4 side structures
Spinocerebellar pathways Spinothalamic pathways Sensory nucleus of 5th CN Sympathetic tract
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CN location in brainstem
Midbrain - III, IV Pons - V, VI, VII, VIII Medulla - IX, X, XI, XII
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Brown-Sequard syndrome
Ipsilateral UMN weakness below level of lesion Ipsilateral impairment of vibration and position sense below level of lesion Contralateral pain and temperature sensation from one to two segments below lesion Ipsilateral LMN weakness and complete sensory loss at level of lesion
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Central cord syndrome
Loss of pain and temperature in one or more adjacent dermatomes bilaterally at level of lesion Sensory classically seen in "cape" or "vest" distribution across neck and shoulders or trunk Further expansion affects lateral corticospinal tracts causing UMN weakness and temperature and sensation loss below lesion
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Anterior cord syndrome
Dorsal columns preserved Proprioception and vibration preserved Usually ischaemic with occlusion on anterior spinal artery
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Posterior cord syndrome
Just loss of dorsal column Rarely ischaemic given bilateral blood supply Demyelination, nutritional, genetic