Retina 2

Professor K N Jha, MSKirtinath.jha@gmail.com

Learning Aims

• Hypertension and the Eye: Clinical features,

complications, relationship of retinal changes and

prognosis for life

• Retinal Vascular occlusions: Clinical features,

complications and treatment

Hypertension and the Eye • Retinopathy: FIPTs, microaneurysms, intraretinal

microvascular abnormalities (IRMAs), blot haemorrhages,

hard exudates, venous beading. and new retinal vessels

• Chroidopathy: Elschnig spots, Siegrist streaks

• Optic neuropathy: flame-shaped haemorrhages,

blurring of the disc margins, florid disc edema with

secondary retinal venous stasis, and macular exudates

• Hypertension is also associated with

-Intraretinal haemorrhages

- Branch retinal artery

occlusion(BRAO)

- Branch retinal vein occlusion(BRVO)

-Central retinal vein occlusion(CRVO)

-Retinal arterial macroaneurysms

Focal Intraretinal Periarteriolar Transudate

Elschnig spots

Hypertensive Optic Neuropathy

Hypertensive retinal change: Classification

Grade I : Arteriolar narrowing

Grade II: Arteriovenous crossing changes

Grade III: Hemorrhage and exudates along with the

changes in grade I and II plus

Grade IV: Hemorrhages, exudates, and papilloedema

Retinal vascular occlusionArterial OcclusionVenous Occlusion

Arterial Occlusive Disease

• Branch Retinal Artery Occlusion(BRAO)

• Central Retinal Artery Occlusion(CRAO)

Arterial Occlusive Disease

Fundamentals:

• Retinal ischemia results from occlusion of

common carotid artery to intraretinal arteries

Precapillary Retinal Arterial Obstruction

• Leads to NFL infarct(CWS/soft exudates)

• They are ¼ dd in size or smaller

• Fade in 5-7 weeks

• Effect on Va or field will depend on location

and size

Etiology: BRAO/CRAO

Embolus/thrombosis :from carotids /heart-Cholesterol emboli -Platelet-fibrin thrombus-Calcific emboli-Infective endocarditis, fat emboli etc.

In addition in CRAO:-Hemorrhage under plaque-Spasm-Dissecting aneurysm

Other rare causes

• Migraine• Trauma• Coagulation disorders• Sickle cell disease• MVP• Oral contraceptive• Toxoplasma/syphilitic retinochoroiditis

Symptoms and signs

BRAO

• Initially may remain clinically silent

• Later: Edematous opacification of retina

• Permanent field defect

Management:BRAO

• Determine systemic etiology

• No ocular therapy

• Massage of the globe may be tried

Central Retinal Artery Occlusion

• Clinical presentation:Sudden, severe, painless loss of vision Ophthalmoscopic feature:-Retina :edematous and opaque-Foveola: Cherry-red spot-Cholesterol emboli at retinal arterial bifurcation -Arterioles and venules are markedly narrowed-Cattle-truck appearance- Pupil:-RAPD

Central Retinal Artery Occlusion

• About 2/3rd of patients have Va of < 3/60 and

visual prognosis is poor.

• If cilioretinal artery is present central vision may

be preserved.

• Leading cause of death in these cases is

cardiovascular disease.

Investigations

-Same as BRAO

-Look for evidences of giant cell arteritis

-Blood for ESR and C-reactive protein

Management• To be started without delay• They include:

• Reduction of IOP by ocular massage

• Ant chamber paracentesis

• Retrobulbar anaesthesia

• Inhalation of 95% O2+ 5% CO2 mixture

• Oral acetazolamide and aspirin

• Corticosteroid therapy to save the other eye, if giant cell arteritis is

diagnosed

Venous Occlusive Disease

• Branch Retinal Vein Occlusion(BRVO)

• Central Retinal Vein Occlusion(CRVO)

Retinal venous occlusion

• Predisposing conditionsSystemic-Hypertension-Arteriosclerosis-Cardiovascular diseaseOcular-History of glaucoma

Retinal venous occlusion

• In young people

-Infective periphlebitis

-Facial erysipelas

-Orbital cellulitis

Pathology

• Common adventitia

• Thickening of the arterial wall

• Turbulence in blood flow, endothelial damage

• Thrombotic occlusion

Pathophysiology of venous occlusion

Venous Occlusion

Stagnation

Increased extravascularpressure

Hypoxia

Oedema andhaemorrhage

Sec art narrowing

Symptoms

BRVO

Depends on whether central vision (macula) is

involved or not

Branch Retinal Venous Occlusion

BRVO:Visual Prognosis

Depends on

• Capillary damage and macular ischemia

• Macular edema

• Retinal neovascularisation 40 %.

• 50-60 % will maintain 6/12 after 1yr.

• Secondary glaucoma, rarely.

Management

• FFA• BRVO study• Photocoagulation

Focal for macular edemaPRP for retinal neovascularisation

CRVO:Types

• Non-ischemic

• Ischemic (diagnosis by FFA)

• Papillophlebitis (combined inflammatory and

occlusive mechanism)

CRVO

Clinical features: Symptoms: transient blurring of vision

Ophthalmoscopic Features

• Dilatation and tortuosity of affected vein

• Superficial hemorrhages

• Retinal edema

• Cotton wool spots(soft exudates)

• Macular edema in case of macular involvement

• Fluorescein fundus angiography

Vascular sheathing and collaterals Hard exudates

Evaluation

Visual acuity and RAPD

IOP

Gonioscopy

Look for iris neovascularisation

FFA to determine whether the condition is ischemic or no-

ischemic

Exclude carotid occlusive disease

Management

• CRVO study

• Associated medical condition

• Glaucoma

• Panretinal photocoagulation for iris

vascularization

Hyperviscosity retinopathy

• Generally bilateral

• They are related to disproteinemias e.g.

Waldenstrom macroglobulinemia or,multiple

myeloma

Macular edema

• Laser photocoagulation :No benefitmay benefit in young in improving VaCorticosteroid and aspirin:efficacy is

unprovenSystemic anticoagulation: not

recommendedIntravitreal triamcinolone acetonide

Iris neovascularisation

• Predictive factor:Poor visual acuity• Risk factors:Retinal non-perfusion ,intraretinal

blood• Panretinal photocoagulation when iris

neovascularisation occurs• Prophylactic Panretinal photocoagulation if

close follow-up of patient is not possible

BRVO:Visual Prognosis

Depends on • Extent of capillary damage and macular

ischemia• Integrity of parafoveal capillaries• Macular edema, retinal

hemorrhage,parafoveal retinal capillary occlusion

• Retinal neovascularisation

Management

• Photocoagulation

• Pars plana vitrectomy

• Intravitreal trimcinolone

Photocoagulation

• Indications:

-Chronic macular edema with intact perifoveal

retinal capillary perfusion

-Posterior segment neovascularisation

-Iris neovascularisation

Photocoagulation

• Visual acuity 6/12 to 6/60

• Argon Laser grid pattern photocoagulation is

applied in areas of capillary leakage identified

by FFA

Panretinal photocoagulation

• For areas of retinal capillary non-perfusion

• Disc neovascularisation

Peripheral retinal cryoablation

• In those cases where hazy media due to

vitreous haemorrhage do not permit

photocoagulation

Vitrectomy and/or RD Surgery

• For non-resolving vitreous hemorrhage

• Retinal detachment

Points To Remember• Retinal Vascular Occlusions cause sudden painless

diminution of vision.

• Arterial occlusions result from atheromatous plaque,

emboli, or vasculitis.

• Venous occlusions in elderly result from arteriosclerosis

• Macular ischemia/edema, vitreous hemorrhage or

neovascularisation result in visual loss.

Points To Remember

• Visual loss in arterial occlusion is irreversible.

• Macular edema is treated with laser,

intravitreal steroid/ anti-VEGF agents.

• Prognosis of Venous occlusions depend upon

the clinical features and the course.