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Diseases of the Lens Prof.Dr.Raciha Beril Küçümen Yeditepe University Department of Ophthalmology 2016 - 2017 Educational Year AIM • Learning the diagnosis and treatment of lens diseases. • Learning the relationship between lens diseases and other systemic diseases. OBJECTIVE • To be able to completely list the etiology, classification, signs and symptoms, and different types of cataract. • To be able to completely write the diseases and syndromes that cause lens dislocation. • To be able to completely list lens shape disorders. • To be able to completely list of cataract surgical techniques and technology used in modern cataract surgery. Cataract • Greek “katarraktes” : Waterfall / Şelale Cataract • Any congenital or acquired opacity in the lens capsule or substance is called cataract. Classification of cataract • Aetiological • Morphological • According to maturity • According to age of onset Aetiological • • • • • • • • • • Senile Presenile Traumatic Metabolic Toxic Complicated (secondary) Maternal infection Maternal drug ingestion Syndromes Hereditary Cataract • Age - related cataract is a very common cause of visual impairment in older adults. • In cross - sectional studies the prevalence of cataract is 50% in people between the ages of 65 and 74 increasing to 70% in those over the age of 75. • The pathogenesis of age - related cataract is multifactorial and not completely understood. • Smoking, ultraviolet radiation Senile • Subcapsular: Anterior or posterior.Patients with posterior subcapsuler cataract have more diminished near vision than their distance vision. • Nuclear: Its frequently associated with myopia due to an increase in the refractive index of the lens and also with increased spherical aberration. Some individuals read without spectacles a condion referred as second sight • Cortical: Anterior, posterior, equatorial. • Christmas Tree cataract is uncommon , characterized by polychromatic, needle-like deposits in cortex and nucleus - myotonic dystrophy Subcapsular cataract Anterior Posterior Nuclear cataract Progression • Exaggeration of normal nuclear ageing change • Increasing nuclear opacification • Causes increasing myopia • Initially yellow then brown Cortical cataract Progression Initially vacuoles and clefts Progressive radial spoke-like opacities Christmas Tree Cataract Traumatic: • Penetrating • Metallosis bulbi: intraocular foreign body, siderosis =iron, chalcosis = copper, Electroretinogram ERG is pathologic • Concussion • Infrared irradiation (glass-blowers’ cataract) • Electrical injury • Chemical injuries • Ionizing radiation (ocular tumors such as retinoblastoma) • Ultraviolet radiation Trauma is the most common cause of unilateral cataract in young individuals. Causes of traumatic cataract Concussion ‘Vossius’ ring from imprinting of iris pigment Flower-shaped Penetration Other causes • Ionizing radiation • Electric shock • Lightning Metabolic: • Diabetes:Is associated with two types of cataract. • 1)Senile cataract which appears earlier and may progress more rapidly. • 2)True diabetic cataract which is due to osmotic overhydration of the lens and appears as bilateral white punctate or snowflake posterior or anterior opacities. Other causes of cataract - diabetes Juvenile • • Adult • Metabolic: • Galactosaemia – Oil droplet cataract Absence of galactose-1-phosphate uridyl transferase . Failure to thrive, psychomotor retardation, jaundice, diarrhoea, vomiting, renal disease and hepatosplenomegaly. • • • • • • • • Hypoglycaemia Galactokinase deficiency Mannosidosis Fabry’s disease - angiokeratoma corporis diffusum Lowe syndrome – Posterior lenticonus Wilson disease – Sunflower cataract Hypocalcaemia- tetanic cataract-parathyroid destruction Myotonic dystrophy – ‘Christmas tree’ cataract Toxic: • • • • • • Corticosteroids Chlorpromazine- (Largactil) sedative Miotics Busulphan - Myleran Gold – Romatoid arthritis Amiodarone Corticosteroids: • • • • Posterior subcapsular cataract Safe dose? Children are more susceptible Individual susceptibility (genetic?) Less in intermittent therapy Drugs Systemic or topical steroids - initially posterior subcapsular Chlorpromazine - central, anterior capsular granules Other drugs Long-acting miotics • Amiodarone • Busulphan • Secondary: • Anterior uveitis: This is the most common cause of secondary cataract.The lens opacification seems to progress more rapidly in the presence of posterior synechia. • Hereditary retinal: Retinitis pigmentosa, Leber’s congenital amaurosis,Wagner’s and Stickler’s syndrome) • High myopia • Glaukomflecken – acute angle closure glaucoma Glaucoma and Cataract • Glaukomflecken Acute angle closure glaucoma • Cataract and Glaucoma Lens – Induced Glaucoma Phacolytic Glaucoma mature /hypermature cataracts: denatured lens protein leaks through intact capsule, macrophages ingest lens protein , together they clog the trabecular meshwork. Lens Particle Glaucoma After cataract surgery retained cortical material particles obstruct trabecular meshwork Phacomorphic Glaucoma Intumescent cataract causes pupillary block and angle closure glaucoma Lens – Induced Glaucoma Signs & Symptoms: • • • • • • • • • • Headache Nausea Impaired general condition Red eye Pain in the eye Visual loss High intraocular pressure Middilated pupil with no reaction Shallow anterior chamber Leukocoria Treatment: • Systemic & Topical antiglaucomatous agents • Tranquilizers • Laser iridotomy • Cataract Surgery Congenital Cataract Maternal infections: • Rubella: Fetal infection is the direct result of maternal viraemia (which may be clinical or subclinical) with seeding of the virus in the plasenta. • Fetal infection is about 50% during the first 8 weeks,33% between week 9 and 12 and about 10% between 13 and 24. • Cataract, microphtalmos,retinopathy, glaucoma etc • Cataracts are present in about 50% of cases.After the gestastional age of 6 weeks the virus is incapable of transversing the lens capsule so that the lens is immune. Maternal infections: • Altough the lens opacities (which may be unilateral or bilateral) are usually present at birth, they may occasionally develop several weeks or even months later. • The virus has been shown to be capable of persisting within the lens for up to 3 years postnatally. Maternal drug ingestion: • Thalidomide • Corticosteroids Leukocoria • literally means " white pupil « • Leukocoria can be caused by abnormalities in the lens (eg, cataract), vitreous (eg, hemorrhage), or retina (eg, retinoblastoma) Causes of Leukocoria • Retinoblastoma • Persistent fetal vasculature • Retinopathy of prematurity • Cataract • Coloboma (fissure or cleft) of choroid or optic disc • Uveitis • Toxocariasis • Coats disease • Vitreous hemorrhage • Retinal dysplasia Syndromes: • Down’s syndrome chromosomal defect: trisomy 21 bilateral cataracts, Blue dot cataract, strabismus, keratoconus, iris hypoplasia Brushfield spots and unusual disc vasculature, epicanthic folds, myopia, • Werner’ s syndrome: premature aging, growth retardation, beaked nose , alopecia skin wrinkling, bilateral cataracts • Rothmund -Thomson syndrome: is characterized by poikiloderma; sparse hair, eyelashes, and/or eyebrows; small stature; skeletal and dental abnormalities; cataracts; and anincreased risk for cancer, especially osteosarcoma. Hereditary • 1/3 of all congenital cataracts are hereditary and unassociated with any of the metabolic or sistemic disorders. • The mode of inheritance is usually dominant. Morphological: • • • • • • Capsular Subcapsular Nuclear Cortical Lamellar Sutural According to maturity • Immature: Scattered opacities are seperated by clear zones. • Mature: Cortex is totally opaque • Intumescent: The lens has become swollen by imbibed water.It can be mature or immature • Hypermature: Mature cataract which has become smaller and has a wrinkled capsule due to leakage of water out of lens. • Morgagnian: Hypermature cataract in which total liquefaction of the cortex has allowed the nucleus to sink inferiorly. Classification according to maturity Immature Hypermature Mature Morgagnian According to the age of onset • • • • • Congenital Infantile Juvenile Presenile Senile Abnormalities of the lens shape: • Coloboma: wedge shaped defect / indentation of the lens in the periphery • • • • • Anterior lenticonus: anterior axial bulge Posterior lenticonus:anterior axial bulge Lentiglobus: hemispherical protrusion of the lens Microphakia:small than normal diameter Microspherophakia: small in diameter and spherical in shape Coloboma Ocular associations Coloboma of iris Coloboma of choroid Giant retinal tear Lenticonus Posterior Posterior axial bulge • Unilateral - usually sporadic • Bilateral - familial or in Lowe syndrome • Anterior Central 3-4 mm of the lens • Anterior axial bulge • Associated with Alport syndrome LOWE SYNDROME • Oculocerebrorenal syndrome • Error of aminoacid metabolism • X-linked inheritance pattern • Frontal prominence and sunken eyes • Proteinuria • Fanconi syndrome • Renal tubular acidosis • Areflexia • Muscular hypotonia • Mental retardation • Glaucoma • Posterior polar cataract + lenticonus ALPORT SYNDROME • XLD inheritance • Anterior lenticonus • Pigmentary retinopathy • Chronic renal failure • Sensorineural deafness • Hematuria Small lens Microphakia • • Small diameter Systemic association - Lowe syndrome Microspherophakia • Small diameter and spherical • May be familial (dominant) • Systemic association - Weill-Marchesani syndrome Ectopia lentis • Ectopia lentis is a displacement of the lens and may be congenital,developmental or acquired. • A subluxated lens is partially displaced from its normal position but remains in the pupillary area. • A luxated or dislocated lens is completely displaced from the pupil implying seperation of all zonular attachments. Ectopia lentis • Findings associated with subluxation of the lens include decreased vision,marked astigmatism,monocular diplopia and iridonesis. • Potential complications of ectopia lentis include cataract and displacement of the lens into the anterior chamber or into the vitreous. Ectopia lentis • Dislocation into the anterior chamber or pupil may cause pupillary block and angle –closure glaucoma. Ectopia lentis • Inherited Marfan’s syndrome, Weill-Marchesani syndrome, Homocystinuria Hyperlysinaemia Familial ectopia lentis Aniridia Marfan’ syndrome • Marfan’s syndrome is a heritable disorder with ocular,cardiac and skeletal manifestations. • From 50% to 80 % of patients with Marfan’s syndrome exhibit ectopia lentis. • The lens subluxation tends to be bilateral and symmetric and is usually superior and temporal. Marfan’s syndrome • The zonuler attachments usually remain intact but become streched and elongated. • Associated ocular abnormalities in Marfan’s syndrome include axial myopia and increased risk of retinal detachment. • Children with lens subluxation may develop amblyopia if there is significant asymmetry in their refractive error or if their refractive error is uncorrected in early childhood. Autosomal dominant Systemic features of Marfan syndrome • Limb-trunk disproportion • Arachnodactyly • Pectus excavatum • Aortic dilatation, dissection and regurgitation • High-arched palate • Mitral valve prolapse Ocular features of Marfan syndrome Lens • Upward subluxation • Zonule usually intact Angle anomaly and glaucoma Retinal detachment Lattice degeneration • Cornea plana • Axial myopia Blue sclera Autosomal recessive Weill-Marchesani syndrome Systemic features Ocular features • Microspherophakia • Short stature • Anterior lens subluxation • Short stubby fingers (brachydactyly) • Angle anomaly and glaucoma • Mental handicap Ectopia lentis • Acquired: Trauma(common) Large eye(High myopia,buphthalmos) Anterior uveal tumours Chronic cyclitis(rare) Hypermature cataract Syphilis Acquired ectopia lentis Trauma Stretched zonules • Buphthalmos • Megalocornea Anterior uveal tumours High myopia Treatment • The treatment of cataract is surgical Surgical Techniques 1. Intracapsular cataract extraction (+ spectacles / contactlens / intraocular lens (IOL) ) 2. Extracapsular cataract extraction + IOL 3. Phacoemulsification + IOL Phacoemulsification • • • • • • • • • Anesthesia (topical, local, general) Incision Capsulorhexis Hydrodissection Phacoemulsification Irrigation – aspiration IOL Implantation Removal of viscoelastic substance Hydration of the incisions Phacoemulsification + IOL Implantation • • • • • • • • • Anesthesia (topical, local, general) Incision Capsulorhexis Hydrodissection Phacoemulsification Irrigation –aspiration IOL Implantation, Removal of viscoelastic substance Hydration of the incisions Complications of Cataract Surgery MAJOR- EARLY • Endophthalmitis!! – – – – – – – – Blurred vision- loss of vision Severe ocular pain Photophobia Periorbital edema Ciliary injection Chemosis (conjunctival edema) • Treatment: URGENT!! Corneal edema • Vitreous tap-biopsy Hypopyon - Collected white • Systemic antibiotics material in the anterior • Topical antibiotics-fortified chamber • Intravitreal antibiotics • Vitrectomy (pars plana vitrectomy) Complications of Cataract Surgery MAJOR-LATE • Bullous Keratopathy • IOL Malposition • Cystoid Macular Edema • Retinal Detachment Complications of Cataract Surgery OTHER – Intraoperative- Early Postoperative • • • • • • • Wound gape Anterior Chamber Hemorrhage Iris Trauma Zonular Rupture Posterior Capsular Rupture Vitreous Loss Vitreous Hemorrhage • Choroidal Hemorrhage!! Complications of Cataract Surgery OTHER- LATE • Uveitis • Glaucoma (open angle/closed angle) • Posterior Capsule Opacification: Treatment YAG laser capsulotomy • IOL Dislocation The End