Neuro ILAs Flashcards
What are the eye symptoms and signs in optic neuritis?
- Blurred and cloudy vision
- Discomfort on eye movement
- Worse with heat
Signs:
- Reduced direct and indirect response
- Decreased visual acuity in one eye
- Normal fundoscopy and eye movements
What is Marcus Gunn pupil?
A medical sign observed during the swinging-flashlight test whereupon the pupils constrict less (therefore appearing to dilate) when a bright light is swung from the unaffected eye to the affected eye
What is 6/6 for visual acuity?
It means you can see at 6 metres what you should see at 6 metres
What are the HELLP questions to ask for unilateral visual loss?
Headache associated? Do ESR in all cases >50 years for GCA
Eye movements hurt? Optic neuritis
Lights/ flashes preceding visual loss? Detached retina
Like a curtain descending? Amaurosis Fugax
Poorly controlled diabetes and vitreous haemorrhage
What are the vascular causes of unilateral visual loss?
Amaurosis fugax/ central retinal artery occlusion
Central retinal vein occlusion
Anterior Ischaemic Optic Neuropathy (ischaemia of posterior choroidal artery)
What are other causes of unilateral visual loss?
- Optic neuritis
- Retinal detachment (flashes/floaters)- Vitreous haemorrhage (associated with diabetic retinopathy, also see vitreous floaters)
- Acute angle closure glaucoma
What are the causes of anterior ischaemic optic neuropathy?
Arteritic- Giant Cell Arteritis
Non-arteritic- atherosclerosis
What are the symptoms of GCA?
New-onset headache, malaise, jaw claudication, scalp tenderness, neck pain
Unilateral visual loss
What is GCA associated with?
Polymyalgia rheumatica
What are the tests for GCA?
ESR and CRP
Temporal artery biopsy
What is the treatment for GCA?
Prednisolone 60mg/24 hours
What are the symptoms of optic neuritis?
Afferent pupillary defect Subacute loss of vision Colour vision is affected Eye movements hurt Exacerbated by heat or exercise Risk of developing MS
What are the causes of optic neuritis except MS?
Inflammation of optic nerve
Syphilis
Leber’s optic atrophy
DM
Vitamin deficiency
What is the treatment of optic neuritis?
High dose methylprednisolone for 72 hours
(1000mg/24 hours IV)
Then Pred 1mg/kg PO for 11 days
What is retinal vein occlusion?
Second most common cause of blindness from retinal vascular disease (Diabetic retinopathy is first)
Causes= arteriosclerosis, hypertension, diabetes, polycythaemia, glaucoma
Less sudden than central retinal vein occlusion
How does central retinal vein occlusion present?
Sudden onset painless blurred vision in one eye
Can see dilatation of branch veins, multiple retinal haemorrhages and cotton wool patches
What investigations would you do?
History and examination
VEP/MRI (optic neuritis)
Fluorescein angiography (CRVO)
Tonometry- intraocular pressure measure (glaucoma)
USS- vitreous haemorrhage/ retinal detatchment
How is MS diagnosed?
The presence of multiple CNS lesions, which cause symptoms that
- last longer than 24 hours
- are disseminated in space (clinically or on MRI)
- are disseminated in time (>1 month apart)
What are the typical features of MS?
Visual loss (Optic neuritis) Pyramidal weakness, spastic paraparesis Sensory disturbance Cerebellar symptoms (nystagmus / vertigo / tremor /ataxia / dysarthria) Bladder involvement / sexual dysfunction Lhermitte’s & Uhthoff’s phenomenon Fatigue Cognitive impairment
What are the signs in MS?
UMN signs: spastic paraparesis, brisk reflexes
Sensory signs
Cerebellar signs (eyes, gait, UL, speech)
Optic atrophy
Relative afferent pupillary defect
Internuclear opthalmoplegia (decreased adduction of ipsilateral eye, nystagmus on abduction of contralateral eye)
What are the investigations in MS?
MRI scan
LP-oligoclonal bands
Evoked potentials e.g. VEPs
What is the pathophysiology of MS?
-Inflammatory
-Focal loss of myelin, with relative preservation of axons.
Neurodegenerative
-Axonal loss may contribute to fixed and progressive deficits.
Give a differential diagnosis of blackouts?
Syncope
Epilepsy
Non-epileptic attacks
What is syncope?
Syncope is an abrupt and transient loss of consciousness associated with loss of postural tone that follows a sudden fall in cerebral perfusion.
What is neurogenic syncope?
Inappropriate activation of cardio-inhibitory and vasodepressor reflex leading to hypotension
What are the causes of neurogenic syncope?
Vasovagal syncope
Reflex syncope with specific precipitants
- Micturition syncope
- Cough syncope
Carotid sinus hypersensitivity
What are other causes of syncope?
- Orthostatic syncope (autonomic failure)- primary (multisystem atrophy)
- Secondary (diabetes, drugs)
Cardiac syncope
- Arrhythmias
- Valvular heart disease
What is a seizure?
Clinical manifestation of disordered electrical activity in the brain (paroxysmal discharge of cerebral neurones)