Ocular Ischaemic Syndrome Dr Gulrez Ansari Department of Ophthalmology Watford General Hospital 3 rd 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: 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 >> burns of μm 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