Ocular Ischaemic Syndrome - eye-laser
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Transcript Ocular Ischaemic Syndrome - eye-laser
Ocular Ischaemic
Syndrome
Dr Gulrez Ansari
Department of Ophthalmology
Watford General Hospital
3rd November 2004
Ocular Ischaemic Syndrome
A severe form of chronic ischaemia of both
anterior and posterior segments of the eye as
well as other orbital structures supplied by the
ophthalmic artery.
Chronic hypoperfusion when carotid artery
stenosis > 90%
Usually unilateral
Age: 50-80 yrs
Male:Female::2:1
Symptoms
Vision loss – Sudden (41%)
Gradual (28%)
Transient (15%)
Precipitated by exposure to bright lights (“bright light
amaurosis)
± Pain – Ocular / Orbital
Incidental asymptomatic finding
Signs
Anterior Segment
Dilated Episcleral vessels
Corneal edema
AC Cells
Flare (“ischemic pseudoinflammatory uveitis”)
Mid-dilated poorly reactive pupil
Cataract
Iris atrophy
Iris neovascularisation ± angle neovascularisation
Neovasuclar Glaucoma
Gonioscopy – Angle neovascularisation
Signs
Posterior Segment
Disc – NVD, Easily inducible retinal artery pulsation,
AION (rare)
Vessels – Venous dilatation (no tortuosity)
Periphery – Mid peripheral haemorrhages,
Microaneurysms
Macular oedema
Ischaemic changes – Retinal arteriolar narrowing, retinal
capillary non-perfusion
Retinal Haemorrhages:
Differential Diagnosis:
Other causes of iris neovascularisation:
Proliferative diabetic retinopathy
Ischaemic CRVO
Systemic evaluation:
Systemic associations:
Diabetes mellitus (56%)
Hypertension (50-73%)
Ischaemic heart disease (38-48%)
Cerebrovascular disease (27-31%)
Giant cell arteritis (rare)
Investigations:
FFA
Aid in confirmation of diagnosis,
Demonstrate retinal capillary non-perfusion – to validate
PRP
Delayed & patchy choroidal filling
ed retinal arteriovenous circulation times
Areas of retinal capillary non-perfusion
Late leakage from arterioles and veins
Macular oedema
FFA
Visual Fields:
Normal (23%)
Central scotomas (27%)
Nasal defects (23%)
Centrocaecal defects (5%)
Central or temporal islands (22%)
Carotid artery ultrasound
Carotid occlusion, usually 90% or more
Colour Doppler Imaging (CDI) of retrobulbar circulation
Reduced peak systolic velocities in ophthalmic & central
retinal arteries
Conitnuous / intermittent reversal of ophthalmic artery blood
flow
Limitation: Difficult to reliably reproduce orbital blood flow
measurements
ERG
Diminished b- and a- waves
Management:
Ophthalmologist
Physician/Neurologist
Vascular surgeon
Ocular treatment
Anterior segment inflammation
Topical steroids and cycloplegics
Ablation of retinal ischaemia
Early FFA, Only if retinal ischaemia >> 3000-5000 burns of
200-500μm spot size
Control of IOP & Neovascular glaucoma
Medical therapy (topical β blockers, cycloplegics, oral
carbonic anhydrase inhibitors)
Surgery (trab with mitomycin C, Tube shunt procedure)
Ciliary body ablation (cyclocryotherapy, laser
cyclophotocoagulation – Nd:YAG / Diode laser)
Medical Treatment
Full medical and neurological assessment
Aspirin
Treatment of hypertension, diabetes
Stop smoking
Carotid Surgery
Of benefit in symptomatic Cerebral ischaemia
when there is >70% carotid artery stenosis
Pts with severe carotid stenosis and a recent
cerebral rather than ocular event had a greater
risk of stroke when taking medical treatment &
therefore a greater benefit from surgery
Impact on visual prognosis unclear (no
randomized controlled studies)
In one series – 7% improved Vn, 33% no change, 60%
worsened
Conclusion
Rare, but severe condition
Leads to significant visual loss and chronic
ocular pain
Iris neovascularisation is an indicator of poor
visual prognosis
5 year mortality rate 40%
Majority of deaths are due to cardiac disease