Ophthalmology Flashcards
(109 cards)
1
Q
accomodation
A
changing of lens shape to focus on near objects
uses the ciliary muscle
2
Q
acuity
A
a measure of how well the eye sees a small or distant object
3
Q
Amblyopia
A
decreased acuity uncorrectable by lenses, with no anatomic defect
4
Q
amsler grid
A
test chart of intersecting lines used for screening for macular disease
- lines appear wavy, squares distorted
5
Q
anisocoria
A
unequal pupil size
6
Q
ansiometropia
A
different refractive errors in each eye
7
Q
aphakia
A
the state of having no lens- e.g. removed because of cataracts
8
Q
blepharitis
A
inflamed lids
e.g. staphs, seborrhoeic dermatitis or rosacea
burning itching red margins, scales on the lashes
Treatment- good hygiene- cotton bud and baby shampoo. children- consider oral erythromycin (blepharokeratitis)
9
Q
canthus
A
the medial or lateral angle made by the open lids
10
Q
chemosis
A
oedema of the conjunctiva
11
Q
choroid
A
vascular coat between the retina and the outer scleral coat
12
Q
ciliary body
A
portion of uvea (uveal tract) between iris and choroid
contains the ciliary procresses and ciliary muscle (for accomodation)
13
Q
conjunctiva
A
mucous membrane on anterior sclera and posterior lid aspect
14
Q
cycloplegia
A
ciliary muscle paralysis preventing accomodation
15
Q
dacrycocystitis
A
inflammation of lacrimal sac
16
Q
dioptre
A
units for measuring refractive power of lenses
17
Q
ectropion
A
lids evert (esp. lower lid) causes eye irrititation, watering ± keratitis
associated with old age and facial palsy
plastic surgery to correct deformity
18
Q
entropion
A
lids invert (lashes may irritate eyeball) typically due to degeneration of lower lid fascial attachements
treat with botulinum toxin and then surgery
19
Q
epiphora
A
passive overflow of teas onto the cheek
20
Q
fornix
A
where bulbar (scleral) and palpebral (lid) conjunctiva meet
21
Q
fovea
A
cone rich area of macula, capable of 6/6 vision
22
Q
fundus
A
part of the retina normally visible through the ophthalmoscope
23
Q
keratoconus
A
cornea shaped like a cone
24
Q
keratomalacia
A
the cornea is softened
25
limbus
annular border between clear cornea and opaque sclera
26
macula
retinal area ~5mm across, lateral to optic disc
27
miotic
agent causing pupil constriction (e.g. pilocarpine)
28
mydriatic
an agent causing pupil dilatation (e.g. tropicamide)
29
near point
where the eye is looking when maximally accommodated
30
optic cup
cup like depression in the centre of the optic disc
31
optic disc
part of the optic nerve seen ophthalmoscopically in the fundus
32
papillitis
inflammation of the optic nerve head
33
presbyopia
age-related reduced near-acuity from failing accommodation
34
pterygium
wing shaped degenerative conjunctival condition
35
ptosis
drooping lids
36
refraction
ray deviation on passing through media of different density, or determining refractive errors and correcting them with lenses
37
retinal detachment
sensory retina separates from the pigmented epithelial layer of retina
38
sclera
the whites of the eyes starting from the corneal perimeter
39
scotoma
a defect causing a part of the field of view to go missing
40
slit lamp
a device that illuminates and magnifies structures in the eye
41
stabismus
squint
| eyes deviate
42
tarsorrhaphy
surgical procedure to unit upper and lower lids
43
tonometer
device for measuring intraocular pressure
44
uvea
iris, ciliary body, choroid
45
vitrectomy
surgical removal of the vitreous
46
vitreous
jelly like substance filling the globe behind the lens
47
Stye
Hordeolum externum
abscess or infection - usually staphylococcus in a lash follicle (also glands of Moll (sweat) or Zeis (sebum))
point outwards
apply warm compress 5-10 mins, several times a day until resolution
Residual swelling called a chalazion
48
Pinguecula
degenerative vascular yellow-grey on conjunctiva either side of the iris
- associated with increases in hair and skin pigment, sun-related skin damage
49
lagophthalmos
difficulty in lid closure
- causes exophthalmos, mechaincal impairment of lid movement, leprosy, paralysis of obicularis oculi
lubricate eyes with liquid parafin ointment
50
Retinoblastoma signs
stabismus and leukocoria (white pupil)
| always suspect when red reflex is absent
51
retinoblastoma inheritance
autosomal dominance - 80% penetrance
| RB gene is present in everyone - normally suppressor gene or anti-oncogene
52
Associations with retinoblastoma
5% occur with pineal or other tumour (trilateral retinoblastoma)
secondary malignancy- osteosarcoma and rhabdomyosarcoma - main cause of death
53
Treatment of retinoblastoma
enucleation (eye removal) - traditional. Large tumours, long standing retinal detachment and optic nerve invasion or extrascleral extension
chemotherapy - useful in bilateral tumours
external beam radiotherapy
ophthalmic plaque brachytherapy - focal and shielded radiation
cryotherapy and transpupillary thermotherapy- control of small selected small tumours
54
ophthalmic shingles
pain and neuralgia V1 distribution
blistering inflammed rash
treat with oral antivirals within 72 hours of rash onset
55
orbital cellulitis
infection of soft tissues posterior to orbital septum
spread from paranasal sinus infection (eyelid, dental injury/infection or external ocular infection
- inflammation in orbit, fever, id swelling, decreased eye mobility±diplopia. May have chemosis and proptosis
56
Associated complications of orbital cellulitis
subperiosteal and orbital abscess
extra-orbitalextension
visual loss from optic neuritis/ central retinal vein or artery occlusion
intra-cranial involvement --> meningitis, brain abscess, thrombosis in dural or cavernous sinus
57
Treatment of orbital cellulitis
CT, ENT & ophthalpic opinion
Antibiotics
rule out underlying rhabdomyosarcoma, grave's disease or cavernous sinus thrombosis
58
Preseptal (periorbital) cellulitis
infection of soft tissues anterior to the orbital septum
commonly caused by sinusitis or facial skin lesions - insect bites, trauma
characterised by acute erythematous swelling of the eyelid.
no- painful eye movements, diplopia or visual impairment
Rx- empirical treatment of cellulitis e.g. amoxicillian 1g TDS 7-10days
59
Convergent squint
esotropia
commonest in children
may have no cause or due to hypermetropia
strabismic amblyopia the brain supresses the deviated image, visual pathway does not develop normally
60
divergent squint
exotropia
occurs in older children
| often intermittend
61
Non-paralytic squints
usually start in childhood
| may be constant or not
62
Diagnosis of squint
1. corneal reflection - reflection from bright light is asymmetrical if squint present
2. cover test - movement of uncovered eye to ttake up fixation as the other eye is covered= manifest squint
latent squint = movement of the covered eye as cover is removed
63
Management of squint
3 O's
O - optical - assessment, spectacles
O - orthoptic - patch the good eye
O - operation - resection and recession of rectus muscles
64
Paralytic squints
diplopia most on looking in the direction of pull of the paralysed muscle
separation of two images is greatest when the image from the paralysed eye is furthest from the midline and faintest
65
third nerve palsy
occulomotor
ptosis, proptosis (reduced recti tone), fixed pupil dilatation
eye looks out and down
Causes- cavernous sinus lesions, superior orbital fissure syndrome, DM, posterior communicating artery aneurysm
66
fourth nerve palsy
trochlear
diplopia
ocular torticollis - patient holds head tilted
eye looks upward, in adduction and can't look down and in (superior oblique paralysed)
causes - trauma, tumour, idiopathic
67
Sixth nerve palsy
abducens
diplopia in horizontal plane
medial deviation. cannot move laterally from the mid line
lateral rectus is paralysed
Causes- tumour causing increasing ICP, basal skull trauma, MS
68
Horner's syndrome
disruption in sympathetic fibres
pupil is miotic (smaller)
no dilatation in the dark and partial ptosis
unilateral facial anhydrosis = lesion proximal to carotid plexus
69
Causes of Horners syndrome
- posterior inferior cerebellar artery or basilar artery occlusion
- multiple sclerosis
- cavernous sinus thrombosis
- pancoast tumous
- hypothalamic lesions
- cervical adenopathy
- mediastinal masses
- pontine syringomyelia
- Klumpke's palsy
- aortic anuerysm
70
Subconjunctival haemorrhage
harmless but alarming
pool of blood behind the conjunctiva
- check BP
71
episcleritis
inflammation below conjunctiva
often seen with an inflammatory nodule
sclera look blue below a focal, cone shaped wedge of engorged vessels
eye aches duly
Rx- symptomatic relief - artificial tears , topical or systemic NSAIDs
72
scleritis
generalised inflammation of sclera with oedema of conjunctiva , scleral thinning and vasculitic changes
associated with systemic disease
constnat severe dull ache boring into eye
may present with headache and photophobia
may be necrotising
73
Uveitis
pigmented part of the eye- iris, ciliiary body, choroid
anterior - iris & ciliary body
posterior - choroid
intermediate - vitreous
74
Anterior uveitis
ank spon, sarcoid, behçets, IBD, reactive arthritis, herpes, TB
Presentation - red eye, pain, blurred vision and photophobia
increased lacrimation
treat cause
75
acute closed angle glaucoma
angle of anterior chamber narrows acutely causing sudden rise in intraocular pressure >30mmHg
pupil becomes fixed and dilated- axonal death occurs
raised intraocular pressure makes the eye feel hard
76
Presentation of acute closed angle glaucoma
generally unwell with N&V
| headache and painful eye- blurred vision, haloes around lights at night
77
Treatment of acute closed angle glaucoma
```
b-blockers tried
pilocarpine
IV acetazolamide
analgesia and antiemetics
peripheral iridectomy once IOP is controlled
```
78
Complications of acute closed angle glaucoma
visual loss
central retinal artery or vein occlusions
repeated episodes
79
Conjunctivitis
red and inflammed conjunctiva
hyperaemic vessels may move over sclera
eyes itch, burn and lacrimate
often bilateral with discharge sticking lids together
80
non-infective causes of conjunctivitis
```
allergic conjunctivitis
toxic
autoimmune
neoplastic
contact lenses - reaction to foreign substance
```
81
infective causes of conjunctivitis
non-herpetic viral - serous discharge
| bacterial
82
Treatment of bacterial conjunctivitis
if sexual disease, contact lens wearer or immunocompromised
chloramphenicol or fusidic acid drops
83
Anterior ischaemic optic neuropathy
most common cause of optic neuropathy in older patients
| optic nerve is damaged if vascular supply to optic nerve is blocked by inflammation or atheroma
84
Retinal vein occlusion
incidence increases with age
2nd most common cause of blindness from retinal vascular disease
Accosicaed with aterioscleroisis, high BP, DM and polycythemia
Rx- intravitreal anti-VEGF therapy, dexamethosone implants
85
Vitreous heamorrhage
arise from retinal neovascularisation, retinal tears, retinal detachment or trauma
small extravasation of blood produce vitreous floaters
Check - acuity, pupil reaction, fundi
normally spontaneously resolves
may need vitrectomy in dense haemorrhage
86
Optic neuritis
subacute loss of vision
unilateral loss of acuity occurs over hours or days
colour vision is affected- red desaturation
painful eye movements
full recovery over 2-6 weeks
45-80% develop MS in the next 15 years
other causes- syphilis, leber's optic atrophy, DM, vitamin deficiency
Rx- methylprednisolone IV 72hrs then prednisolone PO for 11 days
87
Wet age related macular degeneration
exudative
pathologic choroidal neovascular membranes develop under the retina
- leak fluid and blood causing a central disciform scar
vision deteriorates rapidly - distortion is key
fluid exudation, localised detachment of pigment
Treatment- smoking cessation, diet rich in green leafy veg, VEGF inhibitors- bevacizumab, laser photocoagulopathy, photodyamic therapy, intravitreal steroids
88
Dry age related macular degeneration
non-exudative
much slower - over decades, progressive visual loss
aetiology not well known
dursen --> optic nerve head axonal degeneration (leads to intracellular mitochondrial calcification- some axons then rupture --> calcium deposition in the extracellular space)
optic disc is made irregular and lumpy by these deposits
optic cup is absent
abnormal branching vessel patterns
89
Chronic simple open-angle glaucoma
optic nueropathy with death of many retinal ganglion cells and their optic nerve axons
IOP may be raised but this isn't part of the definition
asymptomatic until visual fields are badly impaired
90
Diagnosis of chronic simple open-angle glaucoma
```
IOP measurement using tonometry
Central corneal thickness measurement
Peripheral anterior chamber configuration and depth assessments using gonioscopy
visual field measurement
optic nerve assessment
```
91
High risk for chronic simple open-angle glaucoma
need screening
```
>35
+ve family history esp. siblings
African-Carribean
myopia
diabetic/thyroid eye disease
```
92
Drug treatment for chronic simple open-angle glaucoma
aim to reduce production of aqueous or increase uveoscleral outflow
- prostaglandin analogues- latanoprost
- B-Blockers - timolol or betaxol
- a-adrenergic agonists - brimonidine, apraclondine
- carbonic anydrase inhibitors - dorzolamide& brinzolamide
- miotics - pilocarpine
sympathomimetic dipiverfrine
-fixed dose combination drops
laser therapy or surgery
93
Risk factors for cataracts
age related
genetic
occur early in DM
associated wtih smoking, alcohol excess, sunlight exposure, trauma, radiotherapy, HIV+ve
94
Nuclear cataracts
change the lens refractive index and dulls colours
95
Cortical cataracts
spoke like wedge shaped opacities
| milder effects on vision
96
Posterior subcapsular cataracts
typically progress faster and cause glare from sunlight and lights when driing at night
97
Presentation of cataracts
blurred vision
unilateral cataracts often unnoticed
loss of stereopsis - affects distance judgement
bilateral cataracts cause painless loss of vision ± mononuclear diplopia
98
Post-op complications of cataract surgery
posterior capsule thickening
| astigmatism becomes more noticeable
99
Retinal detachment
types
1. Rhegmatogenous retinal detachment - fluid passes into vitreous space- caused by trauma
2. Exudative retinal detachment - no trauma
3. Tractional retinal detachments - pulling on retina. more common in myopic eyes
100
Presentation of retinal detachment
4 F's
1. Floaters
2. Flashes
3. Field Loss
4. Fall in acuity- painless, curtain falling over the vision
101
Management of retinal detachment
nurse -flat or 30 degree up head tilt (inferior)
laser photocoagulation therapy
vitrectomy and gas tamponade with scleral silicone implants
cryotherapy or laser coagulation to secure the retina
102
Structural eye changes in DM
ocular ischaemia causes new blood vessels forming on the iris (rubeosis) - may block the drainage of aqueous fluid
- acceleration of age-related cataract formation
103
Pathogenesis
Eye in DM
microangiopathy in capillaries causes:
1. vascular occlusion causes ischaemia ± new vessel formation - potential to bleed
2. vascular leakage- pericytes lost, capillaries bulge- oedema and hard exudates--> flame shaped haemorrhages
104
Classification of eye disease in DM
Non-proliferative diabetic retinoapthy - mild, moderate or severe depending on degree of ischaemia
proliferative diabetic retinopathy- fine new vessles appear on the optic disc, retina and can cause vitreous haemorrhage
Maculopathy - leakage of vessels close to the macula causing oedema can can significantly threaten vision
105
Papilloedema
swelling of the optic disc caused by raised ICP
always bilateral, but not necessarily symmetrical
presentation- symptoms of raised ICP
106
Ramsay Hunt Syndrome
| herpes zoster oticus
herpes zoster infection of the facial nerve
often in the elderly, severe otalgia precedes VII CN palsy
zoster vesicles appear around the ear, in the deep meatus ± soft palate and tongue
Vertigo, tinnitus or deafness
Rx- aciclovir + prednisolone
107
Corneal abrasion
intense pain
local anaesthetic, stain with fluroescein
should start healing within 48hrs- re-examine after 24hrs
108
Eye burns
treat chemical burns promptly
instil anaesthetic drops every 2 mins until pt comfortable
bathe eye in copious clean water
late sequelae - corneal scarring, opacification and lid damage
109
Foreign bodies in the eye
cause- chemosis, subconjunctival bleeding, irregular pupils, iris prolapse, hypaema, vitreous haemorrhage, retinal tears
X-ray orbit, orbital USS
removal of superficial FBs may be remove dwtih a triangle of clean card- chloramphenicol drops after
