Neurological Flashcards
What would a patient with an oculomotor nerve palsy look like?
Unilateral complete ptosis
Eye down and out
Fixed dilated pupil in both direct and consensual light reflex (note opposite eye would dilate as consensual reflex still present)
If partial nerve palsy it would spare pupillary and lid parasympathetic nerves
Causes of optic nerve lesion
- optic/retrobulbar optic neuritis
Optic nerve compression eg pit tumour/aneurysm
Toxic/ischaemic/hereditary optic neuropathy
Vit B12 def
Trauma
infection
papilloedema
Causes of oculomotor nerve lesion
Aneurysm of posterior communicating artery
Internal carotid aneurysm
Microvascular infarction eg diabetes (spares pupil)
Midbrain infarction
Demyelination brainstem- MS
Myasthenia, orbital mass, inflammation
Causes of UMN facial palsy (spares forehead)
Stroke with hemiparesis on contralateral side Intracranial tumour MS Syphilis HIV
Causes of LMN facial palsy
Bells palsy Ramsey hunt syndrome Infection- lyme disease, TB otitis media skull # CPA tumours diabetes sarcoidosis Stroke- brainstem lesion demyelination-MS
Where is the damage in internuclear opthalmoplegia?
Damage to medial longitudinal fasciulus in brainstem and causes:
- disconjugate horizontal movements
- incomplete adduction of ipsilateral eye
- coarse jerky nystagmus of opposite abducting eye
Which nerves are affected in cavernous sinus syndrome and what are the symptoms?
Ipsilateral III, IV, VI, V1
Painful opthalmoplegia with fixed dilated pupil
Orbital congestion, chemosis, periorbital oedema
Proptosis
Sensory loss over V1 and possible horners
What causes cavernous sinus syndrome?
- tumours- nasopharyngeal/menigiomas
- pit apoplexy
- vascular- aneurysms of carotid, carotid sinus AV fistula, aseptic thrombosis
- infections
- granulomatous disease
What nerves are affected in Jugular foramen syndrome and what are the symptoms?
IX, X, XI Dysphagia, dysphonia Sensory loss of posterior 1/3 tongue, soft palate, larynx Sternocleidomasteoid/trapezius atrophy Absent gag reflex Headache/hydrocephalus/raised ICP
What nerves are affected in CPA syndrome? what are symptoms?
V, VII, VIII (less commonly VI, IV, X)
Facial sensory loss LMN facial weakness without hyperacusis Sensorineural hearing loss and tinnitus Nystagmus and gaze palsies If grows and puts pressure on cerebellum- ataxia
Which syndrome causes an ipsilateral 3rd nerve palsy and contralateral hemiparesis?
Weber’s syndrome
What are the differential diagnoses of stroke?
SOL: tumour, abscess, parasities Viral encephalitis Neuroinflammatory Metabolic Migraine Epilepsy- Todds paresis following a focal seizure Neuropsychiatric
What investigations would you do in a possible stroke?
Bloods: FBC, glucose, clotting, ESR, TFTs, ANA ECG- AF CT brain SALT review CXR- aspiration fasting glucose and lipids Thrombophilia screen MRI brain 24hr tape Carotid doppler
What is the acute management of stroke?
Confirm ischaemia
- Thrombolysis within 4.5hrs if no contraindications
- 300mg aspirin continued for 2 weeks
- If in AF wait 2 weeks until starting anti-coag
- Keep glucose 4-11mmol/L
- monitor BP- anti-hypertensives only given in hypertensive emergency eg encephalopthy, nephropathy, CCF
Who would be referred for hemicraniotomy?
Refer within 24hrs onset
Age <60yrs
Clinical deficits suggesting a MCA infarc with NIHSS score>15
Decrease in level of conciousness
Signs on CT of infarct of at least 50% MCA territory +/- additional territory of ant/post cerebral artery
Name some contraindications to thrombolysis?
Seizure at onset of stroke Symptoms suggestign SAH stroke/serious head injury in last 3 months Major surgery or trauma in last 2 weeks Previous intracranial haemorrhage Intracranial neoplasm AV malformation or aneurysm GI/urinary tract haemorrhage in last 3 weeks LP in preceeding week Current INR>1.7 Acute pericarditis Glucose <2.7 Preganancy
What are the acute and chronic complications of stroke?
Acute: raised ICP, haemorrhagic transformation, aspiration pneumonia
Chronic: pneumonia, contractures, DVT, pressure sores, UTI, constipation, depression, seizures, thalamic pain syndrome
What would you use in the secondary prevention of stroke?
Clopidogrel 75mg OD (if TIA on aspirin and dypyridamole)
Anticoagulation if in AF ( wait 2 weeks after stroke, start immediately if TIA)
Statin- aim to reduce non-HDL by 40%
Treat hypertension
LIfestyle- smoking, alcohol, exercise, diet
What score is used in strokes?
NIHSS (National institute for health stroke score)- used to assess severity of stroke and is scored out of 42.
Uses level of conciousness, gaze, visual field deficit, motor and sensory deficit, dysarthria, ataxia etc
WHat new interventional treatment for strokes is becoming available?
Mechanical thrombectomy- intra-arterial clot retrival via cannulation of femoral artery.
Used for people with proximal vessel occlusion.
NNT for 1 person to acheive functional independance is 2.6. Ideally done within 5hrs
How would you investigate and manage a patient with possible SAH?
- CT head- 95% accurate if done within 48hrs
- LP 12hrs later- xanthochromia
- Arterial imaging- CT/MR angiography
- supportive care- stabilise BP, ventilation, avoid hyperglycamia and hyperthermia
- stop anti-coagulation
- Commence nimodipine- reduce risk of vasospasm
- Liaise with neurosurgery- ? clipping/endovascular coiling
What are the clinical features of MS?
OPtic neuritis: pain behind eye on movement, reduction in visual acuity, colour desaturation, RAPD. Visual acuity reaches nadir at 2 weeks
Diplopia: VIth nerve palsy or INO
Spinal cord syndrome: sensory disturbance, paraparesis, bowel/urinary dysfunction
Weakness and spasticity =0 later
Cerebellar signs- unsual at presenations
Dysarthria, dysphagia, pain, trigeminal neuralgia
Lhermittes sign: electric shock on flexion of neck
Uhtoffs phenomonen: worsening symptoms with rise in body temp
What investigations would you request for a patient with possible MS?
ESR, ANA, ANCA, dsDNA, ENA, anti-phospholipid
MRI: classical peri-ventricular white matter lesions and involvement of corpus callosum. Other sites are juxtacortical white matter, brainstem, cerebellum, spinal cord
Visual and auditory evoked potentials
CSF- mild raised WCC, unmatched oligoclonal bands
What criteria can be used to diagnose MS without 2 episodes occuring?
Revised McDonald criteria using MRI evidence of active and previous lesion or further MRII showing new lesion 30 days apart
What is the management of MS?
Acute relapses- steroid therapy
Symptomatic mx: physio, OT, SALT, antispasmodics- baclofen, IM botox, catheter, oxybutanin, laxatives
Disease modifying therapy: 1st line- relapsing and remitting - Beta interferon - glatiramer acetate - dimethyl fumarate - alemtuzumab
2nd line
- natalixumab- several cases of PML causing death so limited to severe active disease
- Fingolimod- 1st oral therapy, prevents lymphocyte movement across blood brain barrier
- mitoxantrone
MS mimics/differentials?
Vasculitis: SLE, Sjorgrens, sarcoid, neuromyelitis optics
Vascular: TIA/stroke recurrent, CADISIL, Fabrys disease, antiphospholipis
Mitochondrial disease MELAS
Infection: lyme disese, HIV, encephalitis, syphilis, PML
Metabolic: B12 def
Leucodystrophies
What is the criteria for diagnosis of neuromyelitis optica/Devics disease?
Requires bilateral optic neuritis, myelitis and 2 of the following 3 criteria:
- Spinal cord lesion involving 3 or more spinal levels
- Initially normal MRI brain
- Aquaporin 4 positive serum antibody
Treat with IVIg and plasma exchange in acute setting and steroids and immunosuppression long term
Do you know any rating scales for disability in MS?
The expanded disability status scale (EDSS) most widely used and ranged from normal 0 to 10 (death due to MS), 5= ambulatory without aid or rest for 200m.
What are the causes of parkinsonism?
Idiopathic parkinsons disease Drug induced: neuroleptics, antiemetics, valproate Parkinsons plus syndromes: PSP, MSA, Corticobasal degeneration Dementia with Lewy bodies Toxins: MPTP, manganese, carbon monoxide Wilsons disease Normal pressure hydrocephalus Post traumatic Post encephalitic Vascular parkinsonism
Which signs point away from diagnosis of IPD?
Symmetry
Tardive dyskinesia (drug induced)
Early falls (PSNP)
Early autonomic disturbance (MSA)
Early dementia and visual hallucinations (LBD)
unilateral apraxia, alien limb, myoclonus, dystonic posturing (CBD)
What are the causes of chorea?
Huntingdons disease Wilsons disease Sydenhams chorea Drug induced: anticonvulsants, OCP Pregnancy Polycythaemia rubra vera Cerebral infarction Prion disease Other inherited neurological disorder: spinocerebellar ataxias, neuroacanthocytosis
What causes a cerebellar disorder?
Demyelination Vascular- infarction/haemorrhage Space occupying lesion Alcoholic degeneration Drugs esp carbamazipine, phenytoin, barbiturates Metabolic: B12, copper, vit E def Hypothyroidism Coeliac disease Genetic: spinocerebellar ataxias, Friedriechs ataxia, Ataxia telangiectasia, Von-hippel-lindau MSA with cerebellar features
What do you know about the genetics of spinocerebellar ataxias?
SCAs heterogenous group of AD genetic conditions causing degenerative cerebellar syndrome.
Mutations are trinucelotide CTG or CAG repeats, demonstrate antcipation.
What do you know about Miller-Fisher syndrome?
Autoimmune, usually post infective disorder
Opthalmoplegia, ataxia, loss of lower limb reflexes assoc with anti=GQ1b antibodies
What is subacute combined degeneration of the cord?
Symmetrical dysaesthesia, loss of posterior column sensory modalities and spastic quadra/paraparesis due to B12 def (usually seen in patients with pernicious anaemia)
What is the definition of spasticity and how is it different from other types of hypertonia??
Spasticity increased tone due to upper motor lesion which is velocity dependent (resistance increases with rate the muscle is stretched)- clasp knife. In contrast extrapyramidal syndromes the rigidity is constant throughout and not velocity dependent
How are spinal tumours classified according to their anatomical location?
Intradural tumours- intramedullary or extramedullary
- ependymomas- include astrocytomas, glioblastomas, haemangioblastomas, glial tumours, mets, cavernomas
Extradural tumours- mets
Do you know any of the features of HTLV-1 infection?
Tropical spastic paraparesis
T cell leukaemia/lymphoma
Peripheral sensorimotor neuropathy
Low grade myositis
Other features: arthritis, sicca syndrome, uveitus, alveolitis
What do you know about stiff person syndrome?
Rare auto-immune or even rarer paraneoplastic syndrome driven by anti-GAD antibodies. Rigidity of axial and sometimes lower limb muscles- can be mistaken for spastic paraparesis.
Treat with immunosuppression, plasma exchange
What is a bulbar palsy and what are the causes?
LMN lesion of lower cranial nerves
characterised by nasal speech, nasal regurgitation, tongue wasting & fasciculations, dysphagia and drooling
Causes: MG, MND, neuropathy, myopathy
What is pseudobulbar palsy and what are the causes?
UMN lesion affecting supply to tongue and oropharynx
characterised by spastic hoarse voice, slow tongue movements, assoc brisk facial reflexes, dysphagia and drooling
Causes: MS, brainstem stroke, MND
What is MND and what are the commonest types?
Progressive neuronal degenerative disease affecting the motor neurons (anterior horn cells) of spinal cord and motor cranial nuclei
- Amyotrophic lateral sclerosis- most common and has both UMN & LMN signs.
- Progressive bulbar palsy
- Primary lateral sclerosis (only UMN)
- Progressive muscular atrophy (only LMN)
Is MND inherited?
Majority are sporadic with 5-10% familial (20% are due to mutation in SOD1 gene)
How would you manage a patient with MND?
Supportive NIV SALT Psychological Riluzole- prolong life by 3m
What are the signs of syringomyelia?
Dissociated sensory loss- loss of pain and temp with preserved light touch, vibration and position sense.
Cape like distribution
Wasting and weakness of small muscles of hand
Lower limb reflexes are brisk and extensor plantars
Examine for Horners
What are your differential for absent ankle jerks and extensor plantar responses?
MND Friedrichs ataxia Subacute combined degeneration of spinal cord Syringomyelia Tumours involving conus and cauda Neurosyphilis
What are the causes of a radiculopathy?
Disc herniation- C6/7, L5/S1
Cervical/lumbar spondylosis with osteophyte formation
Spinal stenosis
Compression: nerve sheath tumours, epidural abcess
Inflammation: GBS
Infection: herpes zoster, CMV
Causes of brachial plexopathy?
Neuralgic amyotrophy (brachial neuritis)- inflammatory disorder of brachial plexus, severe pain and patchy weakness with winging of scapular
Neoplastic- lung and breast
Radiation induced
Thoracic outlet syndrome
Iatrogenic
Congenital brachial plexus injury- Erbs/Klumpkes palsy
Causes of lumbar sacral plexopathies?
Diabetic amyotrophy: subacute onset severe proximal leg and hip pain and weakness, not many/any sensory symptoms
Compressive lesion (haematoma, abscess, tumour)
Radiation induced
What are the causes of carpal tunnel syndrome?
Idiopathic Repetitive strain Pregnancy Hypothyroidism Diabetes Acromegaly RA Osteophytes/degeneration Gouty tophi Chronic renal failure- uraemia Multiple myeloma Hereditary neuropathy Amyloidosis Vasculitis
What are the causes of an ulnar nerve palsy?
Compression at elbow- crutches, perioperative
Bony deformity at elbow- osteophytes, #
Idiopathic
Diabetes
Hereditary neuropathy with liability to pressure palsies
Inflammatory neuropathies
Leprosy
What are the causes of peroneal nerve palsy?
Compression-plaster cast, tourniquet at fibula head
Direct trauma
Diabetes
Part of a mononeuritis multiplex: DM, Wegener’s, amyloidosis, RA, SLE, PAN
Leprosy (commonest cause worldwide)
How would you investigate a sensorimotor peripheral neuropathy?
Stage 1:
Urine: glucose and protein
Bloods: FBC, ESR, Vit B12, folate, fasting blood glucose, U+E, LFT, TFT
If clear cause eg diabetes or alcohol no need to investigate further
Stage 2: EMG and nerve conduction studies Serum protein electrophoresis, serum ACE Immunology: ANA, anti-RO, anti-LA, ANCA CXR
Stage 3: depends if neurophysiological test shows axonal (amplitude decreased, normal velocity) or demyelinating (normal amplitude, decreased velocity & prolongation of distal latency) Urine bence jones protein OGTT CSF: cells, protein, oligoclonal bands Immunology: anti-HIV antibiodies, antineuronal antibodies (Hu, Yo), antigliadin Test for sjorgrens Search for carcinoma, lymphoma Molecular genetic test
What is the differntial for a predominantly motor neuropathy?
Neuromuscular junction disorder- MG, Lambert eaton myasthenic syndrome
Distal myopathies: myotonic dystrophy, inclusion body myositis
What is the pathophysiology of myasthenia gravis?
Chronic autoimmune neuromuscular disease caused by antibodies directed against the acetylcholine receptors in muscle membrane
What antibodies are assoc with MG?
IgG Acetyl choline receptor antibodies in 75%
Anti-muscle specific kinase (MuSK) Ab: predominantly seen with facial, bulbar, resp weakness in young women
What are the clinical features of MG?
Thymectomy scar Ptosis Fatiguability Complex opthalmoplegia Pupillary reflexes normal Weakness of jaw, face, speech or swallowing muscles Proximal limb weakness Reflexes normal but may diminish with repetition
How would you investigate MG?
Serological test for AChR Ab and MuSK Ab
Tensilon test- not used anymore
Electrophysiological studies- repetitive stimulation and single fibre EMG
CT/MRI mediastinum- thymoma
What is the management of MG?
Assess resp function: FVC if <1.5l for HDU, if <1.2l for ITU
SALT
Avoid drugs that exacerbate: aminoglycosides, wuinine, beta blockers, phenytoin, penicillamine, anaesthetic agnets
Anti-cholinesterase inhibitors eg pyridostigmine
Corticosteroids- induce remission, can cause paradoxical worsening of MG in 1st 2 weeks so start in hospital
Immunomodulatory therapy: azathioprine, methotrexate, ciclosporin
IVIg or plasma exhange
Thymectomy
What is lambert- eaton syndrome?
Rare autoimmune syndrome characterised by impaired release of ACh from pre-synaptic membrane. Frequently assoc with malignancy (50%) or autoimmune disease (50%)
Antibodies against voltage gated calcium channels
What is the difference in symptoms between myasthenia or lambert eaton?
Lambert eaton rarely affects eyes
Myasthenia fatiguability, Lambert eaton gets better with use
Lambert eaton get autonomic symptoms
What are the neurophysiological findings in MG and LEMs?
Normal nerve conduction velocities (no demyelination)
Normal NMJ function there is natural decrement in total AcH release with each depolarisation but still far more than is required for adequate NMJ signal transmission
In MG- reduction in effective post synaptic receptor density results in failure of NMJ transmission and sequential reduction in amplitude of muscle reponse
In LEMS- repetitive stimulation at fast rate can facilitate neurotransmitted release resulting in increment response
What is single fibre EMG?
Measures difference in firing times between 2 fibres of same motor unit, increased variability of interval or jitter suggests NMJ transmission is abnormal
Investigation of choice for MG >95% sensitivity but not specific (also seen in MND, myositis and LEMs)
What is the role of thymectomy in MG?
CT/MRI mediastinum should be performed in all patietns with MG as 15% have a thymoma- most are benign but 10% malignant
All patients should have a resection and those with malignancy undergo radiotherpay
For patietns without thymoma the role of thymectomy is under debate, some evidence it increases probability of transmission and is recommended in seropositive with generalised disease under 60.
MuSK positive MG does NOT respond to thymectomy
What underlying malignancy is assoc with LEMs
Commonly SCLC
Also lymphoproliferative disorders, thymoma, carcinoma of breast, stomach, prostate, kidney, bladder
What are differentials of a distal >proximal myopathy?
Inclusion body myositis- flexors of forearm and quads
Fascioscapulohumeral dystrophy
Myotonic dystrophy
What are the differentials of facial myopathy with external ocular involvement?
Myopathy due to Graves disease
Mitochondrial disorders
Oculomusculopharyngeal dystrophy
Consider MG
What are the differentials of facial myopathy without external ocular muscle involvement?
Myotonic dystrophy
Facioscapulohumeral dystrophy
What are the features of myotonic dystrophy?
Myotonia: failure of relaxation of voluntary contraction, prolonged contraction after handshake Frontal balding Early ptosis Wasting sternocleidomastoid Weakness distal > proximal Wasting of pre-tibial muscles with foot drop Voice may be weak, monotonous Low IQ Cataracts Diabetes Testicular atrophy Cardiac involvement: bradycardia, AV block, CCF Wheelchair dependent within 15-25yrs
How is myotonic dystrophy inherited?
AD
Unstable trinucleotide repeats (CTG) on chromosome 19q (DMPK gene)
What are the features of Duchanne muscular dystrophy?
Proximal leg muscle weakness Low IQ Macroglossia Calf pseudohypertrophy cardiomyopathy resp failure Osteoporosis and scoliosis
What is the inheritance and how would you diagnose Duchanne and Becker muscular dystrophy?
X-linked
Duchanne: mutation in dystrophin gene
Becker: mutation in dystrophin gene but present just abnormal
CK very high
Dystrophin gene test
What are the signs of facioscalpulohumeral dystrophy?
Facial weakness- difficulty closing eyes, pursing lips
Difficulty raising arms above head
Winging of scapula
Triceps more wasted then biceps with relative preservation of deltoid
Pectoralis major weakness leads to reversal anterior axillary fold
What antibodies are found in dermatomyositis and polymyositis?
Dermatomyositis
ANA often positive
Anti-Mi-2 specific but only found in 25%
Polymyositis
Anti-Jo-1
What is inclusion body myositis?
Occurs most commonly in Caucasian males in later life
Indsidious onset, classic pattern of weakness involving quadriceps and deep finger flexors
OCcasional dysphagia, foot drop
Not thought to be related to malignancy
Can look similar to predominantly LMN MND
How would you investigate a possible myopathy?
FH and drug history
Blood test confirm raised CK
ESR, FBC< U+E, LFT, bone profile, glucose, TFT, ANA, ANCA, RF/anti-CCP
EMG- to determine presence of myopathic changes
CXR+ ECG + ECHO
Dermatomyositis look for underlying malignancy with CT CAP /PET
What features of EMG would suggest myopathy?
Myopathies produce damage to muscle fibre membrane, resulting in influx of sodium that can occasionally cause muscle fibre to depolarise resulting in fibrillation and positive sharp waves.
In myopathies each motor unit supplies fewer muscle fibres with noraml function, smaller potentials and conduction in abnormal muscle fibres in dispersed and so motor potentials are also polyphasic but of short duration and amplitude
What are the treatments for inflammatory myopathies
Steroids
Steroid sparing agents: azathioprine, methotrexate, ciclosporin, cyclophosphamide, IV Ig
What patients are at increased risk of statin-induced myopathy?
8 x increase myopathy in patients taking statins
42 x increase if fibrate co-administered
Risk is dose related but higher in elderly, diabetics, hypothyroidism, renal/liver disease
Drugs eg ciclosporin, PPIs, CCBs, SSRIs, grapefruit
Do not routinely check CK unless symptomatic
How would you investigate somebody presenting with a first seizure?
FBC, U+E, LFT Electrolytes Blood glucose CXR CT head + MRI later ECG EEG
When would you consider starting anti-epileptics after one seizure?
- the child, young person or adult has a neurological deficit
- the electroencephalogram (EEG) shows unequivocal epileptic activity (for more information on using EEG to diagnose epilepsy, see EEG in this pathway)
- the child, young person or adult and/or their family and/or carers consider the risk of having a further seizure unacceptable
- brain imaging shows a structural abnormality (for more information on imaging, see imaging in this pathway).
What anti-epileptics are used in generalised tonic-clonic seizures?
1st line sodium valproate (teratogenic)
2nd line lamotrigine or carbamazipine
What anti-epileptics are used in absence seizures?
Ethosuximide or sodium valproate
Dont use carbamazipine
What anti-epileptics are used in myoclonic seizures?
Sodium valproate
Consider topiramate or levetiracetam
Dont use lamotrigine or carbamazepine
What anti-epileptics are used first line in focal seizures?
Carbamazipine or lamotrigine
2nd line levetiracetam or valproate
What are the signs of a spinal cord disorder?
Paraparetic spastic gait Spasticity of lower limbs Pyramidal weakness Upgoing plantars Sensory level above L1 Catheter Spinal surgery scars
What would sparing of the posterior column suggest?
Vibration, proprioception and light touch are preserved in:
- anterior cord infarction
- syrinx
What would predominant loss of posterior column suggest?
B12 def
Neurosyphilis
HIV assoc myelopathy
What categories can you split spinal cord disorders into and give some examples?
Compressive: degenerative- disc hernation, tumour, trauma, infection- abcess, haematoma
Vascular: spinal artery infection, AVM
Inflammatory: transverse myelitis- MS, SLE, Devics disease, paraneoplastic
Infection
Nutritional/toxic: subacute combined degeneration of spinal cord, copper def
Degenerative/herediatary- hereditary spastic paraparesis (AD/AR/X linked), Freidrichs ataxia, Spinocerebellar ataxias
How would you manage somebody with Parkinsons disease?
MDT approach- OT, physio
SPecialist nurse
Drugs
- Dopamine agonists- ropinerole, pramiprexole
- Levodopa
- MAOIs: selegaline
- Amantidine
(don’t use ergot derived dopamine agonists)
What is the pathophysiology of Parkinsons syndrome?
Characterised by degeneration of substantia nigra causing loss of dopamine in the striatum.
What is the pathophysiology of Huntingdons disease?
Chorea results from damage to neurons (GABA, encephalin) in indirect pathway from striatum to globus pallidus resulting in increased signals to thalamus leading to increased cortical activity
How can you classify movement disorders?
Insufficient movement
Akinetic, hypokinetic or bradykinetic syndromes
Too much movement (hyperkinesias or dyskinesias)
Jerky movements
■ Myoclonus (including excessive startle)
■ Chorea (including ballism)
■ Tic disorders
Non-jerky movements
■ Dystonia (including athetosis)
■ Tremor
Where does the oculomotor nerve originate?
Midbrain
edinger westphal nucleus- parasympathetic fibres
Where is trochlear nerve nucleus?
Dorsal midbrain
Where is the abducens nerve nucleus?
Pons with facial nerve
What are the causes of mononeuritis multiplex?
Most common cause is vasculitis
Autoimmune problems: SLE, RA
If you find an ipsilateral cerebellar lesion, what should you look for?
A scar when unilateral, causes differ from bilateral
If you suspect parkinsons disease, how would you fully examine the patient?
Asymmetrical tremor- ask patient to make movements with contralateral hand or count backwards from 100 to see if this worsens
Bradykinesia: repetitive pincer grip motions or pronate/supernate hands
Micrographia- drawing if required
Test for parkinsons + syndromes
How would you examine somebodies speech?
Assess understanding eg touch your right ear with your left hand and touch your nose- tests “receptive dysphasia”
Assess word formation- ask if they have trouble finding the right words- “expressive dysphasia”
Articulation:
Baby hippopotamus for lip sounds - CN VII
Grey geese for palatal sounds- CN IX, X
Red lorry, yellow lorry for tongue sounds - CN XII
What are your differentials of an UMN mono or hemiparesis?
Stroke (anterior cerebral artery will affect legs more than arms and MCA opposite)
Space occupying lesion eg tumour
Demyelination
Rarely brown sequard syndrome- trauma, tumour, abcess
Causes of spastic parapesis
If sensory level then spinal cord lesion or compression- look for scar
If normal sensation consider hereditary spastic paraparesis
If ataxia consider MS and Friedrichs ataxia/spinocerebellar ataxias
- Demyelination/MS
- Cerebral palsy
- Transverse myelitis
- MND: mixed UMN and LMN, normal sensation
- cord compression: cervical myelopathy, tumour
- syringomyelia- preserved dorsal column
- anterior spinal artery infarction
- tropical spastic paraparesis
- bilateral stroke
- hereditary spastic paraparesis
Causes of a flaccid paraparesis?
Cauda equina
Absence of sensory signs: GBS, CIDP, motor neuropathy or MND
What are the causes of proximal weakness
Metabolic/endocrine myopathies eg hypothyroidism
Inflammatory myopathies eg polymyositis/dermatomyositis
Dystrophies- Duchanne
Congenital metabolic myopathies: McArdles
Toxic/drug induced myopathies: alcohol/statins
Myasthenia gravis
Lambert eaton syndrome
Idiopathic
Cord lesion
