Neurology & Special Senses Block Flashcards
What are the components of a systems review from a neurological point of view? (8)
- Vision
- Smell
- Taste
- Headache
- Fits, faints, funny turns
- Hearing
- Speech + swallow
- Sensation
- Balance + coordination
- Incontinence/erectile dysfunction
- Memory
What are 4 important aspects to focus on in a neurological history?
- Timeline of symptoms in presenting complaint
- Neurological systems review
- Detailed family history of multiple generations
- Determining the impact of the disease on patient’s life
What 3 symptoms are associated with cluster headaches?
- Eye watering
- Eye infection
- Nasal congestion
**Unilateral autonomic involvement
What 4 symptoms are associated with migraine?
- Photophobia
- Aura symptoms
- Phonophobia
- Nausea/vomiting
What is the headache differential for:
Tight, band-like sensation, precipitated by stress
Tension headache
What is the headache differential for:
Brief, stabbing pain when brushing teeth or chewing
Trigeminal neuralgia
What is the headache differential for:
Photophobia, neck stiffness, fever
Meningitis
What is the headache differential for:
Sudden onset, excruciating headache
Subarachnoid hemorrhage
What is the headache differential for:
Facial tenderness, rhinorrhea
Sinusitis
What is the headache differential for:
Unilateral, pounding, multiple triggers, lasts for hours, aversion to bright lights and loud noises, can be preceded by aura
Migraine
What is the headache differential for:
20min unilateral, debilitating episodes of retro-orbital pain with red eye + eye watering
Cluster headache
What is the headache differential for:
Headache triggered by changes in position/exertion, Changes in vision with leaning forward
Increased intracranial pressure
What is the headache differential for:
Pain around eye, blurred vision with halos around lights
Acute glaucoma
What is the headache differential for:
Scalp tenderness, unilateral, jaw claudication
Temporal arteritis
What are the NICE Guidelines headache red flags? (10)
- Sudden onset high severity headache
- Headache with fever
- New onset neurological deficit
- New onset cognitive dysfunction
- Change in personality
- Impaired level of consciousness
- Recent head trauma (within past 3mo)
- Headache triggered by cough, sneeze, exercise, or changes in posture
- Headache associated with halos around lights, or headaches that get worse in the dark
- Headache associated with jaw claudication + scalp tenderness
What is the acute and prophylactic treatment used for cluster headache? (2)
Acute = 100% high flow oxygen (12L/min) with non-rebreathe mask + reservoir bag
Prophylactic = Verapamil
What is the acute and prophylactic treatment used for migraine? (4)
Acute = NSAIDs, Paracetamol, Oral triptan
Prophylactic = Propranolol
What is the loss of consciousness differential for:
Triggered by suddenly standing up
Postural hypotension
What is the loss of consciousness differential for:
Chest pain, breathlessness, and collapse on exertion
Aortic stenosis
What is the loss of consciousness differential for:
Palpitations/chest pain beforehand, family history of sudden unexplained death
Arrhtyhmia/cardiogenic syncope
What is the loss of consciousness differential for:
Triggered by fear, pain, micturition, or prolonged standing. Preceeded by pallor, nausea, or sweating. No confusion afterwards
Vasovagal syncope
What is the loss of consciousness differential for:
Triggered by vigorous exercise in a young person
Hypertrophic cardiomyopathy/cardiogenic syncope
What is the loss of consciousness differential for:
Collapse on shaving or turning head
Carotid sinus hypersensitivity
What is the loss of consciousness differential for:
Being told off by teachers for seemingly daydreaming
Absence seizure
What is the loss of consciousness differential for:
Pale and sweaty beforehand, jerking of limbs, eyes rolled back, short duration of episode, no confusion afterwards
Vasovagal syncope
What is the loss of consciousness differential for:
Twitching and jerking in the morning
Early morning myoclonus
What is the loss of consciousness differential for:
Crying out, falling to the floor, period of stiffness followed by rhythmic jerking that gradually decreases in amplitude and frequency, period of confusion for 30min afterwards
Generalised tonic-clonic seizure
What is the loss of consciousness differential for:
Violent shaking, head moving side to side, arching back, episodes of stillness before starting again, forced eye closure
Psychogenic non-epileptic attack
Give 2 examples of LMN pathology that can be seen at the end of the bed when examining the patient?
- Fasciculations
2. Muscle atrophy
What does a pale optic disk indicate? (1)
Previous optic neuropathy
What does the swinging torch test assess? (1)
Relevant Afferent Pupillary Defect (RAPD)
What is a Relevant Afferent Pupillary Defect?
Paradoxical pupil dilatation observed in the affected eye
sign of damage to the optic nerve of the affected eye, which indicates optic neuropathy
What are saccades?
Rapid eye movements between 2 targets
What pathology can cause slow/restricted saccades? (1)
Progressive supranuclear palsy
What nerves are assessed in the corneal reflex test? (2)
- Trigeminal nerve (CN 5) = afferent
2. Facial nerve (CN 7) = efferent
Give 2 examples where you’d observe weakness of the facial nerve (CN 7) in a neurological examination?
- Bell’s palsy (LMN - facial paralysis)
2. Stroke (UMN - forehead sparing due to bilateral innervation)
What nerves are tested in the gag reflex? (2)
- Glossopharyngeal nerve (CN 9) = afferent
2. Vagus nerve (CN 10) = efferent
What does pronator drift indicate? (1)
UMN lesion in pyramidal tracts
When assessing tone in a patient, what is the difference between spasticity and rigidity, and give 1 example of a condition with each?
Spasticity = stiffness exacerbated when attempting to move the limb quickly (i.e. pyramidal lesion = UMN pathology)
Rigidity = stiffness that remains throughout entire movement (i.e. extrapyramidal lesion = PD)
In what situations are reflexes exaggerated? Decreased/absent? (2)
Exagerrated = UMN pathology
Decreased/absent = LMN pathology
What 2 tests done in a neurological examination assess the dorsal columns?
- Proprioception test
2. Vibration test
What tests are done in a neurological examination to assess the spinothalamic pathway? (2)
- Pinprick test
2. Sensation with cotton wool
What additions would need to be made to the basic neurological examination in a patient with suspected Parkinson’s disease? (4)
- Observe for “pill-rolling tremor” (easiest to visualize with a distracting task - get pt to close eyes + count down from 20)
- Bradykinesia: check speed of movement with finger snapping
- Check face for hypomimia (expressionless face)
- Check gait for reduced stride length, reduced arm swing, broken turning
How is muscle power assessed using the MRC Grading Scale? (6)
0 = no power 1 = twitching but no movement 2 = movement, but cannot overcome gravity 3 = can overcome gravity 4 = movement against gravity and resistance 5 = normal muscle strength
What structures are considered upper motor neurone? (3)
CNS structures:
- Motor cortex
- Spinal cord
- White matter tracts
What structures are considered lower motor neurone? (4)
PNS structures:
- Motor nerve
- Nerve root
- Neuromuscular junction
- Anterior horn cell
What are signs of UMN pathology? (4)
- Hypertonia
- Atrophy
- Positive Babinksi sign
- Hyperreflexia
What are signs of LMN pathology? (4)
- Hypotonia
- Atrophy
- Fasciculations
- Hyporeflexia
Where do motor nerve pathways cross? (1)
Crosses in the medulla
What is a hemi-section of the spinal cord also referred as? (1)
Brown-Sequard syndrome
What motor symptoms would you expect to see in Brown-Sequard syndrome? (2)
UMN signs b/c damage to the spinal cord:
- Increased tone
- Increased reflexes
Signs will be seen in areas distal to the level of the lesion, and on the ipsilateral side
What sensory symptoms would you expect to see in Brown-Sequard syndrome? (2)
- Loss of vibration, fine touch, proprioception (ipsilateral to lesion)
- Loss of temperature and pinprick (contralateral to lesion)
In homonymous hemianopia, where is the nerve damage? (2)
Occipital cortex or optic radiation
In bitemperal hemianopia, where is the nerve damage? (1)
Optic chiasm
In monocular blindness, where is the nerve damage? (1)
Optic nerve
Where does the dorsal columns pathway cross? (1)
Medulla
Where does the spinothalamic pathway cross? (1)
Spinal cord
What are the main investigations used in neurology? (5)
- CT: identifying acute collections of blood (i.e. SAH, extradural hematoma)
- MRI: looking for lesions (i.e. MS, tumours)
- Lumbar puncture: looking for infection/inflammation (i.e. meningitis, encephalitis)
- EEG (electroencephalography): (i.e. seizures, encephalopathy)
- Nerve conduction studies/electromyography (EMG): assess neurological structures in PNS
A 65 year old male is being reviewed on the stroke ward after returning from radiology. Imaging reveals an ischemic stroke involving the left temporal lobe.
What visual field defect would most likely be found upon examination?
R superior quadrantanopia
What investigations would you order for a patient with four limb weakness with breathlessness? (10)
- FBC
- U&E
- LFTs, Calcium, Magnesium, Phosphate
- CRP
- ESR
- Chest x-ray
- Basic spirometry
- ECG
- Lumbar puncture
- MRI of spine
What is the first line treatment for Guillain-Barré syndrome? (3)
- IV immunoglobulin
- Thromboprophylaxis (TEDs + LMW heparin)
- Plasma exchange (technically demanding)
What are complications of lumbar puncture? (7)
- Headache (common)
- Painful paraesthesia
- Persistent pain/paraesthesia
- Bleeding
- Infection (meningitis)
- Uncal herniation
- Failure of procedure
What are 3 causes of a genuine dry tap when performing a lumbar puncture? (3)
- Arachnoiditis
- Meningeal infiltration
- True low CSF pressure
At what level is a lumbar puncture performed? (2)
- Between L3-L4
2. Between L4-L5
What lumbar puncture result would suggest Guillian-Barré syndrome? (1)
Normal cell count but elevated protein level (‘cytoalbuminologic dissociation’)
What are the 6 Guillian-Barré syndromes?
- AIDP (acute inflammatory demyelinating polyradiculoneuropathy)
- AMAN (acute motor axonal neuropathy)
- AMSAN (acute motor + sensory axonal neuropathy)
- Miller-Fisher syndrome
- Pure sensory neuropathy
- Acute pandysautonomia
What are the 5 features that all Guillian-Barré syndromes have in common?
- Acute/sub-acute, monophasic PNS disorders (peak disability <4 weeks; 4-8 weeks)
- Antecedent “trigger”
- Areflexia
- CSF “albuminocytologic dissociation” (increased protein with normal cell count)
- Generally spontaneous recovery occurs
What are the features of AIDP (Guillian-Barré syndrome)? (5)
- Begins with paraesthesia + pain (50%)
- Followed by muscle weakness first in legs (10% in arms first)
- Facial nerve commonly involved + ophthalmoplegia
- Autonomic manifestations (labile BP, arrhythmia, constipation, abdominal distention)
- Progresses days to 4 weeks
How is Guillian-Barré syndrome diagnosed? (2)
- CSF “albuminocytologic dissociation”
2. Nerve conduction studies (increased F-wave latency)
What is the pathophysiology of Guillian-Barré syndrome? (1)
Demyelination of peripheral nerves
What can trigger Guillian-Barré syndrome? (4)
- Infections (CMV, HIV)
- Systemic illnesses (Hodgkin’s disease)
- Bacterial + Parasites (Campylobacter Jejuni)
- Other medical conditions (Pregnancy, surgery)
What is the most common form of Guillian-Barré syndrome in the developed world?
AIDP (acute inflammatory demyelinating polyradiculoneuropathy)
What is the prognosis of Guillian-Barré syndrome? (3)
- Mortality 3-5%
- 15% severe disability
- 80% recover within 6mo
What are 4 general indications for a lumbar puncture?
- Headache
- Infection (i.e. meningitis)
- Inflammation (i.e. transverse myelinitis, Guillian-Barré)
- Cancer
What are the 5 key measurements of CSF, and what are their normal levels?
- Opening pressure (only accurate when pt lying laterally on couch) = <20cm
- White cell count = <5WBC
- Red cell count = none
- Protein = <0.45g/L
- Glucose = approx 2/3 of plasma (check plasma glucose at same time)
What are 6 extra tests that can be performed with a lumbar puncture?
- Microbiological stains
- Culture + sensitivity
- Viral/bacterial PCR
- Oligoclonal bands (MS)
- Cytology
- Spectrophotometry/xanthochromia (SAH)
What do the key measurements of CSF look like in a bacterial infection? (4)
- High opening pressure
- Neutrophils present
- High protein
- Low glucose
What do the key measurements of CSF look like in a viral infection? (4)
- Normal opening pressure
- Lymphocytes present
- High protein
- Normal glucose
What do the key measurements of CSF look like in a TB infection? (4)
- High/very high opening pressure
- Lymphocytes present
- High/very high protein
- Very low glucose
What do the key measurements of CSF look like in a fungal infection? (4)
- Very high opening pressure
- Lymphocytes present
- High protein
- Low glucose
What would the CSF analysis look like in cancer? (3)
- High WBC + protein
- Very low glucose
- Abnormal cytology
What would the CSF analysis look like in subarachnoid hemorrhage? (2)
- High RBC
2. Xanthochromia (raised bilirubin + oxyhemoglobin)
In what infection do you see raised RBC count (hemorrhagic CSF)?
Herpes simplex encephalitis
commonest viral encephalitis
What is the normal nerve speed of a motor nerve?
> 49m/s
if <49m/s = problem with the myelin sheath around the nerve
What are the key features in the initial presentation of Acute Cervical Cord Syndrome? (5)
- Mixture of 4 limb motor + sensory weakness
- Sphincteric syndromes (bladder urgency/frequency)
- Pain
- Increased tone + reflexes (although in very acute setting = flaccid + absent reflexes = ‘spinal shock’)
- May just involve posterior cord = no motor signs = sensory ataxia
What are the key features in the initial presentation of Cauda Equina Syndrome? (6)
- Lower limb symptoms + signs, with normal upper limbs
- Combo of motor + sensory problems
- Bladder disturbance
- Saddle anaesthesia
- Pain
- Examination will reveal LMN signs only!
What are the key features in the initial presentation of Myasthenia Gravis? (4)
- Muscle weakness (no sensory problems)
- Typically include eyes, mouth, proximal limbs
- Respiratory muscles may be involved = breathlessness when lying down b/c of weak diaphragm
- Weakness is fatiguable (i.e. worse late in day, after exercise)
What are the key features in the initial presentation of Acute Myositis? (3)
- Proximal limb muscle weakness
- Pain
- Normal reflexes + sensation
A 25 year old man presents to A+E with a 3 day history of weakness and numbness affecting the hands and feet. He has no change in vision, speech or swallowing. He has noticed some increasing urinary frequency and urgency.
What is the most likely anatomic site affected by pathology?
Cervical spine
- He has 4 limb symptoms + urinary disturbance
A 25 year old man presents to A+E with a 3 day history of weakness and numbness affecting the hands and feet. He has no change in vision, speech or swallowing. On examination he is alert and has normal cranial nerves. Limb exam reveals normal tone, weakness, absent reflexes and reduced sensation distally.
What is the most likely cause for these problems?
Acute polyneuropathy
- Would account for the rapid onset of 4 limb symptoms + LMN signs on exam
A patient with rapid onset weakness affecting all 4 limbs undergoes a lumbar puncture. The following results are available:
- Opening pressure 17cm
- WBC 4
- RBC <1
- Protein 0.9g/L
- Glucose 3.6 mmol/L (serum 6.0 mmol/L)
Which diagnosis these results support?
Guillian-Barré Syndrome
- Cytoalbuminologic dissociation (high protein count) is seen here
A 72 year old lady has been complaining of intermittent diplopia to her GP. Whilst waiting for an appointment with the ophthalmologists she develops problems in swallowing and difficulty rising from a chair unaided. When admitted to hospital she is found to have bilateral ptosis and facial weakness. She is dysarthric. She has normal tone and reflexes in the limbs but proximal weakness that gets worse during the course of the assessment.
What’s the most likely diagnosis?
Myasthenia Gravis
A 25 year old man presents to A+E with a 3 day history of weakness and numbness affecting the legs and feet. Examination reveals normal cranial nerves and upper limbs. In the lower limbs there is increased tone, brisk reflexes, upgoing plantars and grade 4 power in all muscle groups tested. Sensation to pinprick is altered throughout the legs and pelvic area. Joint position sense seems intact.
What’s the most useful diagnostic test?
MRI thoracic spine
- MRI thoracic spine is most likely to reveal the underlying cause as the symptoms and signs are compatible with a thoracic myelopathy.
What are possible treatments for Bell’s palsy? (2)
- Steroids (prednisolone)
2. Aciclovir (weak evidence)
How long does it take for Bell’s palsy to resolve?
4-6 months (recurrence is uncommon)
What are possible causes of Bell’s palsy? (2)
- Inflammation
2. Viral infection
What is Ramsay Hunt syndrome? (4)
- Herpes zoster (“shingles”) of the geniculate ganglion of the facial nerve
- Associated with painful vesicles affecting the external ear and occasionally on the palate
- Treated with acyclovir + high-dose steroids
- Important differential for Bell’s palsy
In what settings is a Left Common Peroneal Nerve Palsy common? (1)
- Prolonged/repeated knee flexion (i.e. kneeling)
What movements is the common perineal nerve responsible for? (2)
- Ankle dorsiflexion (innervates tibialis anterior)
2. Foot eversion (innervates peroneal muscles)
What muscle and nerve are responsible for foot inversion? (2)
- Tibialis posterior
2. Tibial nerve
When there is weakness of ankle inversion and eversion, + loss of ankle reflex what is the likely diagnosis? (1)
- Prolapsed (‘slipped’) intervertebral disc causing compression of the L5 and S1 nerve roots
What investigations are useful to confirm the diagnosis of foot drop? (3)
- Nerve conduction studies
- Ultrasound
- MRI/CT
What is the treatment for foot drop? (1)
- Footdrop splint (ankle foot orthosis)
How long will a foot drop take to heal depending on the cause of injury? (2)
- Demyelination lesions = full recovery within weeks
2. Axonal loss = longer, and likely incomplete recovery
What is the typical presentation of a radial nerve palsy?
Wrist drop
- Typically due to the compression of the radial nerve against the mid-shaft of the humerus
- Neurophysiology can be helpful to confirm diagnosis
- Wrist drop splint used for treatment
What features on a neurophysiological study would indicate there’s a conduction block? (2)
- Poorly formed waveform
2. Lower amplitude of the waveform
What is the recommended treatment for Bell’s palsy? (1)
Oral prednisolone 60mg for 1 week
In UMN facial weakness, what can be observed on examination? (1)
Sparing of the forehead
What are the 3 features of Ramsay Hunt syndrome?
- Pain
- Vesicular rash
- Facial palsy
A 55 year old man with a history of chronic back pain presents with 2 weeks of worsening back pain. This morning he noticed he was tripping on his right foot. On examination the cranial nerves and upper limbs are normal. In the lower limbs there is normal tone but weakness of right foot dorsiflexion. Reflexes are present at the knee but absent at both ankles. There is reduced pin prick sensation on the lateral border of the right shin.
What’s the likely diagnosis?
L5/S1 radiculopathy
What are 3 triggers for seizures?
- Severe illness
- Dehydration
- Overtiredness
What are 5 features that typically occur during an epileptic seizure?
- Pain
- Injuries
- Tongue biting
- Fecal/urinary incontinence (urinary incontinence also common in vasovagal syncope, esp in women)
- Cyanosis of the lips
What happens to the jerking movements during a generalized tonic-clonic seizure? (1)
They reduce in amplitude and frequency during the attack
What is the typical duration of a generalized tonic-clonic seizure?
5min
If longer = status epilepticus or non-epileptic attack disorder
In what condition is prolonged unresponsiveness/’pseudo sleep’ seen? (1)
Non-epileptic attack disorder (NEAD)
Name 2 metabolic disturbances that can give rise to seizures?
- Hyponatremia
2. Hypocalcemia
What investigations should be ordered for someone with a transient loss of consciousness? (6)
- Vital signs
- Blood glucose
- ECG
- Neurological examination
- Bloods (U&Es)
- CT head
What is a simple partial seizure? (2)
- Uncontrollable twitching of which the patient is fully aware
- May be able to communicate normally throughout the event
What is a complex partial seizure? (2)
- Abnormal uncoordinated electrical discharges are confined to one area of the brain
- Awareness is impaired during the event (even though the patient may not lose consciousness completely + may partially remember the events afterwards)
What are the symptoms of a temporal lobe seizure? (6)
- Memory disturbances (i.e. deja vu)
- Olfactory + auditory hallucinations
- Epigastric sensations
- Fear
- Bizarre psychic phenomena (i.e. derealisation, depersonalization, attacks of elation)
- Automatisms (i.e. lip-smacking, repetitive mumbling)
What are possible risk factors for developing epilepsy? (8)
- Birth history (prematurity, difficult delivery - forceps, postnatal difficulties - hypoxia, jaundice)
- Childhood milestones/developmental delays
- Seizures in childhood/infancy
- Significant head injuries
- History of CNS infections (meningitis, encephalitis, abscess)
- Family history of epilepsy
- Medications (some lower seizure threshold)
- Recreational drugs/alcohol
What is a prolonged febrile convulsion? (3)
- Typically occur around 18mo
- Associated with high fever
- Risk factor for developing epilepsy in later life (originating in temporal lobes)
What changes are evident in epilepsy due to previous prolonged febrile convulsions in the temporal lobes on MRI? (2)
- Atrophy
- Scarring (glosis) = high signal on MRI
= Mesial Temporal Sclerosis (MTS)
Which anticonvulsant drug requires close monitoring with blood tests?
Phenytoin b/c there’s a close correlation between serum level + efficacy
What are the 3 features of fetal valproate syndrome?
- Dysmorphia
- Developmental delay
- Cognitive impairment
What are the possible complications associated with sodium valproate use? (2)
- Major congenital defects (spina bifida, anencephaly)
2. Fetal valproate syndrome
What are the 4 issues of switching anticonvulsant medications?
- Avoiding breakthrough seizures (titrate down old drug)
- Tolerability of new drug (possible side effects)
- Potential drug interactions (esp OCP)
- Implications for driving (DVLA must be informed + withhold license for at least 6mo)
When changing anticonvulsant drugs, what are the implications for driving? (2)
- Must stop driving for at least 6mo + inform the DVLA
2. DVLA recommend stop driving for the changeover period + 6mo afterwards (not legally enforced)
What are the 4 common side effects of lamotrigine?
- Sedation
- Dizziness
- Nausea
- Insomnia
What are 2 serious side effects of lamotrigine?
- Allergic skin rash
- Severe multi-system hypersensitivity reaction with fever + multi-organ failure (Steven-Johnson’s Syndrome)
**Interaction with sodium valproate can lead to #2!
What precautions must be taken for a women on anticonvulsants wishing to get pregnant? (3)
- Lowest possible dose of anticonvulsant
- Avoid unplanned pregnancy
- Take prophylactic folic acid 5mg/day as soon as contraception is stopped and through the 1st trimester
What factors can reduce seizure threshold? (8)
- Intercurrent illness
- Missing medication
- New medication that interacts with anticonvulsants (i.e. tramadol, amitryptiline)
- Alcohol excess
- Recreational drug use
- Metabolic disturbances (hyponatremia, hypoglycaemia)
- Insomnia, fatigue, jetlag
- GI disturbances (impair anticonvulsant absorption)
What are the driving implications after having a seizure?
Must inform the DVLA + license is withheld until the patient has been seizure-free for 1 year
What are the possible treatments for medically refractory epilepsy? (2)
- Try different anticonvulsants (polypharmacy with 2+ AEDs may work)
- Epilepsy surgery (if a well-defined structure in the brain is responsible for the seizures that could be resected without neurological deficit)
What is the treatment pathway for status epilepticus? (3)
- Benzodiazepine (IV lorazepam/diazepam; buccal/IM midazolam) -> if fitting for > 5min
- IV antiepileptic agent (Sodium Valproate/Phenytoin) -> if no response to step 1 within 10min
- General anaesthesia (Propofol) -> no response to step 2 within 30min
What general medical measures must be done when treating an epileptic patient? (10)
- Secure airway + resuscitate
- Administer oxygen
- Assess cardiorespiratory function
- Establish IV access (2 large bore cannulas)
- Measure blood glucose + correct immediately
- Check temperature
- Check blood gases
- If poor nutrition/alcoholism give Pabrinex/Thiamine
- If woman of childbearing age, consider pregnancy test
- Bloods (FBC, U+E, Glucose, Ca2+, Mg2+, CK, LFTs + INR, anti-epileptic drug level, alcohol/toxicology screen, culture if appropriate)
What is a good first line antiepileptic drug for someone on Warfarin?
Levetiracetam (doesn’t interact with warfarin)
A 45 year old patient presents to hospital having had a first ever attack of loss of consciousness and limb shaking. They have recovered well and should be able to go home the same day.
What is the most important investigation to perform before discharge? (1)
ECG
Where is the lesion to cause loss of vision in one eye? (3)
Anterior to the optic chasm:
- Optic nerve
- Retina
- Eye itself
What is an relative afferent pupillary defect and how is it explained by the neuroanatomy of the pupillary light reflex? (2)
- In normal circumstances the pupil remains constricted because of equal direct (light shone into that eye) or indirect (light shone into the other eye) stimulation.
- In an eye affected by optic neuropathy the pupil paradoxically dilates when light is shone into that eye as the direct stimulus (light via ipsilateral damaged optic nerve) is weaker than the indirect stimulus (light via intact contralateral optic nerve)
Where is the lesion that causes RAPD? (1)
Damaged cranial nerve 2 (optic neuropathy)
What conditions can lead to RAPD? (2)
- Optic neuritis
2. Multiple sclerosis (retrobulbar optic neuritis) -> recovery in 3-4 weeks
What is the pathophysiology of retrobulbar optic neuritis? (1)
- Autoimmune attack on the optic nerve
What systemic conditions may result in optic neuritis? (4)
- Vitamin B12 deficiency
- Systemic multisystem inflammatory conditions (i.e. SLE, GPA, EGPA, Antiphospholipid Syndrome, Sarcoidosis)
- Infectious triggers (HIV, Syphilis, Hepatitis B/C) -> rare
- Rare conditions (Neuromyelitis optica, Devic’s disease)
What blood tests would you order for someone diagnosed with optic neuritis? (5)
- Serum B12 levels
- Nonspecific markers of inflammation (ESR/CRP, serum electrophoresis)
- Immunological tests (ANA, ANCA, ds-DNA, ENA, anticardiolipin antibodies, serum ACE levels)
- Serology for infections (HIV, syphilis, Hep B, Hep C)
- Specific antibodies for rare conditions (aquaporin 4 antibodies)
What result on MRI would be indicative of optic neuropathy due to multiple sclerosis? (2)
- Swelling + high signal within the optic nerve
2. High signal lesions within the periventricular white matter (radiologically consistent with demyelination)
What is the typical orientation of a demyelination lesion on MRI (i.e. multiple sclerosis)? (1)
Perpendicularly orientated with long axis of the lateral ventricles
What areas of the brain could be responsible for gait ataxia? (4)
- Cerebellum + its connections (cerebellar ataxia)
- Dorsal columns of spinal cord (sensory ataxia)
- Peripheral nerves/nerve roots (sensory ataxia)
- Vestibular apparatus + connections
What is L’Hermitte’s Phenomenon? (2)
- Tingling sensations upon flexion + extension of the neck that radiates down spine
- Common sign in multiple sclerosis
Where are the most important locations for a multiple sclerosis lesion? (4)
- Corpus Callosum
- Juxta-cortical
- Brainstem (including cerebellum)
- Spinal cord
When can a diagnosis of Multiple Sclerosis be made? (1)
- 2 separate clinical attacks of inflammation within the CNS at different times and in different places
How is a multiple sclerosis relapse treated? (1)
High dose steroids
What are the potential risks of giving high dose steroids? (7)
- GI upset (use PPI cover)
- Agitation
- Restlessness
- Insomnia
- Frank behavioural disturbance (steroid psychosis)
- Hyperglycemia
- Avascular necrosis of hip (rare)
What is the first-line treatment of relapse in multiple sclerosis? (2)
- Methylprednisolone (PO, 500mg once daily for 5 days) - outpatient!
- Methylprednisolone (IV, 1g once daily for 3 days) - hospital admission required!
What is the criteria for being eligible for multiple sclerosis ‘disease-modifying treatment’? (1)
Patients experiencing 2+ significant relapses over a 2-year period
What blood test is very important in a patient presenting with a dorsal cord syndrome? (1)
Serum B12 levels
What (blood) tests are done before giving high dose steroids? (5)
- Symptoms of infection
- FBC
- Renal function
- Random glucose
- Urine dipstick (looking for signs of UTI)
What can an injection of Gadolinium contrast material on CT head indicate?
Areas of blood-brain barrier breakdown due to active/recent inflammation
Name a disease-modifying drug used in multiple sclerosis?
Betaferon (beta-interferon 1b)
Name 4 commonly used drugs to aid in symptomatic treatment of complications of multiple sclerosis
- Baclofen (for spasticity/increased tone)
- Gabapentin (for neuropathic pain)
- Sertraline (for depression)
- Oxybutinin (anticholinergic drug for neuropathic bladder)
What are the possible treatments for neuropathic pain? (5)
- Anticonvulsants (pregabalin, gabapentin)
- Tricyclic antidepressants (amitryptiline, nortriptyline)
- Carbamazapine, oxcarbazepine (if neuropathic pain of face related to trigeminal nerve)
- Selective serotonin + norepinephrine re-uptake inhibitors (duloxetine)
- Others (Capsaicin cream, Lidocaine patches, nerve blocks, epidural injections, surgical options)
What is multiple sclerosis?
Chronic autoimmune disease of the central nervous system (brain + spinal cord) causing demyelination
How does multiple sclerosis manifest?
- Optic neuritis (pain on eye movement, blurring vision, red colour saturation)
- Cerebral (fatigue, weakness, sensory disturbances)
- Brainstem symptoms (vertigo, slurred speech, incoordination, double vision)
- Spinal cord (weakness, sensory disturbance, autonomic dysfunction)
What are the different types of multiple sclerosis? (4)
- Relapsing-Remitting MS (most common)
- Secondary Progressive MS (initially relapsing followed by progressive disease with/without relapses)
- Primary Progressive MS (progression from onset. no attacks)
- Progressive-Relapsing MS (progression from onset with attacks)
What are the 3 types of multiple sclerosis lesions?
- Acute active plaques (in relapsing-remitting MS)
- Chronic active plaques (more in progressive MS)
- Chronic inactive plaques (in progressive MS)
What investigations are performed for multiple sclerosis? (3)
- MRI head
- CSF analysis
- Evoked potentials (how fast signals reach occipital cortex/dorsal columns)
What are the CSF results for a patient with multiple sclerosis? (4)
- Low WCC (<50 x 10^6/ml)
- Low protein (<1g/ml)
- High CSF/serum glucose ratio (>0.4)
- Oligoclonal bands present in CSF (absent in serum)
What is the pathophysiological meaning of oligoclonal bands being present in the CSF?
A production of immunoglobulins in the CNS meaning its a primary CNS disease (multiple sclerosis)
What are 4 examples of injectable disease-modifying treatments for multiple sclerosis?
- Beta interferon (IM/SC)
- Glatiramer acetate (SC)
- Alemtuzumab (IV)
- Natalizumab (IV)
What are 3 examples of oral disease-modifying treatments for multiple sclerosis?
- Dimethyl fumerate
- Teriflunomide
- Fingolimod
What is the mechanism of action of high dose steroids in treating a multiple sclerosis relapse? (2)
- Reduces inflammatory activity
2. Stabilizes the BBB
What is the mechanism of action of interferons used in multiple sclerosis? (1)
Interferes with T cell migration across the BBB
What is the mechanism of action of Teriflunomide in the treatment of multiple sclerosis? (1)
Anti-proliferative action
What is the mechanism of action of Glatiramer in the treatment of multiple sclerosis? (1)
Desensitising the immune system from myelin
What is the mechanism of action of Dimethyl Fumerate in the treatment of multiple sclerosis? (1)
Proinflammatory cytokine inhibitor
What is the mechanism of action of Fingolimod in the treatment of multiple sclerosis? (1)
Inhibits the migration of T cells from lymphoid tissue into blood by blocking S1P receptors
What is the mechanism of action of Alemtuzumab in the treatment of multiple sclerosis? (1)
Monoclonal targets B and T cells resulting in cell lysis
What is the mechanism of action of Natalizumab in the treatment of multiple sclerosis? (1)
Prevents lymphocyte migration across the BBB
What complications are associated with Alemtuzumab use (in multiple sclerosis)? (4)
- Antibody mediated autoimmune diseases
- Thyroid disease
- Immune thrombocytopenia
- Goodpasture syndrome
What complications are associated with Natalizumab use (in multiple sclerosis)? (1)
- Progressive multifocal leukoencephalopathy
- Caused by JC virus (John Cunningham virus)
What is a common MS relapsing symptom? (1)
- Urinary symptoms: frequency, urgency, retention
What is Devic’s syndrome (neuromyelitis optica)? (3)
- Inflammatory disease of the CNS
- Longitudinally extensive transverse myelitis (inflammation spanning more than 3 vertebrae)
- Optic neuritis
- NMO antibodies or aquaporin 4 antibodies present
Name 3 conditions that present like multiple sclerosis except they have more systemic symptoms
- Anticardiolipin antibody syndrome
- Neurosarcoidosis
- Sjogren’s syndrome
What structure is responsible for coloured vision + fine detail? (1)
Fovea
What structure is responsible for central visual acuity? (1)
Macula
When assessing the optic disc, what should you comment on? (3)
“3 Cs”
- Cup (cup to disc ratio)
- Colour (i.e. “pink healthy colour”/pale = nerve death)
- Contour (i.e. blurred/well-defined)
What is a normal healthy cup to disc ratio? (1)
0.3
What are the ocular muscles? (6)
- Inferior oblique
- Superior oblique (CN4)
- Medial rectus
- Lateral rectus (CN6)
- Superior rectus
- Inferior rectus
What questions would you ask in an ophthalmology history pertaining to the presenting complaint? (6)
- Pain
- Loss of vision
- Trauma
- Discharge
- Redness
- Photophobia
What questions need to be asked in the past ophthalmic history portion of an ophthalmology history? (3)
- Previous surgery
- Short/long sighted
- Contact lenses
What are 3 common ophthalmologic conditions that run in the family?
- Glaucoma
- Dystrophy
- Blindness
List 3 drugs that can affect vision?
- Anti-TB
- Amiodarone
- Chloroquine
Name 4 medical conditions that can have ophthalmic manifestations?
- Diabetes
- Hypertension
- RA
- Sarcoid
What does it mean to have myopic vision? (5)
- Short-sighted
- Large globe
- Problems with distance
- Glasses minify images
- Risk of retinal detachment
- Concave lens
What does it mean to have hypermetropic vision? (5)
- Long-sighted
- Small globe
- Problems with near vision
- Glasses magnify
- Risk of acute glaucoma
- Convex lens
What does it mean to have 6/6 vision?
Normal vision. A patient can see at 6m away from the chart what we would expect them to see at that distance.
If a patient cannot read the Snellen Chart, what other ways are there to test visual acuity? (3)
- Count fingers
- Hand movements
- Light Perception (if none = No perception of light (NPL)
Name 2 ways to test visual acuity in babies
- Preferential looking
2. Kay picture cards
Name 5 ocular emergencies
- Giant cell arteritis -> life threatening
- Central retinal artery occlusion (CRAO) -> sudden loss of vision
- Orbital cellulitis -> life threatening
- Retinal detachment
- Acute angle closure glaucoma
What is the most concerning cause of a white pupil (leukocoria) in a child?
Retinoblastoma
What is the most common cause of glaucoma? (1)
Raised intraocular pressure
How is glaucoma monitored? (1)
Assessing visual fields
