passmed Flashcards
what is holmes-adie pupil
dilated pupil
once the pupil has constricted it remains small for an abnormally long time
slowly reactive to accommodation but very poorly (if at all) to light
Holmes-Adie syndrome
association of Holmes-Adie pupil with absent ankle/knee reflexes
commonly seen in women
what is Herpes zoster ophthalmicus (HZO
reactivation of the varicella-zoster virus in the area supplied by the ophthalmic division of the trigeminal nerve
features of herpes zoster opthalmicus
vesicular rash around the eye, which may or may not involve the actual eye itself
Hutchinson’s sign: rash on the tip or side of the nose. Indicates nasociliary involvement and is a strong risk factor for ocular involvement
management of hZO
oral antiviral treatment for 7-10 days
ideally started within 72 hours
intravenous antivirals may be given for very severe infection or if the patient is immunocompromised
topical antiviral treatment is not given in HZO
topical corticosteroids may be used to treat any secondary inflammation of the eye
ocular involvement requires urgent ophthalmology review
Complications of HZO
ocular: conjunctivitis, keratitis, episcleritis, anterior uveitis
ptosis
post-herpetic neuralgia
entropion?
inturning of the eyelids
ectropion?
out-turning of the eyelids
types of stye
external (hordeolum externum): infection (usually staphylococcal) of the glands of Zeis (sebum producing) or glands of Moll (sweat glands).
internal (hordeolum internum): infection of the Meibomian glands. May leave a residual chalazion (Meibomian cyst)
causes of adie pupil
damage to parasympathetic innervation of the eye due to viral or bacterial infection.
marcus-gunn pupil
Relative afferent pupillary defect, seen during the swinging light examination of pupil response. The pupils constrict less and therefore appear to dilate when a light is swung from unaffected to affected eye.
causes for marcus-gunn pupil
damage to the optic nerve or severe retinal disease
horners syndrome
Miosis (pupillary constriction), ptosis (droopy eyelid), apparent enophthalmos (inset eyeball), with or without anhidrosis (decreased sweating) occurring on one side
cause of horner
damage to the sympathetic trunk on the same side as the symptoms, due to trauma, compression, infection, ischaemia or many others.
hutchinson’s pupil?
Unilaterally dilated pupil which is unresponsive to light
cause of huthcinsons pupil
A result of compression of the occulomotor nerve of the same side, by an intracranial mass (e.g. tumour, haematoma)
argyll-robertson pupil
Bilaterally small pupils that accommodate but don’t react to bright light.
causes of argyll-robertson pupil
diabetes mellitus
syphillis
contradictions to lumbar puncture
papilloedema
focal neurology such as a cranial nerve III or VI palsy can indicate increased intracranial pressure due to a cerebral mass.
CSF findings of a
MS
subarachnoid haemorrhage
MS - oligoclonal bands
subarachnoid haemorrhage - RBCs
what is papilloedema
optic disc swelling that is caused by increased intracranial pressure. It is almost always bilateral.
features of pailloedema on fundoscopy
- 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
causes of papilloedema
- space-occupying lesion: neoplastic, vascular
- malignant hypertension
- idiopathic intracranial - hypertension
- hydrocephalus
- hypercapnia
Rare causes include
hypoparathyroidism and hypocalcaemia
vitamin A toxicity
causes of tonic or Adie’s pupil
Caused by damage to parasympathetic fibres innervating the pupil constrictor muscle with cell bodies in the ciliary ganglion
Likely cause an unrecognised viral infection
acetozolamide
acute angle glaucoma
chloramphenicol
bacterial conjunctivitis
causes of mydriasis
third nerve palsy Holmes-Adie pupil traumatic iridoplegia phaeochromocytoma congenital
Drug causes of mydriasis
topical mydriatics: tropicamide, atropine
sympathomimetic drugs: amphetamines, cocaine
anticholinergic drugs: tricyclic antidepressants
causes of RAPD
optic nerve disorders - MS -optic neuritis - optic nerve tumors - trauma -glaucoma - viral infections - granulomatosis before optic chiasm retina - retinal detachment
Tx of RAPD
observe
gets better in a few months
retinal detachment
fluid in RPE and sensiry retina
Tx tear in retina but no fluid separating it out
laser or cryotherapy
types of retinal detachment
rhegmatogenous - witha tear U shaped retina, macula on, degenerative changes in neurosensory retina creating a hole allowing to fluid to pass from the virteous to the subretinal space between sensory retina and RPE - trauma
exudative - fluid build up in subretinal space due to breakdown of blood- retinal barrier
HTN, vasculitis, AMD, tumor
tractional retinal detachement - pulling, common miopic
presentation of retinal detachment
preceded by
Floaters
flashes
peripheral field loss initially -> A veil or curtain over the field of vision
loss of red reflex
loss of central vision at a later stage
detached retina appears grey on fundoscopy
Straight lines appear curved
Central visual loss
Field loss - sudden painless curtain like loss of peripheral visual loss
fall in acuity
other causes of retinal detachment
proliferative diabetic retinopathy
uveitis
intraocular tumours
prognosis of retinal detachment
time to give definitive treatment
site and extent of detachment
nature of underlying pathology
DD for retinal detachment
migraine
retinal artery occlusion
post vitreous detachment
vitreous haemorrhages - diabetes
Mx of retinal detachment
superior tear - lie them flat
inferior tear - 30 degrees
2) surgery - vitreoctomy -> to remove traction of the vitreous, cryotherapy/laser photocoagulation stick retina back on
causes of tunnel vision
papilloedema glaucoma retinitis pigmentosa choroidoretinitis optic atrophy secondary to tabes dorsalis hysteria
causes of painless loss of vision
- optic neuritis
- retinal detachment
- posterior vitreous detachment
- vitreous haemorrhage
- retinal migraine
- CRA occlusion
- CRV occlusion
define transient monocular visual loss
sudden, transient loss of vision that lasts less than 24 hours.
differentials for amaurosis fugax
- large artery disease (atherothrombosis, embolus, dissection),
- small artery occlusive disease (anterior ischemic optic neuropathy, vasculitis e.g. temporal arteritis),
venous disease and hypoperfusion
causes of central retinal vein occlusion
glaucoma, polycythaemia, hypertension
fundoscopy finding of CRVO
severe retinal haemorrhages
chees pizza appearance
causes of vitreous haemorrhage
proliferative diabetic retinopathy (over 50%)
posterior vitreous detachment
ocular trauma: the most common cause in children and young adults
, bleeding disorders, anticoagulants
features of vitreous haemorrhage
sudden visual loss
dark spots
features of posterior vitreous detachment
Flashes of light (photopsia) - in the peripheral field of vision
Floaters, often on the temporal side of the central vision
features of vitreous haemorrhage
painless visual loss or haze (commonest)
red hue in the vision
floaters or shadows/dark spots in the vision
Large bleeds cause sudden visual loss
Moderate bleeds may be described as numerous dark spots
Small bleeds may cause floaters
signs of vitreous haemorrhage
decreased visual acuity: variable depending on the location, size and degree of vitreous haemorrhage
visual field defect if severe haemorrhage
Ix for vitreous haemorrhage
- dilated fundoscopy: may show haemorrhage in the vitreous cavity
- slit-lamp examination: red blood cells in the anterior vitreous
- ultrasound: useful to rule out retinal tear/detachment and if haemorrhage obscures the retina
- fluorescein angiography: to identify neovascularization
- orbital CT: used if open globe injury
what is post vitreous detachment
separation of the vitreous membrane from the retina
risk factors of post vitreous detachment
As people age, the vitreous fluid in the eye becomes less viscous, and thus, does not hold its shape as well. Therefore, it pulls the vitreous membrane away from the retina towards the centre of the eye.
Highly myopic (near-sighted) patients are also at increased risk of developing posterior vitreous detachment earlier in life. This is because the myopic eye has a longer axial length than an emmetropic eye.
symptoms of post vitreous detachment
The sudden appearance of floaters (occasionally a ring of floaters temporal to central vision)
Flashes of light in vision
Blurred vision
Cobweb across vision
The appearance of a dark curtain descending down vision (means that there is also retinal detachment)
signs of post vitreous detachment
Weiss ring on ophthalmoscopy (the detachment of the vitreous membrane around the optic nerve to form a ring-shaped floater).
Ix for post vitreous detachment
All patients with suspected vitreous detachment should be examined by an ophthalmologist within 24hours to rule out retinal tears or detachment.
Mx for post vitreous detachment
Posterior vitreous detachment alone does not cause any permanent loss of vision. Symptoms gradually improve over a period of around 6 months and therefore no treatment is necessary.
If there is an associated retinal tear or detachment the patient will require surgery to fix this.
features of horners
miosis (small pupil)
ptosis
enophthalmos* (sunken eye)
anhidrosis (loss of sweating one side)
what is retinitis pigmentosa
affects the peripheral retina resulting in tunnel vision
features of retinitis pigmentosa
night blindness is often the initial sign
tunnel vision due to loss of the peripheral retina (occasionally referred to as funnel vision)
fundoscopy finding of retinitis pigmentosa
black bone spicule-shaped pigmentation in the peripheral retina, mottling of the retinal pigment epithelium
ass diseases of retinitis pigmentosa
Refsum disease: cerebellar ataxia, peripheral neuropathy, deafness, ichthyosis Usher syndrome abetalipoproteinemia Lawrence-Moon-Biedl syndrome Kearns-Sayre syndrome Alport's syndrome
define anisocoria
different pupil size
anisocoria worse in the light
parasympahteitc issue
ciliary ganglion
