Eye in Systemic Diseases PDF

The Eye in Systemic Diseases Dr Nour Alnakshabandi MB.Ch.B CABO ICO 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 – Sy...

The Eye in Systemic Diseases Dr Nour Alnakshabandi MB.Ch.B CABO ICO 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: Basically any systemic disorder uEndocrine disorders uGastrointestinal uDisorders of disorders connective tissues uInfectious diseases uSkin diseases uCardiovascular & uInborn errors of Pulmonary diseases metabolism uHaemopoietic and lymphoreticular disorders uNeurological and muscular disorders Which common systemic disease is the highest cause of blindness in the working age population? Endocrine disorders: ÒMost important ones are : ÉDiabetes Mellitus ÉThyroid dysfunction ÉPituitary tumours Diabetes mellitus – Most common cause of blindness among 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: uVisual problems may occur due to: uDiabetic retinopathy uCataract uGlaucoma uIschaemic Optic Neuropathy uRetinal vein and artery occlusions uIIIrd, IVth and VIth nerve palsies Pathology of Diabetic Retinopathy – Hyperglycaemia causes- – Basement Membrane thickening – non-enzymatic glycosylation – increased free radical activity – increased flux through the polyol pathway – osmotic damage Processes of pathology ÒIschaemia ÉDirect effect on Rods and Cones ÉVEGF release causes new blood vessel formation which bleed and fibrosed ÉLeakage exudative process damages retinal layers Eye & Diabetes: uStages of Diabetic Retinopathy uBackground uPreproliferative uProliferative uMaculopathy Background / mild non proliferative DR Characterised Characterised by Mildby Mild Haems Haemorrhages / MAs: / Micro-aneurysms (MAs) no more severe than in this standard photo Preproliferative retinopathy Normal Venous beading, IRMA, and Severe/blot Haem. Intraretinal microvascular abnormalities Venous loops IRMA Proliferative diabetic retinopathy – New vessels grow on the disc (DNV), or elsewhere on the retinal surface (NVE) DNV even if it is around the disc but not more than one disc diameter Cotton Wool Spots = Soft exudates – 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 Can evolve very quickly Baseline 6 weeks later  Classification Non-proliferative – Mild – Moderate – Severe Proliferative – Mild-moderate – Severe – advanced Nonproliferative diabetic retinopathy – Mild : Indicated by the presence of at least 1 micro aneurysm. Referral : review in 1-2 years. Moderate: – Includes the presence of – hemorrhages, micro - aneurysms, and hard exudates Cotton wool spot. – Referral : – review in 6 months – 1 year ; or refer to ophthalmologist Severe: – The (4-2-1) rule; one or more of: – hemorrhages and microaneurysms in 4 quadrants. – venous beading in at least 2 quadrants. – intraretinal microvascular abnormalities in at least 1 quadrant – Referral : review in 4 months. Proliferative diabetic retinopathy – Neovascularization : NVE , NVD. – Vitreous / Preretinal hemorrhage. Fluorescein angiography Wide areas of capillary Normal vasculature dropout and ischaemia Proliferative retinopathy: New Vessels tend to bleed 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 New Vessels Can Also Grow on the Iris Rubeosis Iridis Neovascular Glaucoma  Treatment of Diabetic Retinopathy – Scattered laser pan retinal photocoagulation (PRP) for PDR Argon laser – Focal laser/laser grid for exudative maculopathy – Ischaemic Maculopathy NOT treatable – Anti VEGF  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 → Bitemporal hemianopia – Optic nerve dysfunction – Colour deficit – Visual deterioration – Optic atrophy – MRI scan + Neuro referral Thyroid eye disease (TED) Thyroid orbitopathy = thyroid ophthalmopathy A manifestation of Grave’s disease uPatient may be uEuthyroid TED preceding hyperthyroidism or after treatment of hyperthyroidism uHypothyroid When you over-treat hyperthyroidism. This can exacerbate TED (i.e TED is worse when the patient is hypothyroid) uHyperthyroid :-40% of patients with Graves disease get eye signs u4-8% loose vision – TED is the commonest cause of proptosis (unilateral or bilateral) in adults  Other features: ÒLid signs- lid lag, lid retraction ÒConjunctival hyperaemia and chemosis ÒKeratoconjunctivis Sicca ÒDysthyroid myopathy ÒOptic neuropathy  Management –Control thyroid status (medical/ surgical) –Lubricants –Orbital decompression surgery –Muscle surgery/ prism in glasses –Lid surgery Other endocrine disorders affecting eyes: Gland Disorder Ocular manifestations Hypothalamus Suprasellar Optic atrophy, tumours Papilloedema Parathyroids Hyper/ Hypo- Conjunctival & corneal parathyroidism calcification, cataract Adrenals Pheochromocytoma Hypertensive retinopathy Addison’s disease hyperpigmentation Cushing’s disease Cataract, exophthalmos Hypertensive retinopathy uDamage to the retina from high blood pressure uDuration increases risk uWorse with uDiabetes uhigh cholesterol usmoking uMalignant hypertension Symptoms of Hypertensive retinopathy uGrade 1- no symptoms uGrade 2/3- blurring of vision/headache/diplopia uGrade 4- Optic disc swelling gives blurred vision and field loss. uPatients often have poor renal function and are at risk of stroke and encephalopathy Ophthalmoscopy findings Hypertensive Retinopathy Signs of Hypertensive Retinopathy From focal closure of retinal microvasculature/microinfarcts – 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, AV Nicking e.g. nicking ± flame Haems. -Vessel sclerosis, threading 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 uAtrial fibrillation uAortic stenosis uHyperlipidaemia- arcus uHypercholesterolaemia u xanthalasma uThromboembolism: retinal arteriolar occlusions u Clot u Calcium u cholesterol Retinal Vein Occlusion – Second most common vascular disease causing loss of vision  Retinal Vein occlusion uPathophysiology uthrombus formation udisease of the vein wall uexternal compression of the vein u Retinalarteries and arterioles and their corresponding veins share a common adventitial sheath. uAtherosclerosis and thickening of the arteriole compresses the vein, eventually causing occlusion.  Venous occlusion Branch Retinal Vein Occl. Central Retinal Vein Occl. Etiology uAdvancing age - over 50% over 65 y u15% under the age of 45 uHypertension( 64% of patients) uHyperlipidaemia, diabetes, smoking and obesity. uRaised intraocular pressure. uInflammatory diseases - sarcoidosis, Behçet's syndrome. uHyperviscosity states- myeloma. uThrombophilic disorders (considered in