Ophthamology Flashcards
What is it called when the red reflex is white in kids and what could it be due to?
Leuccocoria
Retinoblastoma or congenital cataracts *
Retinal detachement, retinopathy of prematurity, uveitis
How might Retinoblastoma present?
at 12 months if hereditary, 24 months if sporadic
Loss of red reflex (leuccocoria), strabismus, reduced vision, red eye
Knudsens 2 hit hypothesis
Tumour of retinoblasts
Why must congenital cataracts be managed urgently?
Can cause Amblyopia - halting of central vision development
What is the most common cause of conjuntivitis in neonates?
Chlamydia trachomatis
What is conjuntivitis/ sticky eye(s) in the first month of life called? What are some causes?
Ophthalmia neonatorum
Gonococcal - 1-3 days (risk of blindness)
Chalymidial - 4 - 24 days - most common
Bacteria, HSV
When is myelination of the optic nerve complete?
24 months
When is the eye structurally completely developed?
3 years
What is amblyopia?
Halting of central visual development due to poor vision before ~8 years old
What is Retinopathy of prematurity?
In premature babies, the peripheral retina is not vascularised at birth. There is growth of new blood vessels and scarring. 5 stages in classification
What classes you as partially sighted?
Acuity of 6/60 or worse or 6/60 or better but with visual field restriction
What classes you as blind?
Acuity of 3/60 or worse with a full visual field or 3/60 or better with substantial visual field loss
What is blepharitis?
Inflammation of the eyelid margin secondary to blockage of the meibomian glands (oil secreting) and infection with staph aureus
Redness and irritation of the eye and lid ± marginal keratitis
What is a chalazion and what is a stye?
Chalazion is a swollen blocked meibomian gland. It is hard and non-tender
Stye is a infection of the glands of moll (sweat) or glands of zeis (sebaceous) and it is tender and red
What is lagophthalmos?
Inability to close the eyelids
What is the difference between Periorbital and orbital cellultius and how can you differentiate?
Periorbital - eyelid skin in front of oribital spetum
Orbital - tissue behind orbital septum involved
Orbital is sight and life threatening - CT scan
Orbital Sx - pain on eye movement, changes in vision, abnormal pupillary reactions, proptosis *
Give some examples of sudden and gradual vision loss.
Sudden - Retinal detachement, Wet ARMD, retinal artery or vein occlusion, optic neuritis (central scotoma)
Gradual - cataracts, glaucoma, dry ARMD, diabetic retinopathy
Give some examples of sudden painless vision loss.
Anterior ischaemic optic neuropathy Retinal vein or artery occulsion Wet ARMD Retinal detachement Vitreous haemorrhage Severe uveitis
Give some examples of sudden painful vision loss.
Acute glaucoma, Severe uveitis, optic neuritis, endophthamlitis, severe corneal pathology
What part of your vision does glaucoma affect?
Peripheral
What is normal Intra-ocular pressure?
10-24mmHg
Measured using a Tonometer (goldmann’s)
Explain what an Acute angle closure glaucoma is?
Emergency.
There is a sudden increased in IOP (>/= 30mmHg) due to blockage of the trebecular meshwork where aqueous humorous should drain, due to the iris pressing forward and blocking it. This casues increased pressure that pushes back on the eye causing death of axones at the periphery first (works in like until left with tunnel vision) –> Increased cup:disc ratio
How might a patient with Acute angle closure glaucoma present?
Generally unwell with N&V, onset hr-days Severely painful red eye Blurred vision Halos around lights at night Headcache
What signs might a Acute angle closure glaucoma patient have?
Reduced VA, red eye, corneal haze, mid-dilated and fixed pupil, high IOP digitally, closed iridocorneal angle on goniscopy
For AACG you can give Pilocarpine, what does this do?
Constricts the sphincter muscles of the iris and so the pupil. This helps open the angle and so allows for better drainage
What is Open angle glaucoma?
Chronic due to gradual increase in resistance in the trabecular meshwork causing reduced outflow
Usually asymptomatic and diagnosed by routine screening
What drugs can be used to lower the aqueous humour production in Glaucoma?
Beta blockers (timolol) SE - bradycardia, bronchoconstriction
Carbonic anhydrase inhibitors (Brinzolaminde) SE - malaise, metallic taste
Alpha 1 agonist (Brimonidine) SE - allergy, dry mouth
What drugs can be used to reduce the uveoscleral outflow in glaucoma?
Alpha 1 agonist (Brimonidine) SE- allergy, dry mouth Prostaglandin anagloue (Latanoprost) SE - eyelash growth, iris pigmentation
What is retinal detachement?
When the retinal separates from the choroid
Usually due to a retinal tear allowing vitreous fluid into the space
How might a patient with retinal detachment present?
4 F’s
Floaters and flashed, fall in acuity, field loss
(peripheral vision loss, like a shadow coming across vision. Painless)
tx - surgery
What causes Retinal artery occulsion?
Usually due to an emboli or GCA*
How might a patient with retinal artery occlusion present?
Sudden painless loss of vision
RAPD
Pale retina with a cherry red fovea
What does Central retinal vein occlusion look like on fundoscopy?
Flame or blot haemorrhages, Macular oedema, optic disc oedema
What might indicate Anterior ischaemic optic neuropathy on fundoscopy?
Pale, swollen optic disc
What might be the underlying cause for a vitreous haemorrhage?
Retinal tears or detachment
Trauma
Neovascularisation (2’ RVO or diabetic retinopathy)