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
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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
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Vision loss – Sudden (41%)
Gradual (28%)
Transient (15%)
Precipitated by exposure to bright lights (“bright light
amaurosis)
± Pain – Ocular / Orbital
 Incidental asymptomatic finding
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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
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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:
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Normal (23%)
Central scotomas (27%)
Nasal defects (23%)
Centrocaecal defects (5%)
Central or temporal islands (22%)
Carotid artery ultrasound
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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
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ERG
Diminished b- and a- waves
Management:
Ophthalmologist
 Physician/Neurologist
 Vascular surgeon
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Ocular treatment
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Anterior segment inflammation
Topical steroids and cycloplegics
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Ablation of retinal ischaemia
Early FFA, Only if retinal ischaemia >> 3000-5000 burns of
200-500μm spot size
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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
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Full medical and neurological assessment
Aspirin
Treatment of hypertension, diabetes
Stop smoking
Carotid Surgery
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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
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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