YEDTEPE NVERSTES GZ HASTANES DISORDERS OF THE CORNEA

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ DISORDERS OF THE CORNEA Dr. VİLDAN ÖZTÜRK

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Aims ü Knows the diagnostic criteria and treatment of corneal infections, dystrophies and ectatic diseases ü Explains the steps of biomicroscopic corneal examination and biomicroscopic findings in diseases. ü To apprehend the importance of patients having pain in case of corneal epithelial loss. ü To be able to completely and correctly list the indications of corneal surgical techniques according to the pathology.

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Diameter 10 -13 mm Micro-megalocornea 550 micron thickness clearness collagen fibril array stable water rate %70

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Corneal nutrition Tears Limbal veins Humour aqueous

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Corneal innervation Ophtalmic branch of trigeminal nerve

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Recurrent corneal erosion

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Examination

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Corneal topography

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ CORNEAL DİSEASES 1. 2. 3. 4. Corneal Infections (KERATITIS) Ectatic Corneal Diseases Dystrophies and Degenerations Corneal Surgery

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ CORNEAL INFECTIONS 1. Bacterial keratitis 2. 3. 4. 5. Fungal keratitis Acanthamoeba keratitis Infectious crystalline keratitis Herpes simplex keratitis -Epithelial -Disciform 6. Herpes zoster keratitis

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ BACTERIAL KERATITIS Predisposing factors • Contact lens wear • Chronic ocular surface disease • Corneal hypoaesthesia Expanding oval, yellow-white, Stromal suppuration and dense stromal infiltrate hypopyon Treatment - topical ciprofloxacin 0. 3% or ofloxacin 0. 3%

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ FUNGAL KERATITIS Frequently preceded by ocular trauma with organic matter Greyish-white ulcer which may be Slow progression and occasionally surrounded by feathery infiltrates hypopyon Treatment • Topical antifungal agents • Systemic therapy if severe • Penetrating keratoplasty if unresponsive

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ ACANTHAMOEBA KERATITIS • Contact lens wearers at particular risk • Symptoms worse than signs Small, patchy anterior stromal infiltrates Perineural infiltrates (radial keratoneuritis) Ulceration, ring abscess & small, satellite lesions Stromal opacification Treatment - chlorhexidine or polyhexamethylenebiguanide

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ HERPES SIMPLEX EPITHELIAL KERATITIS • Dendritic ulcer with terminal bulbs • Stains with fluorescein • May enlarge to become geographic Treatment • Aciclovir 3% ointment x 5 daily • Trifluorothymidine 1% drops 2 -hourly • Debridement if non-compliant

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ HERPES ZOSTER KERATITIS Acute epithelial keratitis • Develops in about 50% within 2 days of rash • Small, fine, dendritic or stellate epithelial lesions • Tapered ends without bulbs • Resolves within a few days Nummular keratitis • Develops in about 30% within 10 days of rash • Multiple, fine, granular deposits just beneath Bowman membrane • Halo of stromal haze • May become chronic Treatment - topical steroids, if appropriate

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ CORNEAL ECTASIAS 1. Keratoconus 2. Keratoglobus 3. Pellucid marginal degeneration

Morphological classification of keratoconus YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Nipple cone Small and steep curvature Oval cone Larger and ellipsoidal Globus cone Largest

Signs of keratoconus Bilateral in 85% but asymmetrical YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Oil droplet reflex Vogt striae Prominent corneal nerves Bulging of lower lids on downgaze Fleischer ring & scarring Munson sign Acute hydrops

CORNEAL DYSTROPHIES 1. Anterior YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ • • Cogan microcystic. . Reis-Bucklers Meesmann Schnyder 2. Stromal • Lattice I, III • Granular I, III (Avellino) • Macular 3. Posterior • Fuchs endothelial • Posterior polymorphous

Cogan microcystic dystrophy YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ • Most common of all dystrophies • Neither familial nor progressive • Recurrent corneal erosions in about 10% of cases Dots Cysts Fingerprints Maps

Lattice dystrophy YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Progression Fine, spidery, branching lines within stroma Later general haze may submerge lesions Treatment - penetrating keratoplasty if severe

Granular dystrophy YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Onset - first decade with recurrent corneal erosions Progression Initial superficial and central crumb-like opacities Later deeper and peripheral spread but limbus spared Eventual confluence Treatment - penetrating keratoplasty if severe

Macular dystrophy YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Onset - second decade with painless visual loss Progression Initial dense, poorly delineated opacities Later generalized opacification Treatment - penetrating keratoplasty Thinning

Fuchs endothelial dystrophy YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Inheritance - occasionally autosomal dominant Onset - old age Progression Gradual increase in cornea guttata with peripheral spread Later central stromal oedema Eventually bullous keratopathy Treatment - penetrating keratoplasty if advanced

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ CORNEAL DEGENERATIONS&DEPOSITS 1. Age-related Arcus senilis 2. Lipid keratopathy 3. Band keratopathy 4. Spheroidal degeneration 5. Salzmann nodular degeneration 6. Cornea verticillata 7. Kayser-Fleischer Ring

Arcus senilis • Innocuous and extremely common in elderly • Occasionally associated with hyperlipoproteinaemia YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ • • Bilateral, circumferential bands of lipid deposits Diffuse central and sharp peripheral border • • Peripheral border separated from limbus by clear zone Clear zone may be thinned ( senile furrow)

Lipid keratopathy Primary YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Secondary result of cholesterol or fatty acid extravasation • • Rare, occurs spontaneously in avascular cornea • Usually unilateral stromal deposits without vascularization • Common, secondary to previous disciform keratitis Unilateral stromal deposits with vascularization Treatment: keratoplasty, if severe Treatment - coagulation of feeder vessels and/or keratoplasty

Band keratopathy ÜNİVERSİTESİ • Common, unilateral or bilateral. YEDİTEPE depending on cause GÖZ HASTANESİ • Subepithelial calcification • Ttrauma, surgery, some eye drops especially Pilocarpine, hipercalsemia with renal failure, sarcoidosis and certain malignancies Interpalpebral limbal opacification • Central spread of calcification • Separated by clear zone • Small holes within calcified area •

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Cornea verticillata - Fabry's disease -alpha-galactosidase A deficiency -Variety of drugs -amiodarone, -chloroquine, -meperidine, -indomethacin, -chlorpromazine -tamoxifen

YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Kayser-Fleischer Ring -Copper at descemet Wilson disease: abnormalities basal ganglia of the brain, liver cirrhosis, splenomegaly, involuntary movements, muscle rigidity, psychiatric disturbances, dystonia and dysphagia

CORNEAL SURGERY YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ 1. Keratoplasty (Penetrating , lamellar) 2. Keratoprosthesis 3. Refractive surgery • Radial keratotomy (RK) • Photorefractive keratectomy (PRK) • Laser assisted subepithelial keratectomy(LASEK) • Epithelial Laser in-situ keratomileusis (Epi. LASIK) • Laser in-situ keratomileusis (LASIK) • Conductive keratoplasty (light-touch) (CK) • Intracorneal ring segments (ICR)

Penetrating Keratoplasty YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ 1. Indications • Optical (e. g. bullous keratopathy, dystrophies) • Tectonic (e. g. severe stromal thinning, descemetocele) • Therapeutic (e. g. severe keratitis) • Cosmetic 2. Adverse prognostic factors • Severe stromal vascularization • Absence of corneal sensation • Progressive conjunctival inflammation (e. g. pemphigoid) • Tear film dysfunction • Glaucoma

Technique of penetrating keratoplasty YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Excision of donor tissue a, b - Excision of host tissue c - Fixation of donor tissue

Keratoprosthesis Indications YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Bilateral blindness from ocular pemphigoid, chemical burns or repeated graft failure Technique Insertion of artificial lenticule into corneal stroma Main complications Retrolenticular membrane formation • Glaucoma •

Radial keratotomy Decreases myopia by flattening cornea Deep incisions from edge of optical zone to limbus • YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ • Main indications Main complications Stable myopia of up to 8 D • Accidental perforation • Otherwise normal cornea • Intrastromal epithelial cysts •

Photorefractive keratectomy ( PRK ) YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ Indications • Stable myopia up to 6 D with astigmatism no more than 3 D • Hypermetropia up to 2. 5 D Technique Reshaping of cornea by excimer laser ablation of Bowman layer and anterior stroma Main complication Subepithelial haze which usually resolves after 1 -6 months

Laser in-situ keratomileusis (LASIK) Indications - similar to PRK but. YEDİTEPE corrects higher degrees of myopia ÜNİVERSİTESİ GÖZ HASTANESİ Technique Complications • Thin flap of cornea fashioned • Wrinkles in flap • Bed treated with excimer laser • Cellular interface proliferation • Flap repositioned

Non-contact laser thermal keratoplasty Indications • Patients over 40 years with hypermetropia up to 2 D • Following overcorrection of myopia YEDİTEPE ÜNİVERSİTESİ GÖZ HASTANESİ • • Corneal curvature is steepened by application of laser heat to stroma Holmium laser spots applied to mid-cornea