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The Eye in Systemic Diseases. Department of Ophthalmology University Hospitals of Coventry and Warwickshire 2013. Learning objectives. Understand which systems may have eye related problems How the eye problems may herald systemic disease
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The Eye in Systemic Diseases Department of Ophthalmology University Hospitals of Coventry and Warwickshire 2013
Learning objectives • Understand which systems may have eye related problems • How the eye problems may herald systemic disease • Understand some of the mechanisms of systemic disease and the eye.
Eye- a unique organ • Systemic diseases affect eyes in various ways BUT ALSO • Many of the systemic diseases may be diagnosed first by ophthalmologist
Eyes can be affected in: • Endocrine disorders • Disorders of connective tissues • Skin diseases • Inborn errors of metabolism • Gastrointestinal disorders • Infectious diseases • Cardiovascular & Pulmonary diseases • Haemopoietic and lymphoreticular disorders • Neurological and muscular disorders
Which common systemic disease is the highest cause of blindness in the working age population?
Endocrine disorders: • Most important ones are : • Diabetes Mellitus • Thyroid dysfunction • Pituitary tumours
Diabetes mellitus • Most common cause of blindness amongst individuals of working-age ( 20-65 years). • The prevalence of blindness due to DR in Western Communities is estimated as between 1.6-1.9/ 100,000
Eye & Diabetes: • Visual loss may occur through • Diabetic retinopathy • Cataract • Glaucoma • Ischaemic Optic Neuropathy • Retinal vein and artery occlusions • IIIrd, IVth and VIth nerve palsies
Eye & Diabetes: • Stages of Diabetic Retinopathy • Background • Preproliferative • Proliferative • Maculopathy
Pathology of Diabetic Retinopathy • Hyperglycaemia causes- • Basement Membrane thickening • non-enzymatic glycosylation • increased free radical activity • increased flux through the polyol pathway • osmotic damage
Microscopic Anatomical Changes Microanerysms • Pericytes which surround the retinal capillaries are damaged • Damage to endothelial cells leads to dilated capillaries and venules • These altered vessels allow serum and blood to leak into the retina
Processes of pathology • Ischaemia • Direct effect on Rods and Cones • VEGF release causes new blood vessel formation which bleed and fibrose • Leakage exudative process damages retinal layers
Fluorescein angiography Normal vasculature Wide areas of capillary dropout and ischaemia
Characterised by Mild Haems / MAs:no more severe than in this standard photo Background / mild non proliferative DR
Normal Preproliferative retinopathy Venous beading, IRMA, and Severe/blotch Haem. IRMA Venous loops
Cotton Wool Spots • Microinfarcts of nerve fiber layer • Often associated with other preprolif. DR signs • If isolated CWS (no other preprolif DR) may be caused by HTN or recent BS tighter control
Proliferative diabetic retinopathy • New vessels grow on the disc (DNV), or elsewhere on the retinal surface (NVE)
Proliferative diabetic retinopathy Can evolve very quickly Baseline 6 weeks later
New Vessels Can Also Grow on the Iris • Rubeosis Iridis • Neovascular Glaucoma
Late Complications of Proliferative DR Tractional Retinal Detachment
Diabetic maculopathy Exudative • Exudates:intraretinal accumulations of lipids leaking from abnormal retinal capillaries and microaneuryisms, may form a circinnate pattern • Leakage of fluid that distorts the retinal architecture Exudative Maculopathy Normal Macula
Diabetic maculopathy Ischaemic + Mixed exudative/ischaemic Ischaemia Normal capillary bed
Treatment of Diabetic Retinopathy • Scattered laser pan retinal photocoagulation (PRP) for PDR • Focal laser/laser grid for exudative maculopathy • Ischaemic Maculopathy NOT treatable
Appearance of fresh laser burns Atrophic, old laser scars Panretinal laser photocoagulation (PRP) for proliferative DR
Systemic Risk Factors and DR • Blood sugar and BP control are as good as laser treatment for reducing the risk of retinopathy progression and loss of vision • Nephropathy is a risk factor for DR
Hyperlipidaemia and diabetic maculopathy • There is evidence that diabetics who have exudative maculopathy with extensive lipid exudates benefit from active treatment of hyperlipidaemia
Endocrine disorders and the eye • Thyroid • Pituitary • Hypothalamus • Parathyroid • Adrenals
Pituitary tumours • Headache • Visual field defect • Optic nerve dysfunction • Colour deficit • Visual deterioration • Optic atrophy • MRI scan + Neuro referral
Thyroid eye disease (TED) • Patient may be • Euthyroid • Hypothyroid • Hyperthyroid :-40% of patients with Graves disease get eye signs • 4-8% loose vision
TED is the commonest cause of proptosis (unilateral or bilateral) in adults
Other features: • Lid signs- lid lag, lid retraction • Conjunctival hyperaemia and chemosis • Keratoconjunctivis Sicca • Dysthyroid myopathy • Optic neuropathy
Management • Control thyroid status (medical/ surgical) • Lubricants • Orbital decompression surgery • Muscle surgery/ prism in glasses • Lid surgery
Hypertensive retinopathy • Damage to the retina from high blood pressure • Duration increases risk • Worse with • Diabetes • high cholesterol • smoking • Malignant hypertension
Symptoms of Hypertensive retinopathy • Grade 1- no symptoms • Grade 2/3- blurring of vision/headache/diplopia • Grade 4- Optic nerve swelling gives blurred vision and field loss. • Patients often have poor renal function and are at risk of stroke and encephalopathy
From focal closure of retinal microvasculature/microinfarcts Signs of Hypertensive Retinopathy • CWS (Diast BP often >100mmHg) • Flame shaped Haem. CWS + AV Nicking
Arteriolosclerosis often coexist: • -Arteriolar narrowing, focal or diffuse • -Arteriolar colour changes • -AV crossing changes, • e.g. nicking ± flame Haems. • -Vessel sclerosis, threading AV Nicking
Hypertensive Retinopathy, Severe • Rarely retinal/macular oedema • Disc oedema + severe macular oedema with macular star in extreme cases (malignant HTN, with BP on the range of 250/150mmHg) • Macular star may develop in weeks & resolve in months • Disc oedema may develop in days and resolve in weeks or months
Treatment • Lower blood pressure to below 140/90mmHg
Malignant hypertension • Collagen vascular diseases • Renal problems • Eclampsia of Pregnancy • Pheochromocytoma
Cardiovascular Diseases causing eye problems • Atrial fibrillation • Aortic stenosis • Hyperlipidaemia- arcus • Hypercholesterolaemia • xanthalasma • Thromboembolism: retinal arteriolar occlusions • Clot • Calcium • cholesterol
Retinal Vein Occlusion • Second most common vascular disease causing loss of vision
Retinal Vein occlusion • Pathophysiology • thrombus formation • disease of the vein wall • external compression of the vein • Retinal arteries and arterioles and their corresponding veins share a common adventitial sheath. • Atherosclerosis and thickening of the arteriole compresses the vein, eventually causing occlusion.
Branch Retinal Vein Occl. Central Retinal Vein Occl. Venous occlusion
Etiology • Advancing age - over 50% over 65 yo • 15% under the age of 45 • Hypertension( 64% of patients) • Hyperlipidaemia, diabetes, smoking and obesity. • Raised intraocular pressure. • Inflammatory diseases - sarcoidosis, Behçet's syndrome. • Hyperviscosity states- myeloma. • Thrombophilic disorders (considered in <45 yo • hyperhomocysteinaemia • lupus anticoagulant, • anticardiolipin antibodies; or inherited disorders such as factor V Leiden, protein C or S deficiencies.[3]
Connective tissue disorders Marfan’s syndrome: Tall stature Large eyes Myopia Ectopialentis 2°glaucoma, retinal detachment
Connective tissue disorders • Ehlers-Danlos syndrome: • Blue sclera, • keratoconus, • ectopia lentis, • angioid streaks