Neurology PDF

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Summary

Comprehensive notes on neurology, everything that can be tested on by UCL for the MBBS course. Organised by condition, with a description, aetiology, signs and symptoms, investigations, management and more for each condition...

Description

Neuroscience

CONDITIONS Neuro

LOCALISE THE LESION................................................................................................................................... 2 CEREBROVASCULAR DISEASE..................................................................................................................... 4 TRANSIENT ISCHEMIC ATTACKS (TIA)................................................................................................................................4 ISCHEMIC STROKE............................................................................................................................................................6 HYPOXIC ENCEPHALOPATHY.............................................................................................................................................9 WATERSHED INFARCTION.................................................................................................................................................9 HAEMORRHAGIC STROKE.................................................................................................................................................9 STROKE: TERRITORIES.....................................................................................................................................................11 CEREBELLAR DISEASE.....................................................................................................................................................13 MOTOR DEFECTS............................................................................................................................................................13 BRAIN BLEEDS.............................................................................................................................................. 13 EXTRADURAL HAEMORRHAGE (epidural).......................................................................................................................13 SUBDURAL HAEMORRHAGE...........................................................................................................................................14 SUBARACHNOID HAEMORRHAGE..................................................................................................................................16 DEMENTIA....................................................................................................................................................... 18 ALZHEIMER’S DISEASE....................................................................................................................................................19 VASCULAR DEMENTIA....................................................................................................................................................21 LEWY BODIES DEMENTIA...............................................................................................................................................22 FRONTOTEMPORAL DEMENTIA......................................................................................................................................23 DEGENERATIVE DISORDERS.......................................................................................................................24 HUNTINGTON DISEASE...................................................................................................................................................24 PARKINSON’S DISEASE....................................................................................................................................................26 PARKINSON’S PLUS SYNDROMES....................................................................................................................................29 ESSENTIAL TREMOR........................................................................................................................................................30 MOTOR NEURONE DISEASE............................................................................................................................................30 PRION DISEASE...............................................................................................................................................................32 INCREASED INTRACRANIAL PRESSURE....................................................................................................32 RAISED INTRACRANIAL PRESSURE (ICP)..........................................................................................................................32 IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH)...........................................................................................................33 HYDROCEPHALUS...........................................................................................................................................................34 BRAIN TRAUMA + DAMAGE............................................................................................................................................36 INTERNAL HERNIATION..................................................................................................................................................38 INFECTION...................................................................................................................................................... 38 BACTERIAL MENINGITIS..................................................................................................................................................38 VIRAL MENINGITIS..........................................................................................................................................................41 FUNGAL MENINGITIS......................................................................................................................................................42 BACTERIAL BRAIN ABSCESS............................................................................................................................................44 ENCEPHALOPATHY....................................................................................................................................... 44 ENCEPHALITIS.................................................................................................................................................................45 WERNICKE’S ENCEPHALOPATHY.....................................................................................................................................46 TUMOURS....................................................................................................................................................... 48 CENTRAL NERVOUS SYSTEM (CNS) TUMOURS...............................................................................................................48 HEADACHES................................................................................................................................................... 50 MIGRAINE.......................................................................................................................................................................50 TENSION HEADACHE......................................................................................................................................................52 CLUSTER HEADACHES.....................................................................................................................................................53

Neuroscience

CONDITIONS

OTHER............................................................................................................................................................................ 54 SEIZURE DISORDERS.................................................................................................................................... 55 EPILEPSY.........................................................................................................................................................................55 PHENYTOIN.....................................................................................................................................................................60 VASOVAGAL SYNCOPE....................................................................................................................................................61 CARDIAC SYNCOPE.........................................................................................................................................................62 BRAIN STEM (Cranial nerves)....................................................................................................................... 63 BELL’S PALSY...................................................................................................................................................................63 TRIGEMINAL NEURALGIA...............................................................................................................................................65 HORNER’S SYNDROME...................................................................................................................................................66 DEMYELINATION............................................................................................................................................ 67 GUILLAIN-BARRE SYNDROME.........................................................................................................................................67 MULTIPLE SCLEROSIS...................................................................................................................................................... 69 TRANSVERSE MYELITIS................................................................................................................................................... 71 SPINAL CORD PATHOLOGY.......................................................................................................................... 72 SPINAL CORD INJURY / TRUAMA....................................................................................................................................72 SPINAL CORD COMPRESSION.........................................................................................................................................72 CAUDA EQUINA SYNDROME...........................................................................................................................................74 RADICULOPATHY.............................................................................................................................................................76 NEUROPATHY................................................................................................................................................. 77 PERIPHERAL NEUROPATHY.............................................................................................................................................77 CHARCOT-MARIE-TOOTH DISEASE..................................................................................................................................78 AUTONOMIC NEUROPATHY............................................................................................................................................78 FUNCTIONAL NEUROLOGICAL DISORDER.......................................................................................................................79 NEUROMUSCULAR JUNCTOIN.....................................................................................................................80 MYASTHENIA GRAVIS......................................................................................................................................................80 EXTRA............................................................................................................................................................. 82 DVLA: NEUROLOGICAL DISORDERS................................................................................................................................82 GLASGOW COMA SCALE.................................................................................................................................................83 LUMBAR PUNCTURE.......................................................................................................................................................83 CENTRAL VENOUS CATHETERISATION............................................................................................................................84

LOCALISE THE LESION CNS  Brain o Cerebral hemispheres  two hemispheres with four lobes  Motor cortex (mainly in pre-central gyrus) o Basal ganglia o Cerebellum o Brain stem  Spinal cord  cervical, thoracic, lumbar o Spinal cord ends at L1 and cauda equina starts afterwards Peripheral nervous system 1. Anterior horn cell (embedded int the spinal cord)

Neuroscience

CONDITIONS

2. Nerve root 3. Plexus 4. Peripheral nerve 5. NMJ 6. Muscle Cranial nerves  Originate in the brainstem (so when there's a brainstem pathology - will see CN affected) o CN I  not brain stem o CN II is a bit different from the others  doesn't have nucleus and axon like the others, is actually part of CNS - is white matter of the brain o CN III, IV  originate from midbrain o CN V, VI, VII  originate from pons o CN VIII  originate from junction of pons and medulla o CN IX, X, XI, XII  originate from medulla  Cranial nerves are LMN o Dual innervation of CNs from both hemispheres - so when there's a stroke/unilateral lesion in cortex  won't show any CN problem o CN VII is exception  CN VII: o Upper part of face has dual innervation from both hemispheres (stroke is forehead-sparing) o Lower part of face only has contralateral innervation from one hemisphere  so the pattern of weakness is similar to what happens in the limbs Localising the lesion:  If there's UMN weakness in arms and legs but CN intact  lesion must be below the brainstem o If CN involved  brainstem pathology  Disc compression/spinal pathology o May have LMN signs at that level  Due to how the PNS originates in the CNS - the anterior horn cell is in the spinal cord  therefore if anterior horn or exiting nerve routes are damaged get LMN at level of lesion o UMN signs below that level  Single lesions that affect both sides of the body:  Brainstem lesion  Spinal cord lesion o Distinguish by checking if there's CN involvement Other symptoms  Dysphonia  problem with volume (resp muscles or vocal cords)  Dysarthria  problem with articulation  Dysphasia o Expressive (Broca’s)  they can carry out your instructions but can’t find the words to as motor area affected o Receptive (Wernicke’s)  inability to understand speech, but produce fluent non-sensical speech

Neuroscience

CONDITIONS

Pathology  Systemic  Metabolic, toxic, nutritional, immunological, endocrinology  Vascular  Haemorrhagic, infarct  Intrinsic  Metabolic, infectious, neoplastic, degenerative, paroxysmal, immunological, genetic Signs Muscle bulk Weakness Fasciculation Clonus Tone Reflex Bladder Hoffmann’s reflex (finger flexor reflex) Babinski reflex (extensor plantar reflex)

UMN involvement Grossly normal Mild to moderate Pyramidal + asymmetrical Absent Present Hypertonia (spasticity) Brisk Urinary retention (dilated bladder) Present

LMN involvement Atrophic + wasting Severe Distal + symmetrical Present Absent Hypotonia Reduced or absent Urgency (Spastic bladder) Absent

Present

Absent

LMN:

Pathology UMN Stroke Multiple sclerosis Traumatic brain injury Cerebral palsy MND (amyotrophic lateral sclerosis) SOL – tumour, bleed Hemiplegic migraine

LMN Guillain bare syndrome Cauda equine syndrome Polio Myasthenia gravis MND (can cause both) Muscular dystrophies Neuropath’s

Neuroscience

CONDITIONS

CEREBROVASCULAR DISEASE TRANSIENT ISCHEMIC ATTACKS (TIA) Define Transient episode of neurological dysfunction caused by focal brain, spinal cord or retinal ischemia, without acute infarction Most resolve within an hour, but all are resolved within 24 hours Aetiology/risk factors  Most cases are due to underlying cerebral atherosclerosis  Can also be thrombosis in situ of an intracranial artery  Or extracranial embolisms  o Cardiac emboli  AF, endocarditis, MI, carotid dissection, valve disease, atrial myxoma, FPO o Large vessel atherosclerosis  aortic arch plaque, carotid stenosis, intracranial stenosis (affects the medium and large vessels of the brain) o Venous disease  DVT Risk Factors  Older age, FHx, African American or Hispanic ethnicity  Previous TIA or stroke  HTN (most important risk of stroke)  Hyperlipidaemia, DM, smoking, excessive alcohol intake, obesity, OCP  Heart disease  valvular ischemia, AF  Peripheral vascular disease + carotid artery stenosis  Hyperviscosity  sickle cell anaemia, polycythaemia vera Epidemiology Reasonably common. More common with increasing age (mean age is 72) and in men Symptoms and signs  Sudden onset of symptoms  within seconds  Brief duration of symptoms  10-15 mins o Although can be anything from a few minutes to 24 hours  Focal neurological deficit  o Unilateral weakness or numbness o Sensory, visual or cognitive impairment  Vision loss, transient aphasia, or vertigo o Impaired coordination + consciousness, can get light-headedness and dizzy  Neurological examination may be normal  TIA may have resolved Investigation  Clinical diagnosis + examination  To find underlying cause: o Bloods  FBC, U&E, glucose, clotting profile, cardiac enzymes, lipids  Hypoglycaemia can mimic TIA + electrolyte abnormalities can mimic weakness o ECG  check for AF, arrhythmias or ischemia  Holter monitoring for 24hours / depending on patient history o Echo  look for heart abnormalities (clot, left atrial enlargement, left ventricular hypertrophy, signs of old infarct, ASD, patent foramen ovale)

Neuroscience

CONDITIONS

o Carotid Doppler ultrasound  carotid artery stenosis o Transcranial Doppler ultrasounds  intracranial artery occlusion or critical stenosis o CT or MRI cerebral angiogram  intracranial occlusion, stenosis or dissection (done after carotid doppler to evaluate the stenosis seen there) Management At presentation  Aspirin 300mg as soon as possible, for 2 weeks, unless  o Patient has bleeding disorder or on warfarin (immediate imaging to exclude haemorrhage) o Patient is already taking low-dose aspirin regularly  Continue current dose until reviewed by a specialist o Aspirin is contraindicated  discuss management urgently with the specialist team  Admit urgently if  More than 1 (crescendo TIA) or severe carotid stenosis  Refer to see specialist within 24 hours if  TIA in the last 7 days  Refer to see specialist within 7 days if  TIA was >7 days previous to presentation  Assessment of future stroke risk in TIA patients  ABCD2 score  Further management  Lifestyle modifications  weight loss, exercise, stop smoking o Cannot drive until being treated (advise until TIA clinic decide)  Antiplatelet therapy  Clopidogrel 75mg after 2 weeks, given for life o If not tolerated, aspirin + dipyridamole o If AF warfarin or DOAC  Statin therapy (lipid lowering agents)  Atorvastatin 80mg, simvastatin, lovastatin  If >70% carotid stenosis  carotid endarterectomy or stent as blood clots can form on the stenosis and break off to cause a TIA or stroke o Carotid endarterectomy  surgeons open the artery and remove the plaque, then the artery is closed with a patch or stitches  If high BP  antihypertensive + lifestyle modification  If cardio-embolic TIA  anticoagulation (warfarin, rivaroxaban)  Glycaemic control if necessary Complications Recurrence, MI, stroke Prognosis Very high risk of stroke in the first month after the TIA (10% will have a stroke within 3 months) and up to 1 year afterwards

ISCHEMIC STROKE Define  An acute focal neurological disturbance of cerebrovascular origin lasting >24hrs  80% of strokes are ischaemic  blockage of blood flow so ...