Pathology Flashcards
Which tumours can affect the ventricles and choroid plexus
Colloid cyst - often at interventricular foramen
Ependymomas - arise from ependymal cells
Choroid plexus tumours
What is hydrocephalus
Accumulation of CSF in the brain
Usually due to some sort of blockage in the system
Can cause the head to enlarge and increases pressure in brain
Treated with a shunt
List the different types of ventricular haemorrhage
Epidural hematoma, arterial bleed between skull and dura
Subdural hematoma, venous bleed between dura and arachnoid
Subarachnoid haemorrhage
What is idiopathic intracranial hypertension
Increase in CSF pressure but no imaging features of hydrocephalus
No known cause
Causes headache and visual disturbance
What is papilloedema
Optic disc swelling due to raised intracranial pressure - puts pressure on the optic nerve
Causes enlarged blind spot, blurred vision and loss of vision
Graded from 1-5
What can cause raised intracranial pressure
Head injury
Space occupying lesion, tumour, abscess or haemorrhage
Hydrocephalus
Meningitis - leads to inflammation
What occurs if raised ICP is not relieved
Brain damage
What visual changes can occur with raised ICP
Transient blurry vision Double vision - diplopia Loss of vision Papilloedema Pupillary changes
Can affect one or both eyes depending on cause
How can raised ICP affect the optic nerve
Compresses them
Will also compress the blood supply to the retina
Leading to swelling off the optic disc - papilloedema
What visual symptoms occur with papilloedema
Transient visual obscurations Transient flickering Blurring Constriction of the visual field Decreased colour perception
Describe the appearance of the optic disc in papilloedema grade 1-5
Blurry margins in all grades 1 - C shaped halo 2 - circular halo 3 - peripheral vessels disappear from view 4 - central vessels disappear 5- no visible vessels
What can damage the oculomotor nerve
Compression by raised ICP
Tentorial herniation - pushed through notch by raised ICP
Which fibres tend to be affected first when the oculomotor nerve is compressed
Parasympathetic
They usually sit on the outside of the nerve
List symptoms of oculomotor nerve damage
Paralysis of extra-ocular muscles
No/slow pupillary reflex (parasympathetic not working)
Dilated pupil - when it becomes fixed it means there has been severe damaged
Ptosis - damage of nerve to LPS
Eye looking down and out - superior oblique still works
Describe symptoms of trochlear nerve damage
Paralysis of superior oblique muscle - cannot move inferomedially
Diplopia when looking down
What is diplopia
Double vision
What can damage the trochlear nerve
Stretching
Compression - ICP
isolated injury is very unusual
What type of damage is the abducent nerve susceptible to
Stretch
What are the symptoms of abducent nerve damage
Eye can’t move laterally in horizontal plane - lateral rectus is paralysed
Medial deviation of eye
What are cataracts
Opacification within the lens
Leads to reduction in vision which affects daily living
What can cause cataracts
Degenerative changes in lens fibres - age (most common)
Cumulative UVB damage
May also be caused by hypertension, smoking
Trauma - can be a sudden cataract
Metabolic - diabetes
Congenital
Drug induced - steroids
Intra-uterine infections - rubella, CMV, toxoplasmosis
What is glaucoma
A group of diseases characterised by progressive optic nerve damage and visual field loss
Abnormal increase in pressure in the eye
Due to the amount of vitreous fluid and aqueous humour
What areas of the eye does glaucoma have the biggest consequences
Optic disc and nerve
What causes 50% of blindness worldwide
Cataracts
rarely causes blindness in UK but is the most common cause of gradual visual impairment,
What are the two types of glaucoma
Open angled - primary and secondary
Angle closure - primary or secondary
What causes open angled glaucoma
Poor drainage through the trabecular network
Fluid builds up
Primary - nothing to see in eye
Secondary - there is something else is blocking the drains – red cells, white cells in uveitis, protein etc.
How does open angled glaucoma present
Very slow onset
Usually asymptomatic - picked up by screening
Will see an open anterior chamber angle, raised intra-ocular pressure, “cupping” of the optic disc and progressive loss of visual fields
How do you treat primary open angled glaucoma
Pharmacological treatment - prostaglandin then B-blocker or CAI then truspot/alphagan
Then surgery - trabeculectomy
Make a fistula in the eye to allow drainage
What causes angle closure glaucoma
Iris becomes opposed to the lens and stops fluid flowing round to the trabecular network
Drainage is patent but fluid cannot get to it
The iris can close over the angle
Fluid builds up and increases pressure
How does angle closure glaucoma present
Unilateral Visual loss Pain Red eye Cloudy / Hazy cornea Fixed, mid dilated pupil Severe headache May have nausea and vomiting Raised intra-ocular pressure (50-80mmHg)
Can be a medical emergency
How do you treat angle closure glaucoma
Laser treatment to the iris - iridotomy
Zap a hole to allow fluid to drain - reduces recurrence
Can also give IV Diamox – carbonic anhydrase inhibitor, topical anti-hypertensives, topical steroids, pilocarpine
What is ‘cupping’ of the optic disc
Edges of the optic disc become rolled up and the centre depressed
Caused by pressure damage
Which cancers can affect the eye
BCC
SCC
Melanoma
Which part of the body is the only one with no reported incidence of malignancy
lens
What is conjunctivitis and how does it present
Inflammation of the conjunctiva
Caused swelling, redness, pain and heat
Usually viral
What is scleritis and how does it present
Inflammation of the sclera
rarer and more severe
Associated with pain on movement and deep redness
Episcleritis is usually self-limiting - true or false
True
It’s a superficial inflammation
What is ARMD
Age related macular degeneration
What are the 2 types of macular degeneration
Dry - no vascular proliferation
- more common
Wet - vascular proliferation
- eye grows new blood vessels within the macula to ‘repair’ dry ARMD damage but they leak
How do you treat wet macular degeneration
Anti-VEGF monoclonal antibodies
Injected into the eye
Stops proliferation of blood vessels
What is Drusen
Accumulation of dry product of inflammation (e.g. proteins, lipid etc)
Appear as little yellow plaques on retina
What is an Argyll Robertson pupil
Accommodates but doesn’t react
Doesn’t constrict/dilate but you can see near and far
What eye pathologies can be caused by diabetes
Blurred vision - increased osmotic pressure Peripheral neuropathy can affect eyes Cataracts Rubeotic glaucoma Retinopathy
How does diabetes cause cataracts
Increased sugar in lens, converted to sorbitol which gets stuck in the cells
Alters the osmotic gradients and leads to swelling and fibre disruption
What is retinopathy
Poor functioning of vessels in the eye
Leaky and haemorrhages
Leads to vision loss
What vascular diseases can affect the eye
Arterial occlusion -thromboembolic disease in carotids
Venous - giant cell arteritis (temporal)
What happens if you have a TIA in the central artery of the eye
Sudden visual loss in one eye - like a curtain coming down
Not painful
What is the cardinal feature of an eye movement defect
Double vision (diplopia)
What is the cardinal feature of a visual defect
Loss of visual acuity
Loss of visual fields
List potential causes of eye disease
Vascular disease Tumours - SOL Trauma Demyelination - MS Inflammation/infection Congenital abnormalities
What does a VIth nerve palsy lead to
Palsy of the lateral rectus
Will no longer be able to abduct the eye
Causes horizontal double vision
What can cause a VIth nerve palsy
Microvascular
Raised Intracranial pressure
Tumour - acoustic neuroma
Congenital
Why is the VIth nerve susceptible to damage by raised ICP
The course of the nerve
It runs over a tip in the bone and is easily compressed
What does a IVth nerve palsy lead
Palsy of the superior oblique muscle
Eye will sit higher and outwards
Cannot move the eye down and in
Get vertical double vision
How might people compensate for a IVth nerve palsy
Tilting their head
What can cause a IVth nerve palsy
Congenital defect
Microvascular complication
Tumour
If bilateral it is usually trauma
How does the eye appear in a IIIrd nerve palsy
Eye will sit down and out
Dilated pupil
Drooping eyelid
Affects MR, SR, IR, IO, sphincter papillae and LPS
What can cause a IIIrd nerve palsy
Microvascular problems Tumour Aneurysm (will be painful!) - 3rd nerve passes very close the PCA so aneurysm in this can compress the nerve MS Congenital
What causes inter-nuclear ophthalmoplegia
MS
Vascular issues
etc etc
What is the inter-nuclear pathway involves in
Allows the eyes to work together
SO they look the same way, at the same time, at the same speed
What pathologies commonly cause defects in the optic nerve
Ischaemic optic neuropathy
Optic neuritis - common in MS
Tumours - rare
How does an optic nerve defect affect the visual fields
Either complete loss of vision unilaterally or loss of horizontal field in one eye
How does optic neuritis present
Progressive, unilateral vision loss Pain behind the eye, especially on movement Colour desaturation Central scotoma Enlarging blind spot RAPD Optic disc swelling
Which pathologies can affect the optic chiasm
Pituitary tumour
Craniopharyngioma
Meningioma
Defect in the optic chiasm leads to what visual defect
Bitemporal hemianopia
What pathologies can cause defects in the optic tracts and their radiations
Tumours
Demyelination
Vascular anomalies
How does a defect in the optic tracts and their radiations present
Homonymous defect - affects the same side of each eye
Macula is not spared
Affects in quadrants or as hemianopia (halves)
What pathologies can cause defects in the occipital cortex
Vascular disease
Demyelination - MS
How do defects in the occipital cortex present
Homonymous defect - affects same side of both eyes
Macular sparing
List causes of sudden visual loss
Vascular occlusion - central retinal artery or vein Ischaemic optic neuropathy Vitreous haemorrhage Amaurosis Fugax Retinal detachment Retrobulbar neuritis ARMD - wet type Closed angle glaucoma Optic neuritis Giant Cell Arteritis Cerebral infarct involving the optic tract or occipital cortex
Haemorrhage from abnormal blood vessles occurs in which eye pathologies
Diabetic retinopathy
Wet ARMD
What are the signs and symptoms of a central retinal artery occlusion
Sudden visual loss - total or subtotal No pain RAPD Pale retina Pink spot at fovea as still has some blood supply from choroid - cherry red spot
What can cause a central retinal artery occlusion
Carotid artery disease
Emboli from the heart
- may see common CV risk factors
GCA
What can cause a central retinal vein occlusion
Endothelial damage - diabetes
Abnormal blood flow - hypertension
Hypercoagulable states - cancer
What are the signs and symptoms of a central retinal vein occlusion
Sudden vision loss - mod to severe Painless RAPD Retinal haemorrhages - flame shaped, stormy sunset Cotton wool spots Dilated, tortuous veins Disc swelling
What is ischaemic optic neuropathy
Occlusion of the circulation to the optic nerve head
Can be caused by giant cell arteritis (inflammation occludes the vessels) or atherosclerosis (usual risk factors)
Leads to sudden, severe visual loss - irreversible
RAPD
Swollen optic disc with hyperaemia. Pale disc later
List symptoms of giant cell arteritis
Headache - temporal Jaw/tongue claudication Scalp tenderness Tender and enlarged scalp arteries Malaise Shoulder girdle weakness Recent weight loss Sudden visual loss - if progresses to ION May also have blurred vision, amaurosis fugax and diplopia
What are the symptoms of a vitreous haemorrhage
Sudden loss of vision
Floaters in vision
Loss of the red relflex
May see the haemorrhage on fundoscopy
What are the signs and symptoms of retinal detachment
Painless vision loss Sudden onset of flashes/floaters Dark shadow in peripheral vision, increasing in size May have RAPD May see the tear with ophthalmoscope
Sudden visual loss occurs with dry ARMD - true or false
False
It occurs with wet ARMD
Dry leads to progressive loss
What are the signs and symptoms of wet ARMD
Rapid central visual loss Distortion - straight lines bend (metamorphopsia) Haemorrhage and exudate on imaging Oedema over macula - slightly paler Fluid build up on OCT
What are the signs and symptoms of closed angle glaucoma
Painful, red eye Sudden visual loss Headache Nausea and vomiting Cloudy cornea Circumcorneal injection Dilated pupil
List causes of gradual visual loss
Cataract Dry ARMD Refractive error Glaucoma - open angle Diabetic retinopathy Age related changes
What are the symptoms of cataracts
Gradual visual decline - haziness/blurriness
May get a glare
How do you treat cataracts
Surgical removal of the lens - phacoemulsification
Replace with an intra-ocular lens implant
What are the signs and symptoms of dry ARMD
Gradual visual decline - blurriness
Central vision missing - central scotoma
Drusen - build up of exudate seen as yellow deposits around macula
May also see abnormal pigmentation in this area
Atrophic parts of retina on imaging
What is a refractive error
Eye cannot clearly focus images
Includes being short or long sighted and stigmatism
What are the signs and symptoms of open angled glaucoma
Often asymptomatic - picked up by optician
Cupped disc
Visual field defects
High IOP
How does raised ICP lead to papilloedema
Optic nerve is also surrounded by meninges and therefore CSF
So an increase in pressure in the SAS around the optic nerve affects it
What is the major complication of raised ICP
Brain ischaemia and swelling
Brain gets pushed through the foramen magnum which compresses the brain stem and the patient will stop breathing
Malignant hypertension can lead to papilloedema - true or false
True
What leads to accumulation of CSF
Obstruction to it’s circulation
Overproduction
Inadequate absorption
What is idiopathic intercranial hypertension
Cause of papilloedema
May be a result of stenosis of cerebral sinuses, increased abdominal pressure (obesity), microemboli
Poorly understood
What can happen if disc swelling becomes chronic
They become atrophic and pale
There may be a loss of visual function and even blindness
What signs might you see in retinopathy
Microaneurysms - dot and blot haemorrhages
Hard exudate
Cotton wool patches
Abnormal blood vessels
Venous beading – segmentation of the veins
IRMA – shunt vessels between the arterioles and venules formed by the ischaemic drive, normal vessels, not very leaky
What drives new vessel formation
VEGF
What is the difference between NVD and NVE
NVD - new vessels on disc
- worse prognosis
- suggests severe ischaemia
NVE - new vessels in periphery
- occurs locally to the ischaemia
What is rubeosis iridis
Vessel formation on the iris
Due to extreme VEGF production due to severe ischaemia
Irreversible
Very poor prognostic sign – suggests severe ischaemia
Why can diabetic patients lose vision
Retinal oedema
Vitreous haemorrhage
Scarring and tractional retinal detachment
How do you manage diabetic eye disease
Optimise control Laser treatment - photocoagulation to stop bleeds Vitrectomy - surgical Rehabilitation Anti-VEGF injections
List features of hypertensive retinopathy
Attenuated blood vessels Cotton wool spots Hard exudate Retinal haemorrhage Optic disc oedema
How does an infarcted retina appear
Very Pale
What are keratic precipitates
Deposits of white cells in the eye
Appear as little white dots in the eye
List some infective causes of uveitis
TB
Herpes zoster
Syphilis
List some non-infective causes of uveitis
Idiopathic
Sarcoidosis
Ankylosing spondylitis
Juvenile arthritis
List features of thyroid eye disease
Proptosis Lid retraction and lag Lid oedema Restrictive myopathy Glaucoma Injection
How can SLE affect the eyes
Leads to red, inflamed eyes
Deep tissue involved - scleritis
How can RA affect the eyes
Dry eyes
Scleritis
Corneal melt
How does Marfan’s present in the eyes
Displacement of the lens
Will go up the way
\what can cause a subconjunctival haemorrhage
Can be spontaneous - particularly if on anti-coagulants
Trauma
Hypertension
What can lead to orbital cellulitis
Insect bite
Eye lid trauma
In kids it’s often caused by sinus infection that travels up to eye
What is the major consequence of orbital cellulitis
Brain abscesses - this can be life threatening
Who is vulnerable to acanthamoeba infections
Contact lens wearers
Describe how different types of pain suggest pathology in different parts of the eye
Grittiness - surface problem
Achy pain - intraocular
What is the difference between anterior and posterior blepharitis
Anterior - lid margin and lashes affected
- lid margin is redder than deep eye
Posterior - due to Meibomian gland dysfunction
- redness is in deep part of the lid
What are the Meibomian glands
oil secreting glands in the posterior part of the lid
if they don’t work properly it can lead to blepharitis
What are the symptoms of blepharitis
Similar to conjunctivitis
Gritty eyes - foreign body sensation
Mild discharge
What are the signs of seborrheic anterior blepharitis
Red lid margin
Lots of scales
No ulcers
Lashes stuck together
What are the signs of staphylococcal anterior blepharitis
Red lid margin
Lashes distorted - loss or ingrown
Styes
Marginal ulcers
What are the signs of posterior blepharitis
lid margin and lashes unaffected
Gland opening swollen
Dry secretions at gland openings
Meibomian cysts
What other condition is posterior blepharitis associated with
Acne rosacea
How do you treat blepharitis
Lid hygiene - daily bathing
Supplementary tear drops
Oral doxycycline for 2-3 months
List causes of conjunctivitis
Viral - watery, after URTI Bacterial - purulent, sticky Chlamydia - low grade and chronic Allergic Chemical/drugs Associated with skin disease
List symptoms of conjunctivitis
Red eye Foreign body sensation - gritty eyes Discharge - watery or purulent Pre-auricular lymph nodes - viral causes Chemosis Itch (in allergic) Papillae or follicles Vision unaffected
In herpes zoster infections, why would you be concerned if the nose was affected
If the tip of the nose is affected it means the nasocilliary nerve has been affected and so it is likely the eye will be involved
This is when shingles affects the V1 nerve
List signs and symptoms of corneal ulcers
Pain - needle like and severe Photophobia Profuse lacrimation - watery Red eye - around the cornea Corneal opacity Staining with fluorescein Hypopyon
How do autoimmune corneal ulcers occur
Common in RA
Indicates that the systemic autoimmune condition is poorly controlled
Aside from bacteria and viruses, what can cause corneal ulcers
Exposure keratitis - seen in those who cannot fully close their eyes (thyroid or nerve palsy)
Dry eyes - Sjorgen’s
Neurotrophic - herpes zoster
Vit A deficiency
How do you treat a corneal ulcer
Corneal scrape to identify cause
Antimicrobials if bacterial
Antiviral if herpetic - aciclovir for 7-`10 days
Anti-inflammatory if autoimmune
List causes of anterior uveitis
Idiopathic - 50-60%
Autoimmune - UC, sarcoid, ank spond (associated with HLA-B27)
Infective - TB, syphilis, herpes (uncommon)
Malignancy
Trauma
List signs and symptoms of anterior uveitis
Pain - dull ache May have reduced vision - blurry Photophobia Red eye - around cornea Ciliary injection Cells and flare in anterior chamber Precipitates Hypopyon Irregular pupil Posterior synechiae – pupil gets stuck down, may not dilate well
How do you manage anterior uveitis
Topical steroids - 4-8 weeks
Hourly with gradual taper
Mydriatics - paralyses the muscle and reduces photosensitivity and pain from spasm
Investigate systemic causes
Which other pathology is episcleritis associated with
Gout
How do you differentiate between episcleritis and scleritis
Adding a vasoconstrictor like topical phenylephrine – in episcleritis the redness would blanche, if deeper inflammation like scleritis it would not
How do you manage episcleritis
Usually self-limiting
Lubrication
Rarely a topical NSAID
Which other pathologies is scleritis associated with
RA
Wegener’s granulomatosis
Many connective tissue diseases
List symptoms of scleritis
VERY painful
Will wake you up from sleep and cannot touch the eye
Injections of the deep vascular plexus - diffuse and deep redness
How do you treat scleritis
Oral NSAIDs
Oral steroids
Steroid sparing agents
A droopy eyelid may be a sign of what extra-ocular pathology
Lung cancer
This is a sign of Horner’s syndrome (constricted pupil and reduced ipsilateral sweating)
What is RAPD and how would you diagnose it
Relevant afferent pupil defect
Do the swinging light test
You would see paradoxical dilation of one pupil when you shine the light in it
New vessels form in dry ARMD - true or false
False
This occurs in wet ARMD and can lead to visual loss
What are the signs of a macular pathology
Disturbance of central vision
Straight shapes and faces become distorted
How can you treat diabetic retinopathy
get diabetes under control
laser treatment - target the new vessels
anti-VEGF injections
In the UK, what vision level is considered partially sighted
6/60
In the UK, what vision level is considered severely visually impaired
3/60
What is emmetropia
normal vision
What is presbyopia
Loss of accommodation seen in old age
What is myopia
being short sighted
Eye is too large so focuses light before the retina
what is hypertropia
being long sighted
eye is small so focuses light behind the retina
List causes of a red eye
Infective Conjunctivitis Foreign Body Allergic Conjunctivitis Corneal Abrasion Blepharitis/ Chalazion Dry Eyes Subconjunctival Haemorrhage Glaucoma Anterior Uveitis
Pain and photophobia is characteristic of which condition
Anterior uveitis
Superficial dendritic ulcers are characteristic of what
Herpes simplex infection/ulcer
Sudden and painful loss of vision is suggestive of what
Acute angle closure glaucoma
What is amaurosis fugax
A transient loss of vision in one eye lasting usually
only a few minutes and at most a few hours - essentially a TIA involving the eye
What can cause amaurosis fugax
Usually secondary to embolic event from carotid or heart
Must be investigated as a TIA – risk of stroke is high
How do you treat wet ARMD
Anti-VEGF injections - injected straight into the vitreal body of the eye
This inhibits the growth factors stimulating new vessel growth
What are the risk factors for diabetic retinopathy
Increased duration of diabetes - 90% of type ones will have it after 20 years
Poor diabetic control
Active treatment is available for dry ARMD - true or false
False
Only available for wet ARMD in the form of anti-VEGF injections
Halo’s forming around lights is a sign of which eye condition
Associated with corneal oedema which is seen in acute angle closure glaucoma
Giant cell arteritis can lead to irreversible blindness - true or false
True
One of the true ophthalmic emergencies
Blindness can be bilateral and irreversible
How do you treat giant cell arteritis
High dose oral steroids which are tapered down over months
What type of discharge is seen in bacterial eye infections
Sticky and purulent
What type of discharge is seen in viral eye infections
Watery
Also seen in surface eye irritation such as foreign bodies
What type of eye pain indicates a surface issue
Scratchy / gritty / discomfort
E.g. conjunctivitis, foreign body
What type of eye pain indicates an intraocular issue
Severe / deep / aching pain
E.g. iritis, scleritis, angle closure glaucoma
What type of redness indicates an intraocular issue
Diffuse injection
If it is greatest around the cornea - circumcorneal
What is chemosis
Oedema of the conjunctiva Makes the eye look like jelly
Seen in conjunctivitis
How do you treat bacterial conjunctivitis
Treat with topical antibiotics ie chloramphenicol
How do you treat viral conjunctivitis
Supportive treatment
Cool compresses, lubricants etc.
What features are suggestive of chlamydia conjunctivitis
Young patient - sticky + red in first 10 days after birth
Unilateral
Follicular conjunctivitis
Diagnose by PCR swab
List risk factors for corneal ulcers
Corneal abrasion
Contact lens wearer
Dry eye
Iatrogenic -loose suture or surgery
If you apply topical steroids to a herpetic ulcer what can happen
It can lead to a geographic ulcer - the infection spreads across the eye
How do you treat chlamydial conjunctivitis in an infant
Swabs
Erythromycin
contact traces
How does a blocked nasolacrimal duct present in infancy
Sticky + white uninflamed eye from 2 months
Congenital block in the duct
How do you treat a blocked nasolacrimal duct
Bathe and massage sac
Most resolve spontaneously by 1 year
Syringe and probing if not resolving
What is the leading cause of blindness in people of working age in industrialized countries
diabetic retinopathy
List risk factors for developing diabetic retinopathy
Increasing duration of diabetes Poor blood sugar control Hypertension Dramatically* improved diabetic control - sudden increase in control leads to short term worsening of the retinopathy Hypercholesterolaemia Pregnancy
Describe the pathogenesis of diabetic retinopathy
Chronic hyperglycaemia
Glucose molecules attaches to the basement membrane of the vasculature of the retina
Causes a loss of pericytes
This leads to vascular dysfunction and increases permeability
Reduced O2 transport leads to tissue hypoxia
Vaso-formative factors produced - VEGF
New vessel formataion occurs to overcome the hypoxia
New vessels do more harm than good – they leak a lot
Get haemorrhage and scarring
What is the function of the pericytes in the eye
Pericytes help with the tight junctions in the eye vasculature – maintain eye/blood barrier
They are lost in diabetic retinopathy
How can diabetic retinopathy lead to retinal detachment
DR can cause scarring
Contraction of scarring in the vitreous can lead to retinal detachment
What causes visual loss in diabetic retinopathy
Retinal oedema affecting the fovea - macular oedema
Vitreous haemorrhage - due to leaking of the new vessels
Scarring/ tractional retinal detachment
How is diabetic retinopathy classified
By the grade of the retinopahty and the maculopathy
List the grades of retinopathy seen in diabetic retinopathy
None Mild - micro-aneurysms Moderate - microaneurysm, hard exudates, flame shaped haemorrhage Severe Proliferative - new vessles
How do you manage each grade of retinopathy
None-severe - observe and re-screen
If proliferative you give laser treatment
List the grades of maculopathy seen in diabetic retinopathy
No maculopathy
Observable maculopathy - exudates between 1 & 2 disc diameters of the centre of the fovea
Referable maculopathy - any blot haemorrhages or hard exudates – within 1 disc diameter
How can you treat the maculopathy seen in diabetic retinopathy
You treat if they have reduced vision
Intravitreal anti-VEGF injections are the gold standard now – better outcomes for preserving vision
Focal laser at macula – if they don’t respond to injection
Describe the pathogenesis of glaucoma
Usually blockage to aqueous outflow - obstruction to drainage
Causes raised intra-ocular pressure
Damage and loss of retinal nerve fibres at optic disc
Visual field loss
What is considered normal IOP
11.5-21.5 mmHG is considered normal
Why is peripheral vision lost first in glaucoma
In periphery lots of photoreceptor’s feed into the same ganglion cell, in the macula less photoreceptors per ganglion
Therefore, loss of ganglion cells in periphery is noticed first as it wipes out more photoreceptors
List risk factors for primary open angle glaucoma
Age raised intraocular pressure Afro-Carribean origin Family history Myopia – short sighted is a risk
Being highly myopic (very short sighted) increased the risk of which other condition
Retinal detachment - have larger eye so retina is thinner and vitreous is more watery so can move about more and separate more easily
Open angled-glaucoma
Being highly hypermetropic (very long sighted) increased the risk of which other condition
Acute angle closure glaucoma
What are the main subtypes of cataract
Nuclear Sclerotic – most common type, brown/green appearance
Cortical – spoke like pattern
Posterior Subcapsular - cataract develops at the back of the lens between the lens and the back of the capsule
Mature - appears white
A mature cataract has an increased operative risk - true or false
True
What is the most common cause of blindness in the elderly in the western world
ARMD
How do you manage dry ARMD
No active treatment, just prevent progression to wet ARMD
Low Visual Aids
Dietary / smoking advice
- Vitamin rich diet can reduce further visual loss and prevent progression to Wet ARMD
- Macula is very sensitive to smoking damage so promote cessation
Amsler Grid - allows patients to monitor visual distortion – one of the first signs of progression to wet is increased distortion of straight lines
Blind registration
What is OCT
Ocular Coherance Tomography
Cross sectional map of the retina
Can be used to diagnose and monitor wet ARMD
How do you treat a central retinal artery occlusion
Only effective if presentation within 12-24 hrs
Treatment aims at dislodging blockage and restoring circulation
Ocular massage - can change the pressure in the eye and force may dislodge the blockage
Paper bag breathing – increases PCO2 which causes reflex vasodilation and may allow the blockage to move
IV Diamox - CAI which drops the intraocular pressure so pressure behind blockage is greater than in front and may push it on
Anterior Chamber Paracentesis – remove some aqueous fluid to reduce IOP and again move blockage down vascular tree
What causes a cotton wool spot to appear in the retina
It is ischamia of the nerve fibre layer of retina
How do you treat a central retinal vein occlusion
If no signs of ischaemia - observe (every 3 months initially then less frequently)
If ischaemic but no neovascularition - observe closely (every 4-6 weeks )
If ischaemic with neovascularisation – requires urgent argon laser pan-retinal photocoagulation
also try and find underlying risk factors and modify them
How do you treat ischaemic optic anterior neuropathy
No active treatment
Assess and treat the risk factors - e.g. smoking
How do you treat a retinal detachment
If picked up as early retinal tear can be lasered to prevent progression to proper detachment
Vitrectomy – similar to keyhole in the eye, clear away the vitreous gel, laser the initial tear and put a bubble of gas in to hold retina in place while things heal
What is retrobulbar neuritis
Similar to optic neuritis except the inflammation is behind the optic nerve head so cannot be seen
Which eye symptoms and signs can suggest a neurological issue
Optic nerve function – acuity, visual field, colour vision, pupil response
Ocular motility – 3rd, 4th, 6th nerve palsies
What investigations should be done for bilateral papilloedema
Suggests raised ICP
Needs urgent imaging to rule out SOL
If no SOL you may be looking at IIH which can be diagnosed by LP
How do you trea optic/retrobulbar neuritis
IV steroids may hasten recovery but not affect final VA. Oral steroids may worsen outcome
May be role for B Interferon
What can cause Horner’s syndrome
Pancoast tumour Carotid/Aortic aneurysms Lesions of neck Congenital Idiopathic
Anything affecting the sympathetic chain
Horizontal field defects are seen when which part of the tract is affected
Anything in front of the chiasm
Vertical field defects are seen when which part of the tract is affected
Structures behind the chiasm
What is a hyphaema
Fluid level of blood in the eye
What is a hypopyon
Fluid level of white blood cells in the eye
Sign of severe intra-ocular infection
