Week 15 - Neurology

• 1 → Olfactory → smell
• 2 → Optic → Vision
• 3 → Occulomotor → 4/6, levaetor pelpebrae sup, pupil constrictors
• 4 → Trochlear → motor to superior oblique, long course
• 5 → Trigeminal → sensation face [3 segments] muscles of mastication [messeter, pterygoid & temporalis]
• 6 → Abducens → lateral rectus [abduct eye]
• 7 → Facial → sensory ant 2/3 tongue [taste], motor = facial muscles
• 8 → Vestibulocochlear → sensory, balance & hearing
• 9 → Glossopharyngeal → sensory post 1/3 tongue, motor soft palate, salivary glands
• 10 → Vagus → longest, chemoceptors in carotid bodies, HR, SV etc
• 11 → Spinal Accessory → motor to sternocleidomastoid & trapezius
• 12 → Hypoglossal → motor to tongue [deviate to affected side]

• Pancoast tumour invasion of cervical/thoracic sympathetic chain
• Affects CN 3 & 6
• signs
• Ptosis
• Miosis
• Anhidrosis
• Enopthalmus

• Eyelid droop [Ptosis]
• Eye in down & out position

Longest intracranial course → susceptible to tumour/ ^^ICP

• Head tilt away from lesion
• Hypertropia [one eye higher than other]
• when looking down towards nose, other eye moves upwards

Brainstem = Midbrain, pons & medulla

• Origin of all cranial nerves
• all spinal tracts pass thru here

• Basal Ganglia
• Caudate nucleus
• PutamenGlobus pallidus [interna & Externa]
• Subthalamic Nucleus
• Substansia Nigra
• Venterolateral nucleus of thalamus

• Initiate voluntary movement
• Maintain posture/ movement
• Eye movement
• Executive functions → working memory

• Lewy body → intracytoplasmic inclusion body containing misfolded protein
• gradually ascend thru stem
• loss of dopaminergic neurones within substansia nigra [CF >50% loss]

• Staging
• 1 → Lewy bodies in lower brain stem
• 3-4 → midbrain/ substansia nigra ~symptomatic
• 6 → throughout basal ganglia, severely demented

• CF
• Bradykinesia → slow to initiate voluntary movement, reduction in sped of following movements
• Muscular rigidity
• postural instability
• asymetrical

Non motor → dementia, poor sleep [restless legs] ^^ANS [constipation, ED, urinary urgency]

• CT/ MRI = normal
• Abn in vascualr/ parkinson plus disorders

Functional imaging → DAT SPEC → dopaminergic sys

• Benign tremor disorder
• dementia w lewy bodies
• Vascular Parkinsons [Stepwise progression, leg symptoms]
• Parkinson plus disorders
• Drug induced parkinsonism → dopamine antagonists

• 1. Replace DA/ DA agonists
• Levodopa
• MoA → DA precursor, crosses BBB, converted to DA in brain
• A/E → abn voluntary movement, confusion & hallucinations
• PK/PD → give with decarboxylase inhibitor or will convert in tissues → lethal

• Pramipexole
• MoA → DA-r agonist [D2]
• A/E → nausea, headache & vom

• 2. Prevent DA synapse degredation
• Entacapone/ Selegiline
• MoA → MAO-B inhibitors, prevent DA degredation, ^^acting DA

• 3. Reduce Action of ACh
• Benzotropine
• MoA → anticholinergic, reduces tremor & rigidity

• Myasthenia Gravis
• Acquired autoimmune disorder

CF → muscle weakness & ^^fatigueability on exertion

Complications → respiratory failure, dysphagia, long term steroid use

• Pathology
• B cell mediated
• Ab against ACh-R
• reduced receptors = reduced Na influx
• smaller end plate potential → no muscle movement

• Neostigmine/ Endrophonium
• MoA → acetyl cholinesterase inhibitors, ^ACh at junction, muscle movement
• A/E → Cholinergic crisis [sweating, salivation, miosis]

• Prednisalone
• MoA → immunosuppression, decrease circulating Ab
• A/E → cushings

• MS
• Chronic disease of brain & SC
• CF → changes in sensation, visual problems, weakness, poor coordination & speech, impaired mobility → disability

• Peak onset ~30yo
• Unknown cause

• CD4 T cells activate B cells → anti-myelin Ab
• Macrophages & Cytotoxic T → demyelination
• Failure of conducton & loss of function
• Eventual remyelination but never same function

CNS only

• Relapsing remitting
• Commonest
• decent recovery from initial attacks, variable freq
• 70% → secondary progressive MS

• Secondary Progressive MS
• gets steadily worse, after initial relapsing remitting course of disease

• Primary Progressive
• Worst prognosis
• >m:f
• Progressive spinal damage

• Progressive relapsing
• gets steadily worse with occaisional really bad patches

Could be anything, most neuro problems

• Relapsing remitting → clinically isolated syndromes
• e.g.
• optic neuritis [PAIN]
• Brainstem syndrome → opthalmoplegia, dyarthria, ataxic
• Spinal cord → transverse myelitis

2 clinical attacks, >1m apart & O/E evidence of 2 separate lesions

• MR brain & Spine → T2 & FLAIR weighted
• lesions → paraventricular, corpus callosum, BS/Cerebellum

• CSF → Lumbar puncture
• Oligoclonal bands → IgG heavy chains

• Prednisalone for first timers
• Refer to MS specialist nurses
• PT/ OT
• Later → Natalizumab → anti-TNF alpha

• Pronator Drift [indicates spasticity]
• ^^tone
• Brisk Reflexes
• Extensor Plantar Response

UMN lesion → lower half of face = paralysed

• Flaccid Paralysis
• Muscle loss → weakness
• Fasciculations
• Hypotonic
• Areflexic

LMN → complete facial paralysis

When BF stops, not instant tissue death

• Tissue death via;
• apoptosis
• inflammation
• oxidative stress
• excitotoxicity → breakdown of Na/K pumps [K out, Na in], water in cell swells, stimulate Glu release, ^^Ca, Protease activeation → cell degredation

• Geography
• Infarct core = irreversible dam
• Ischaemic Penumbra = potentially salvageable sorrounding tissue
• Benign oligaemia

• ^age
• HBP
• Heart Disease [AF]
• Smoking
• Diabetes
• Hypercholestrolaemia
• Previous stroke/ TIA
• FH

• Hypertension
• Cerebral Amyloid Angiopathy
• Anti-Coagulants
• Antiplatelet medication
• Dementia
• ^age
• Male
• Illegal drugs → cocaine
• Hypocholestrolaemia
• Vascular lesions → aneurisms

• TACS → Total Anterior Circulation Syndrome
• All 3 of; Contra-lateral hemiparesis, contra-lateral hemianopia, higher dysfunction [dysphasia, visuospatial]
• MCA/ICA occlusion

• PACS → Partial Anterior Circulation Syndrome
• 2 of above or higher function dysfunction alone
• MCA branch

• LACS → Lacunar Stroke
• small lacunae of blood [stroke]
• Pure motor or pure sensory or sensorimotor [Ataxic hemiparesis, dyarthria]
• Perforating arteries/ small artery disease

• POCS → Posterior Circulation syndrome
• Isolated Hemianopia/ brainstem syndrome
• Perforating arteries, PCA or cerebella arteries

• ECG → look for AF
• FBC → low PLTs cant give rTPA
• BM → hypoglycaemia can mimic stroke
• CT/ MRI → distinguish between ischaemic & haemorrhagic

• Admit Pt to stroke unit
• Thrombolysis <4.5hrs → Alteplase [rTPA]
• Exclude heamorrhagic on non contrast CT
• Antiplatelets after 24hr scan
• >4.5hr → antiplatelet therapy [300mg aspirin]

• Aspirin + dipyramidol/ clopidogrel
• Antihypertensives
• Cholesterol lowering therapy
• Warfarin if in AF
• Carotid Endartectomy → remove carotid stenosis

Sustained synchronised electrical discharge in brain causing symptoms/signs

• Status Epilepticus
• Seizure >30min
• Series of seizures w/o regaining consciousness [benzos/ anticonvulsants]

• A tendency to have recurrant unproveked seizures
• Imbalance of excitation & inhibition in brain

• Generalised Tonic-clonic
• Tonic phase → stiff, rigid muscles
• Clonic → dysrhythmic shaking **better define

• Partial Seizures w
• Loss of awareness
• Motor phenomena
• Sensory phenomena
• Psych phenomena
• Cognitive phenomena

• Hx
• Worse lying flat
• Worse in morning
• Persistant nausea & Vom
• Worse w exertion

• O/E
• Papilloedema
• CN6 signs
• CN3 signs
• Pain on valsalva

• Hx
• Worse sitting/ standing up
• Eased by lying flat
• Due to CSF leakage → traction of meninges → pain

• ICP = 7-15mmHg
• >25 = shit your pants time [Brain herniation]

• Causes
• Mass effect → space occupying lesion
• ^ venous pressure → cerebral sinus thrombosis
• Idiopathic → obese young women

• Oh PANTS!
• Older age onset
• Previous headaches = different/ absent
• Acute onset <5min → thunderclap
• Neurological signs/ Symptoms
• Triggered headache → valsalva/ postural
• Systemic symptoms

• Abrupt onset, reaching maximum severity in <5min
• Subarachnoid haemorrhage until proven otherwise