Eye Problems in General Practice MR Besharati MD Shahid Sadoughi University
Topics to be discussed • Lacrimal disorders • Blepharitis • Degenerative changes of cornea and sclera • Age related maculopathy • Hypertensive eye disease • Cataract • Glaucoma • Diabetic eye disease
Lacrimal system • Stable tear film essential for maintenance corneal clarity • Nutritional and protective functions • Deficient tear film causes corneal and conjunctival damage
Tear film • Superficial lipid layer derived from meibomian glands • Aqueous tears derived from lacrimal gland contain immunoglobulins and lysozyme • Thin mucus layer created by goblet cells allow adherence aqueous tears to cornea • Tears flow from lacrimal gland to lacrimal puncta mainly along lower lid margin • Upper lid has essential function in applying mucus to corneal surface and ensuring even spread of tears
Lacrimal system – ‘dry eye’ • Keratoconjunctivitis sicca = aqueous tear deficiency • Common in elderly • Chronic gritty sensation, eyes not unduly red, stringy mucus, transient blurred vision • Associated with systemic disease eg RA • Associated with drugs – especially diuretics
Investigation of ‘dry eye’ • Tear film break up time (BUT) • Rose bengal staining • Schirmer’s test – absorbent paper strips placed in lower fornix, <10 mm wet in 5 minutes = deficiency
Treatment ‘dry eye’ • Artificial tear drops • Simple eye ointment at night (prolonged lubrication) • Acetylcysteine eye drops useful if filamentary keratitis • Treat associated blepharitis
Lacrimal disorders – ‘watering eye’ • Tears are produced by lacrimal glands • Flow along lid margins, spread by blinking • Enter upper and lower puncta to lacrimal sac • Flow down nasolacrimal duct to nose
‘watering eye’ • Excessive production of tears – can be paradoxical in dry eyes • Punctal malposition • Punctal stenosis • Blockage of lacrimal sac or nasolacrimal duct – syringing, -dacrocystorhinostomy
Blepharitis • Generalised eyelid inflammation • Staphylococcal or seborrheic dermatitis • Itchy red burning eyelid margins • Scales on lashes and crusty secretions on lids • Recurrent and may be associated with bacterial conjunctivitis
Blepharitis • Regular cleaning • Apply hot wet flannel firmly against closed eye • Use moistened cotton wool bud to wipe away secretions • Local antibiotic –chloramphenicol or fusidic acid • Add 1% hydrocortisone if persistent inflammation
Corneal degeneration • Arcus senilis occurs in 60% patients aged 50 and nearly all over 80 • Vogt’s white limbal girdle • Lipid keratopathy • Band keratopathy
Age-related macular degeneration • Leading cause of blindness in over 50s • Over ½ million people in UK affected by AMD • 190,000 new cases AMD in UK per year
What is AMD? • Degenerative condition of central retina • Dry AMD (85%) – atrophic form • Wet AMD responsible for 15% sufferers but 90% blindness – neovascular form with new abnormal vessels at the macula • High risk of second eye involvement within 5 years of first
AMD – risk factors • Age (wet AMD usually presents in patients over 50) • Genetics – hereditary link. Screening of blood relatives has debatable value • Race/gender – white females • Smoking increases wet and dry AMD • Hypertension • Post-menopausal women not on HRT more likely to develop neo-vascularisation
AREDS (Age Related Eye Disease Study) • Performed by National Eye Institute • Antioxidants including Vit A and Vit E • Zinc and copper • Beneficial in preventing progression to sight-threatening AMD
Dry AMD • 85% cases • Slow progression, not usually severe • Difficulty with reading and fine visual tasks • Distortion and metamorphosia uncommon • Drusen, pigmentation and atrophy of retina • No proven treatment • Low vision services helpful
Wet AMD • 15% cases • More severe, rapid visual loss, 3-6 months if untreated • Choroidal neovascularisation – abnormal vessels leak fluid into macula, causing retinal surface to become uneven with blurring and distortion of central vision • Scar tissue creates irreversible blind spots
AMD - symptoms • Recent change in visual function, in particular ability to read, recognise faces, difficulty with changing light conditions • On waking, dark patch in vision which quickly fades • Distortion of the shape of familiar objects especially kinking of lampposts/windows (and not double vision or ghosting associated with cataract)
AMD -Signs • Decreased acuity with Snellen chart • No improvement in acuity with pinhole (in macular disease) • Amsler grid testing • Fundoscopy – subretinal fluid, exudate, haemorrhage or pigment epithelial elevation
Rehabilitation • Provision and training in use of optical aids • Increase wattage of household bulbs • Mark cooker controls with tactile dots etc • Registration as blind or partially sighted in order to access local social support • Put in touch with community voluntary services or relevant support groups
Hypertensive eye disease • Severity of hypertension • degree of hypertensive vascular change • retinopathy • Duration of hypertension • degree of arteriosclerotic vascular change • retinopathy
Hypertensive features • Characterised by vasoconstriction and leakage • Diffuse arteriolar narrowing • Focal arteriolar narrowing • Severe hypertension may lead to obstruction of precapillary arterioles and cotton-wool spot formation
Hypertensive features • Abnormal vascular permeability leads to haemorrhages, retinal oedema and hard exudates • Deposition of hard exudates around the fovea may lead to their radial distribution as a macular star • Swelling of the nerve head occurs in malignant hypertension
Arteriosclerotic features • Thickening of vessel wall with hyaline degeneration and narrowing of the lumen • Arteriovenous crossing change / AV nipping • Copper wiring • Silver wiring – heightened reflex from opaque arterioles
Cataract • A common cause of visual loss • Most important cause of blindness worldwide • Lens opacification
Symptoms of cataract • Difficulty reading • Vision worsens in bright light (especially with central opacity) • Monocular diplopia • Haloes around lights • Improved near vision (nuclear sclerotic cataract can improve converging power of lens)
Signs of cataract • Reduction in acuity (unilateral/bilateral) • Diminished red reflex • Change in appearance of lens
Types of cataract • Senile • Traumatic • Metabolic • Toxic • Secondary • Hereditary
Treatment of cataract • No effective medical treatment • Decision to operate is a quality of life issue • Various surgical options
Chronic open angle glaucoma • Uncommon under age 40 • Major cause of blindness in the elderly • Asymptomatic • Gradual and painless visual loss • Central vision preserved until late in the disease progression
Signs of glaucoma • Raised intraocular pressure ( >21 mmHg) • Pathological cupping of optic disc – gradual loss of nerve fibres at disc resulting in a pale disc with an enlarged cup • Visual field loss
Causes of chronic open angle glaucoma • Impairment of aqueous outflow from the anterior chamber of the eye • Caused by alteration in function of trabecular meshwork overlying canal of Schlemm • Aetiology unknown- indirect ischaemic theory and direct mechanical theory • Familial tendancy
Medical treatment • Pilocarpine drops 1-4% – act via ciliary muscle to open drainage channels • Adrenaline drops 0.5-2% increase outflow aqueous humour • Timolol drops 0.25-0.5 % and other beta blockers reduce aqueous humour production • Acetozolamide capsules 250 mg reduce rate aqueous humour production
Laser / surgical options • Laser trabeculoplasty – laser burns to trabecular meshwork result in increased aqueous flow • Surgical drainage eg trabeculectomy – portion of sclera adjacent to the cornea is removed to create a fistula • Long –term monitoring with applanation tonometry (= pressure gauge) and perimetry(=field testing)
Diabetic eye disease • Background retinopathy • Maculopathy • Proliferative retinopathy
Diabetic background retinopathy • Blot haemorrhages • Hard exudates • Vision normal
Diabetic Maculopathy • Hard exudate at fovea • Vision irreversibly damaged
Diabetic proliferative retinopathy • New vessel formation at optic disc in response to ischaemia • Irreversible reduction in visual acuity • Risks of vitreous haemorrhage and retinal detachment
Goals for treatment • Good diabetic control can prevent new vessel formation • Concurrent diseases such as hypertension, renal disease, anaemia, hyperlipidaemia, can accelerate retinopathy and need to be treated • Pre-symptomatic screening and early photocoagulation
Screening for diabetic retinopathy • Allows laser photocoagulation to be used for maculopathy and proliferative retinopathy • May be done by regular eye examination • Increasing use of retinal photography • ?? Retinal photography in primary care
