what is dry macular degeneration characterised by?
• Dry macular degeneration: characterized by Drusen - yellow round spots in Bruch’s membrane
what is wet macular degeneration characterised by?
Wet (exudative, neovascular) macular degeneration: characterized by choroidal
neovascularisation. Leakage of serous fluid and blood can subsequently result in a rapid loss of vision. Carries worst prognosis
how is macular degeneration classified?
• Early age related macular degeneration (non-exudative, age related maculopathy): drusen and
alterations to the retinal pigment epithelium (RPE)
• Late age related macular degeneration (neovascularisation, exudative)
what are risk factors for macular degeneration?
what are features of macular degeneration?
what is included in the general management of macular degeneration?
• Stopping smoking
• High does of β-carotene, vitamins C and E, and zinc may
help to slow down visual loss for patients with established macular degeneration. Should avoid smoking due to an ↑ risk of lung cancer
what is the management of wet macular degeneration?
what are 5 causes of sudden painless loss of vision?
describe the clinical features of amaurosis fugax?
Amaurosis fugax: classically described as a transient monocular vision loss that appears as a “curtain coming down vertically into the field of vision in one eye”. Sometimes it occurs as episodes, caused by ipsilateral carotid artery diease.
Ischaemic optic neuropathy:
Central retinal vein occlusion:
Fundoscopy
• Widespread retinal haemorrhages in all 4 quadrants, which vary in appearance from a small-scattered retinal hemorrhages to marked confluent hemorrhages
• Marked dilated and tortuous retinal vessels
• Cotton-wool spots
• Optic disc edema, macular edema, and retinal
thickening
• Vitreous hemorrhages may be present
Central retinal artery occlusion:
Vitreous haemorrhage:
• Causes: diabetes, bleeding disorders
• Features may include sudden visual loss,
dark spots
• Large bleeds cause sudden visual loss
• Moderate bleeds may be described as numerous dark spots
• Small bleeds may cause floaters
what are the clinical features seen in posterior vitreous detachment?
what clinical features are seen in retinal detachment?
where is the lesion in a relative afferent pupillary defect?
Relative afferent pupillary defect: Also known as the Marcus-Gunn pupil, a relative afferent pupillary defect is found by the ‘swinging light test’. It is caused by a lesion anterior to the optic chiasm i.e. optic nerve or retina
what are two causes of RAPD?
Causes
• Retina: detachment
• Optic nerve: optic neuritis e.g. Multiple sclerosis
describe the afferent and efferent pathways of the pupillary light reflex
Pathway of pupillary light reflex
• Afferent: retina → optic nerve → lateral geniculate body → midbrain
• Efferent: edinger-westphal nucleus (midbrain) → oculomotor nerve
All cause what kind of pupil?
mydriasis: large pupil
what are drug causes of mydriasis?
Drug causes of mydriasis
• Topical mydriatics: tropicamide, atropine
• Sympathomimetic drugs: amphetamines
• Anticholinergic drugs: tricyclic antidepressants
who is holmes-adie pupil seen in? what kind of pupil is seen?
Holmes-ADIe pupil is a benign condition most commonly seen in women. It is one of the differentials of a DIlated pupil
Holmes-adie pupil:
• Unilateral in 80% of cases
• 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
The absence of which reflexes are associated with holmes adie pupil - called holmes adie syndrome?
Holmes-Adie syndrome
• Association of Holmes-Adie pupil with absent ankle/knee reflexes
what is angioid retinal streaks on fundoscopy?
Angioid retinal streaks are seen on fundoscopy as irregular dark red streaks radiating from
the optic nerve head. The elastic layer of Bruch’s membrane is characteristically thickened and calcified