or branch retinal artery occlusion
Occlusion of the retinal artery may
be caused by arteriosclerotic changes, embolus
(from heart or carotid artery) or
Sudden painless visual loss which may
be complete (due to central retinal artery
occlusion) or partial (due to branch
retinal artery occlusion)
Patient usually have a history of hypertension
or heart disease
The visual acuity is reduced in central
retinal artery occlusion but may be normal
in branch retinal artery occlusion
Relative afferent pupillary defect is
present in central retinal artery occlusion
The retinal arteries are narrow or collapsed.
In central retinal artery occlusion,
the fovea shows a cherry-red spot against the
white infarcted retina.
In branch retinal artery occlusion,
the white infarcted retina corresponds to the
Emboli may be seen in the arteries if
the cause is emboli
Immediate referral if the visual loss
is less than 6 hours as treatment may restore
some or most of the function.
Treatment involves the use of intravenous
acetazolamide and globe massage to
lower the intraocular pressure and
hopefully re-establish the arterial flow.
Further management aim to uncover any
underlying diseases such as hypertension,
cardiac or carotid thrombus. An
ESR is usually performed in the absence of obvious
embolus to exclude arteritic causes.
Long term low dose aspirin is advised
to reduce the risk of occurrence.
Central retinal artery occlusion
showing the typical "cherry-red" spots again
the white infarcted retina. This
appearance is not permanent and usually
disappears after about three days
when the flow of the retina artery
is re-established but the retina
does not regain its function.
Branch retinal artery occlusion
in the infero-lateral retinal artery. The infarcted
retina appears as white.
Cholesterol emboli from the carotid
artery. This is the most common
cause of transient visual loss.
If the occlusion is prolonged, the retina
may become infarcted. Investigation
should include carotid doppler
and echocardiogram to search for
the source of the emboli.
to visual loss