Station 2/5: Eye Flashcards
features of hypertensive retinopathy?
grade 1: anteriolar thickening, tortuosity, silver wiring
grade 2: + arteriovenous nipping
grade 3: + flame or blot haemorrhages and cotton wool exudates
grade 4: + papilloedema
features of clinically significant macular oedema?
hard exudates at / near the macula (assoc w thickening of adjacent retina)
or
areas of retinal thickening 1 disc area or larger, located within 1 disc diameter of the centre of the macula
or
thickening of the retina at or within 500 micros of centre of the macula
*retinal thickening cannot be seen on direct ophthalmoscopy
features of proliferative diabetic retinopathy
neovascularization
vitreous/preretinal haemorrhage
early PDF: new vessels
high risk PDR: neovascularisation of disc >/=1/3 to 1/3 of disc area
or neovasc of disc & vitreous or pre-retinal haemorrhage
or neovasc elsewhere >= 1/2 disc area and vitreous or pre-retinal haemorrhage
severe PDR: posterior fundus obscured by preretinal or vitreous haemorrhage or centre of macula detached
features of non proliferative diabetic retinopathy
microaneurysms
soft exudates (cotton wool spots)
retinal haemorrhage
venous beading
intraretinal microvascular abnormalities
features of mild non proliferative diabetic retinopathy?
at least 1 microaneurysm
features of moderate non proliferative diabetic retinopathy?
haemorrhage/ microaneurysm >= standard photo #2A or
soft exudates (cotton wool spots), venous beading and intra retinal micorvasc abnormalities
features of severe non proliferative diabetic retinopathy? aka pre-proliferative diabetic retinopathy
haemorrhage/ microaneurysm in all 4 quadrants
or
venous beading in at least 2 quadrants
or
intraretinal microvasc abnormalities at least 1 quadrant
features of very severe non proliferative diabetic retinopathy?
aka severe pre-proliferative diabetic retinopathy
2 or more signs of severe NPDR
to present on diabetic retinopathy, mention…
non proliferative/ pre-proliferative/ proliferative diabetic retinopathy
with or without macular oedema
presence of focal/ pan retinal/ macular photocoagulation scars
complications of:
vitreous haemorrhage
fibrosis with retinal detachment
optic atrophy
associated findings (if any):
hypertensive retinopathy changes
rubeosis iridis
cataracts
xanthelasma
how soon to refer eye for diabetic retinopathy?
pre-proliferative: TCU within 13 wks
proliferative: TCU within 2 weeks
driving in the context of diabetic retinopathy?
driving with group 1 license is allowed after laser photocoagulation, but requires DVLA notification
this will require visual field testing which will be arranged by the DVLA
what is retinitis pigmentosa?
dystrophy of the photoreceptors and pigment epithelium
occurs bilaterally, begins in childhood/ young adults with a progressive course
inheritance of retinitis pigmentosa?
9% X linked
16% auto recessive
22% auto dom
rest or approx 50% sporadic
clinical features of retinitis pigmentosa?
commoner rod-cone type:
ring scotoma
peripheral visual field loss, tunnel vision
night blindness
cone-rod type:
visual acuity loss
loss of color discrimination
causes of retinitis pigmentosa?
primary with no known cause
secondary to inflammatory retinitis
assoc with other syndromes:
- Usher’s syndrome (RP with hearing loss)
- Alport’s syndrome (RP with hearing loss and nephritis)
- Refsum disease (RP with hearing loss, cerebellar ataxia, hypertrophic peripheral neuropathy, ichythyosis)
- Abetalipoproteinaemia
- Friedrich’s ataxia
- Kearns Sayre syndrome
- Laurence Moon Biedl syndrome
what are the associated ocular abnormalities in retinitis pigmentosa?
posterior subcapsular cataracts
myopia
keratoconus: degenerative disorder of the eye in which structural changes within the cornea cause it to thin and change to more conical shape
open angle glaucoma
how would u investigate retinitis pigmentosa?
careful family history and rule out phenothiazine toxicity
formal visual fields testing, color testing (ishihara charts), and electroretinogram (ERG)
ix if cause is suspected e.g. Lipid and protein electrophoresis for abetalipoproteinaemia, serum phytanic acid for refsum disease
management of retinitis pigmentosa?
education and genetic counselling
impaired vision training and aids for ADL and job retraining
medication such as high dose Vit A which slows the progress of RP by 2% a year and acetazolamide for complications of cystoid macular oedema
Retinitis pigmentosa with short stature, polydactyly, renal dysfunction
Laurence moon biedl syndrome
Retinitis pigmentosa with external ophthalmoplegia, ptosis and heart block
Kearnes sayre syndrome
Retinitis pigmentosa, cerebellar ataxia, spastic paraparesis, dorsal column loss
a/w scoliosis, pes cavus, DM, AF, hypertrophic CMP, optic atrophy, learning impairment
Friedreichs ataxia
- auto recessive, chr 9
retinitis pigmentosa with fat malabsorption and spinocerebellar degeneration
abetalipoproteinaemia
retinitis pigmentosa with hearing loss
ushers syndrome
retinitis pigmentosa with hearing loss and nephritis
alports syndrome
retinitis pigmentosa with hearing loss, cerebellar ataxia, hypertrophic peripheral neuropathy, ichthyosis
refsum disease
- auto recessive
- phytanic acid storage disease
- raised CSF protein levels in the absence of pleocytosis
history taking in retinitis pigmentosa?
loss of visual acuity
VF loss-tunnel vision, ring scotoma
loss of color discrimination
night blindness
assoc syndromes:
- diplopia, ptosis
- hearing loss
- cerebellar signs - poor coordination and unsteady gait
- limb numbness/ weakness, ask for childhood onset
- renal disease
pmh: myopia, cataracts, glaucoma, cardiac arrhythmia
FHx
examination of retinitis pigmentosa?
screen for VA with finger counting, then test with snellen chart
cataracts
keratoconus
pupils: direct, indirect, RAPD
Fundoscopy:
- RP: pigmented bony spicules at the peripheries
- macular oedema or bulls eye maculopathy (complication)
- attenuated arterioles
- optic atrophy: pallor of optic disc (a/w friedrich’s ataxia)
visual field: tunnel vision/ ring scotoma
eye movemetns: external ophthalmoplegia (a/w kearnes sayre syndrome)
cranial nerves:
- ptosis (KSS)
- deafness (ushers, alports, refsums)
others:
sallow appearance and pedal oedema for renal impairment (lawrence-mood-biedl, alports)
skeletal: hands for polydactyly and short staturs (LMB), scoliosis (Friedrich’s ataxia)
myopia if glasses available
retinitis pigmentosa: how to complete your examination
formal visual field and acuity testing
neuro examination for cerebellar sings, long tract signs esp dorsal columns and pyramidal tract in friedrich’s ataxia
history for any renal disease, hearing loss, or family history of congenital disorders
to present for retinitis pigmentosa, important negatives for underlying aetiology
- no ptosis/ ophthalmoplegia to suggest underlying Kearnes sayre syndrome
- no hearing loss to suggest Refsum, usher’s or alports
- not sallow, and no short stature/ polydactyly to suggest laurence-mood-biedl syndrome
- no optic atrophy or scoliosis to suggest underlying friedreich’s ataxia
Examination in optic atrophy
Fundus
• Optic atrophy - pale disc with sharp margins
Aetiology
• Papilloedema - intracranial SOL
• Optic cup - cup:disc ratio normally 0.3. Possible glaucoma if > 0.5
• DM changes
• Retinitis pigmentosa
• Attenuated arterioles and veins as in CRAO / AION
Eye
• RAPD positive
• Central scotoma on visual field testing
Aetiology
• Argyll-Robertson pupil (syphilis)
• Astamus (MS and FA)
Head
• Tender temporal arteritis
• Pb lines in the gums
• Paget’s facies
Hands
• Cerebellar (MS and FA)
• AF (thromboembolic CRAO)
Presentation of optic atrophy
Unilateral/ bilateral
Features of optic atrophy:
pale optic disc with sharp margins, which is associated with relative afferent pupillary defect and central scotoma
Aetiology:
I did not detect any presence of papilloedema, deep optic cup, DM changes or RP.
The vessels are also not attenuated.
To complete examination:
testing patient’s visual acuity and visual fields, as well as for features of MS such as INO, nystagmus, cerebellar signs and long tract signs.
I would also like examine the temporal artery for tenderness which would suggest giant cell arteritis, examine the gums for Pb lines, and feel the pulse for AF.
Likely scenarios in paces with optic atrophy
- OA with MS
- OA with Retinitis pigmentosa
- OA with CVRF and AION
- OA with Temporal arteritis
Causes of unilateral optic atrophy
• Demyelinating disease (ie MS)
• Compression (Tumor, aneurysm, Paget’s)
• Glaucoma
• Ischaemic
—— Thromboembolic (Central retinal artery occlusion CRAO)
—— vasculitis: temporal arteritis, tertiary syphilis
—— anterior ischaemic optic neuropathy
Ischaemic causes of unilateral optic neuropathy
- Thromboembolic (Central retinal artery occlusion CRAO)
- vasculitis: temporal arteritis, tertiary syphilis
- anterior ischaemic optic neuropathy
Types of anterior ischaemic optic neuropathy?
Arteritic AION- secondary to temporal arteritis. Emergency, treat with steroids
Non arteritic AION- secondary to crowding of optic disc + CVRF leading to ischaemia. Can attempt to tx w steroids, control CVRF
Causes of bilateral optic atrophy
Toxic:
- drugs (ethambutol, chloroquine, methanol, Pb, Arsenic)
- nicotine, alcohol
Metabolic:
- B12 deficiency, B1 and B6
- diabetes mellitus
Hereditary:
- Friedreich’s Ataxia
- Leber’s Hereditary Optic Neuropathy (LHON)
- DIDMOAD (DI, DM, optic atrophy, deafness) aka Wolfram syndrome
others:
- 2’ papilloedema
- 2’ retinitis pigmentosa
What drug causes may lead to bilateral optic atrophy
Ethambutol, chloroquine, methanol, Pb, Arsenic
What metabolic causes of optic atrophy are there
B12 deficiency, B6, B1
DM
What is Leber’s Hereditary Optic Neuropathy?
Mitochondrial disease with point mutations to mtDNA
Presents w visual loss, onset usually in young adulthood, usually in one eye progressing to bilateral wks-mths later
- Hereditary condition affecting males
• Progressive visual loss
• Onset form second decade onwards
• Mitochondrial disease with point mutations
Mx of Lebers Hereditary Optic Neuropathy
Genetic counselling
early introduction to visual aids and occupational therapy
Avoid alcohol, tobacco, ethambutol
Ix of optic atrophy
Confirm optic atrophy:
• Electroretinography and pattern evoked visual response
Ix for Aetiology
Bloods:
• Blood glucose - DM
• ESR - temporal arteritis
• VDRL
• B12 levels
Imaging
• Skull XR - enlarged sella turcica - pit tumour
• CT scan: SOL pituitary fossa, optic foramina/sinus, intraorbital area
• mri for demyelinating disease for MS
Ecg for AF
History for toxic and hereditary causes
