Posterior eye opthal conditions Flashcards
(10 cards)
POSTERIOR VITREOUS ATTACHMENT
i) what is the vitreous body? what does it do? what happens to it with age? what happens in PVD?
ii) who is it most common in? is it painful? name three symptoms patients may present with?
iii) what tx is given? what can it presdispose patients to?
iv) what is it important to exclude? how is this done?
i) vitreous body is gel inside the eye that maintains structure, keeps retina pressed on choroid
made of collagen and water
with age = less firm and less able to main shape
PVD - vitreous gel comes away from retina
ii) common in elderly
painless, spots of vision loss, floaters, flashing lights
iii) no tx needed - can pre dis to retinal tears and detachment
iv) exclude retinal tear or detachement > assess retina by opthalmologist
RETINAL DETACHMENT
i) what happens? what is it usually due to? what does the outer retina rely on for blood supply? what can detach therefore cause?
ii) name five risk factors? is it painful?
iii) name three ways it may present what should be done first in mx?
iv) how are retinal tears managed? what does mx of detachment aim to do? name three ways this can be done
i) retina seperates from choroid underneath > usually due to a retinal tear that allows vitreous fluid to get under the retina and fill the space
outer retina relies on bv of choroid for blood supp > therefore sight threatening
ii) RF = post vitreous detachement, diabetic retinopathy, eye trauma, retinal malignancy, older age, FH
painless
iii) px - peripheral visual loss (shadow across vision), blurred/distorted vision, flashers and floaters
immed refer to opthalmology
iv) tear - create adhesion between retina and choroid to prevent detach > laser or cryotherapy
detaaach - reattaach and reduce any traction to prevent it hppening again
do this by - vitrectomy (removing vit body and replacing with oil or gas)
scleral bulking (pressure on sclera so choroid is brought into contact with retina)
pneumatic retinopexy (inject gas bubble into vitreous body that flattens retina against choroid and prevents detach)
RETINAL VEIN OCCLUSION
i) what happens? where does the retinal vein run? what does it do?
ii) how many branches form the CRV? what does blockage cause? name two things that can be a consequence of this? which signalling molecule is released?
iii) how does it present? name four RF
i) thrombus forms in retinal veins and blocks blood drainage from the retina
runs through the optic nerve
ii) four branches join to make the central retinl vein - blockage causes pooling of blood in the retina > leakage of fluid > macula oedema aand retinal haemmorhages
results in damage to retinal tissue and loss of vision
release of VEGF > neovasc
iii) present with sudden painless loss of vision
Rfs - hypertension, high choles, diabetes, smoking, glaucoma, systemic inflam eg SLE
RETINAL VEIN OCCLUSION DX AND MX
i) name three findings on fundoscopy?
ii) name five bloods that should be done
iii) what should be done if RVO is suspected? what two things does mx in secondary care aim to do?
iv) name three ways it can be managed
i) flame/blot haemmorhages, optic disk oedema, macula oedema
ii) full medical hx, FBC (leukaemia), ESR (systemic inflam), BP (hypertension), serum glucose (diabetes)
iii) urgent opthal referral
aim to treat macula oedema and prevent complications eg neovaaasc of retinaa and iris and glaucoma
iv) laser photocoag
intraviteal steroids eg dex
anti VEGF eg ranibizumab and bevacizumab
CENTRAL RETINAL ARTERY OCCULUSION
i) what happens? what is it a branch of? (2)
ii) what is the most common cause of occlusion? name another cause?
iii) name four risk factors? which two conditions put patients at a higher risk?
iv) what does blockage cause? what pupil defect may be seen? explain
v) what will be seen on fundoscopy? (2) why
i) central retinal artery flow is blocked
branch of opthalmic artery branch of internal carotid
ii) commonly due to atherosclerosis
giant cell arteritis - vasculitis affects opthalmic or central retinal artery > reduced blood flow
iii) older age, family hx, smoking, ETOH, hypertension, diabetes, poor diet, obesity
giant cell arteritis and PMR
iv) blockage causes sudden painless loss of vision
relative afferent pupillary defect (RAPD) - swinging light reflex
affected pupul constricts more when light is shone in the opposite eye (due to consensual reflex - aff eye cant detect light as well so brighter when shone in other eye)
v) fundoscopy - pale retina and cherry red spot
pale retina - lack of perfusion
cherry red spot is macula
MX OF CENTRAL RETINAL ARTERY OCCLUSION
i) what needs to be done first? what is an important reversible cause? therefore what two tests should be done? what is the tx for this
ii) what should be attempted in immediate mx? name four ways this can be done?
iii) what is long term mx?
i) refer to opthalmology
giant cell arteritis > ESR and temporal artery biopsy
treat with prednisolone (high dose)
ii) attempt to dislodge the thrombus - ocular maassage, remove fluid from ant chamber to reduce pressuresm inhale carbogen to dilate artery, isosobide dinitrate to dilate the artery
RETINITIS PIGMENTOSA
i) what is it? why does it cause night blindness? which type of vision is decreased? (2)
ii) what is very important in the history? what is usually the first symptom? which type of vision is lost first? what type of diseases are associated with it?
iii) what will fundoscopy show? where may pigmentation be seen? how may the optic disk appear?
iv) name four aspects of general mx?
v) name three things that may slow disease progression
i) inherited congenital condition where degeneration of rods and cones in retina
rods degen more than cones > night blind
decreased central and peripheral vision
ii) family hx
night blind is usually first then periph lost before central cision
assoc with systemic diseases
iii) fundoscopy > pigmentation - bone spicule
pigmentation conc aaround mid peripheraal retina
waxy or pale optic disk
iv) refer to opthaal, genetic counsel, vision aids, sunglasses to protect retina, driving limitations, regular vision assessments
v) vitamin and antioxidant supp, oral acetazolamide, steroid injections, anti VEGF
PAPILLOEDEMA
i) what is it? is it usually uni or bilateral?
ii) name four features seen on fundoscopy
iii) name four causes
i) optic disc swelling that is caused by increased intracranial pressure. It is almost always bilateral.
ii) venous engorgement: usually the first sign
loss of venous pulsation: although many normal patients do not have normal pulsation
blurring of the optic disc margin
elevation of optic disc
loss of the optic cup
Paton’s lines: concentric/radial retinal lines cascading from the optic disc
iii) space-occupying lesion: neoplastic, vascular
malignant hypertension
idiopathic intracranial hypertension
hydrocephalus
hypercapnia
VITREOUS HAEMMORHAGE
i) what is it? what does it cause? where can the source of bleeding come from? how quickly is blood cleared after bleeding stops?
ii) name three common causes?
iii) name three ways patients present? how is visual acuity affected? what can be seen if there is severe haemm?
iv) what may be seen on fundoscopy? whaat can be seen on slit lamp exam? which imaging may be useful?
v) what is used to look for neovasc
i) bleeding into vit humour - common cause of sudden painless vision loss
source from any vessel in retina
mild = flashers and floaters
blood cleared at 1% per day
ii) prolif diabetic retinopathy, post vit detaacch, ocular trauma
iii) px with painless vision loss, ghaze, red hue in vision, floaters/shadows/spots in vision
iv) fundo - haemmorhage
slit - RBC in ant vitreous
US to rule out retinal tear or detach
orbit CT if injury
v) fluorescein angiography to ident neovasc
SQUINT
i) what is it? what can it lead to if undetected?
ii) how can it be dx? what are the two types
iii)) how can it be managed
i) misalignment of the visual axes
can lead to amblyopia - brain favours inputs from one eye
ii) dx with corneal light reflection test - hold light source 30cm from face to see if it reflects symm on pupils
concominant - imbalance of extraoc muscles
paralytic - paralysis of extra ocular musclles
iii) mx by refer and may patch one eye to prevent amblyopia
