1 OUTER COAT 2 MIDDLE COAT 3 INNER

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1. OUTER COAT 2. MIDDLE COAT 3. INNER COAT *

1. OUTER COAT 2. MIDDLE COAT 3. INNER COAT *

Tough Fibrous Coat Post 5/6 th of Globe White & Opaque Sclera Radius---12 mm

Tough Fibrous Coat Post 5/6 th of Globe White & Opaque Sclera Radius---12 mm *

Tough Fibrous Coat Ant 1/6 th of Globe Transparent Cornea Radius---8 mm *

Tough Fibrous Coat Ant 1/6 th of Globe Transparent Cornea Radius---8 mm *

Junction of Cornea and Sclera Contains 1. Trabecular Meshwork 2. Canal of Schlemn *

Junction of Cornea and Sclera Contains 1. Trabecular Meshwork 2. Canal of Schlemn *

Verticle-------10. 6 mm Horizontal---11. 7 mm Thickness Central portion----0. 52 mm Peripheral portion----1 mm

Verticle-------10. 6 mm Horizontal---11. 7 mm Thickness Central portion----0. 52 mm Peripheral portion----1 mm *

Three Layers 1. Epithelium & its Basement 2. Stroma & its ant condensation (

Three Layers 1. Epithelium & its Basement 2. Stroma & its ant condensation ( Bowman Zone) 3. Endothelium & its Basement (Descemet Membrane) *

From Anterior to Posterior 1. Epithelium 2. Bowman Zone 3. Stroma 4. Descemet Membrane

From Anterior to Posterior 1. Epithelium 2. Bowman Zone 3. Stroma 4. Descemet Membrane 5. Endothelium *

*50 -60 µm thick *Covers the stroma anteriorly *Continuous with epithelium of conjunctiva *Life

*50 -60 µm thick *Covers the stroma anteriorly *Continuous with epithelium of conjunctiva *Life of epithelial cells is 7 days *Prevent aqueous solutions to penetrate *

*Surface cell layer *Wing cell layer *Basal cell layer *Basement membrane *

*Surface cell layer *Wing cell layer *Basal cell layer *Basement membrane *

90% of the corneal thickness *Bowman Zone *Lamellar Stroma Once deformed its typical structure

90% of the corneal thickness *Bowman Zone *Lamellar Stroma Once deformed its typical structure is not restored *

*Descemet membrane (Regenerates) *Endothelium Single layer of cells Cells are tightly bound together Responsible

*Descemet membrane (Regenerates) *Endothelium Single layer of cells Cells are tightly bound together Responsible for dehydration * Never regenerates

*Central cornea is avascular *Corneoscleral limbus is generously supplied by anterior conjuntival branches of

*Central cornea is avascular *Corneoscleral limbus is generously supplied by anterior conjuntival branches of the anterior ciliary arteries *Aqueous humor and tear film provides nutrients *

*Branches of the ophthalmic division of trigeminal nerve and are solely sensory *Most are

*Branches of the ophthalmic division of trigeminal nerve and are solely sensory *Most are concentrated in the anterior stroma beneath the Bowman zone and send branches forward into epithelium *Descemet membrane and * endothelium are not innervated

*The microvilli of the anterior surface of the squamous cell layer are wet by

*The microvilli of the anterior surface of the squamous cell layer are wet by the mucin of tear film *These cells are joined by tight junctions that exclude water soluble substances *

*Tight junctions of the epithelial cells *Endothelial pump mechanism *Absence of blood vessels *Absence

*Tight junctions of the epithelial cells *Endothelial pump mechanism *Absence of blood vessels *Absence of pigments *Scarcity of cell nuclei in stroma *Regular structure of stroma *

Superficial 1. Punctate epithelial erosions Tiny , slightly depressed, epithelial defects which stain with

Superficial 1. Punctate epithelial erosions Tiny , slightly depressed, epithelial defects which stain with flourescein but not with rose Bengal PEE are non specific and may develop in a wide variety of keratopathies *

Superficial 2. Punctate epithelial keratitis It is the hallmark of viral infections. *Swollen epithelial

Superficial 2. Punctate epithelial keratitis It is the hallmark of viral infections. *Swollen epithelial cells *Visible unstained *Stains with rose bengal *

Superficial 3. Epithelial Oedema Sign of *Endothelial decompensation *Severe acute elevation of IOP *

Superficial 3. Epithelial Oedema Sign of *Endothelial decompensation *Severe acute elevation of IOP *

Superficial 4. Filaments Small coma shaped mucus strands lined with epithelium. One end attached

Superficial 4. Filaments Small coma shaped mucus strands lined with epithelium. One end attached with epithelium *

Superficial 5. Pannus Inflammatory or degenerative ingrowth of fibro vascular tissue from limbus *

Superficial 5. Pannus Inflammatory or degenerative ingrowth of fibro vascular tissue from limbus *

Stromal Lesions 1. Infiltrates Focal areas of active stromal inflammation 2. Oedema Increased corneal

Stromal Lesions 1. Infiltrates Focal areas of active stromal inflammation 2. Oedema Increased corneal thickness Decreased transparency 3. Vascularization *

Lesions of Descemet Membrane 1. Breaks Corneal enlargement Keratoconus Birth trauma 2. Folds (Striate

Lesions of Descemet Membrane 1. Breaks Corneal enlargement Keratoconus Birth trauma 2. Folds (Striate Keratopathy) Surgical trauma Ocular hypotony Stromal oedema *

* * * Control of infection Control of inflammation Promotion of re-epithelialization – lubrication

* * * Control of infection Control of inflammation Promotion of re-epithelialization – lubrication – lid closure – bandage soft contact lens *Prevention of perforation – tissue adhesive glue – conjunctival flap – systemic immunosuppressive agents * Corneal grafting *

*Ocular surface disease: Trauma, post-herpetic corneal disease, bullous keratopathy, corneal exposure, dry eye and

*Ocular surface disease: Trauma, post-herpetic corneal disease, bullous keratopathy, corneal exposure, dry eye and diminished corneal sensation. *Contact lens wear *

Pathogens which can produce corneal infection in intact epithelium. *1. Neisseria gonorrhoeae *2. Corynebacterium

Pathogens which can produce corneal infection in intact epithelium. *1. Neisseria gonorrhoeae *2. Corynebacterium diphtheriae *3. Listeria *4. Haemophilus *

*Oval, yellow-white, densely opaque stromal suppuration surrounded by relatively clear cornea *

*Oval, yellow-white, densely opaque stromal suppuration surrounded by relatively clear cornea *

*Thick mucopurulent exudate, diffuse liquefactive necrosis and semi-opaque ground glass appearance of adjacent stroma

*Thick mucopurulent exudate, diffuse liquefactive necrosis and semi-opaque ground glass appearance of adjacent stroma *

*Shallow ulceration, grey-white pleomorphic suppuration and diffuse stromal opalescence. Endotoxins may induce ring-shaped corneal

*Shallow ulceration, grey-white pleomorphic suppuration and diffuse stromal opalescence. Endotoxins may induce ring-shaped corneal infilterates *

*History *Clinical examination (including staining and sensitivity) *Hospitalization *Corneal scrapping *Treatment *

*History *Clinical examination (including staining and sensitivity) *Hospitalization *Corneal scrapping *Treatment *

*Topical antibiotics – combination therapy with fortified amino glycoside and fortified cephalosporin or monotherapy

*Topical antibiotics – combination therapy with fortified amino glycoside and fortified cephalosporin or monotherapy with fluoroquinolone. Initial instillation at hourly intervals. *Subconjunctival injections *Systemic ciprofloxacin 750 mg BD *

*Cycloplegics *Steroid therapy (controversial) *Corneal biopsy or excisional keratoplasty

*Cycloplegics *Steroid therapy (controversial) *Corneal biopsy or excisional keratoplasty

*Wrong diagnosis *Wrong treatment *Drug toxicity *

*Wrong diagnosis *Wrong treatment *Drug toxicity *

*Filamentous fungal keratitis - Fusarium * –Aspergillus

*Filamentous fungal keratitis - Fusarium * –Aspergillus

*Greyish-white ulcer with indistinct margins *Surrounded by feathery infilterates *Ring infilterate *Endothelial plaque *Hypopyon

*Greyish-white ulcer with indistinct margins *Surrounded by feathery infilterates *Ring infilterate *Endothelial plaque *Hypopyon *

*Usually develops in pre-existing corneal disease or immunocompromised patient *Yellow-white ulcer *Dense suppuration *

*Usually develops in pre-existing corneal disease or immunocompromised patient *Yellow-white ulcer *Dense suppuration *

*Suppurative bacterial keratitis *Herpetic stromal necrotic keratitis *

*Suppurative bacterial keratitis *Herpetic stromal necrotic keratitis *

*Culture *Biopsy *Antifungal therapy – Initially broad- spectrum econazole 1% topically – Then depending

*Culture *Biopsy *Antifungal therapy – Initially broad- spectrum econazole 1% topically – Then depending upon sensitivity natamycin or imidazole for 6 weeks *Systemic ketoconazole *Therapeutic penetrating keratoplasty *

*Protozoan – active (trophozoite) dormant (cystic) *Common in swimmers and CL wearers * –

*Protozoan – active (trophozoite) dormant (cystic) *Common in swimmers and CL wearers * –

*Blurred vision and disproportionate pain *Patchy anterior stromal infilterates *Perineural infilterates (radial keratoneuritis) *Infilterates

*Blurred vision and disproportionate pain *Patchy anterior stromal infilterates *Perineural infilterates (radial keratoneuritis) *Infilterates coalesce –ring abcess, ulceration and hypopyon *White satellite lesions *

*Corneal scrappings stained with calcoflour white *Corneal biopsy *Treatment with chlorhexidine, polyhexamethylenebiguanide drops, dipropamidine

*Corneal scrappings stained with calcoflour white *Corneal biopsy *Treatment with chlorhexidine, polyhexamethylenebiguanide drops, dipropamidine and propamidine. *Therapeutic penetrating keratoplasty *

* Primary ocular herpes: - Blepharoconjunctivitis - Keatitis (punctate epithelial)

* Primary ocular herpes: - Blepharoconjunctivitis - Keatitis (punctate epithelial)

*Opaque cells arranged in a course punctate or stellate pattern *Central desquamation leads to

*Opaque cells arranged in a course punctate or stellate pattern *Central desquamation leads to a linear branching ulcer. –Fluorescein stain – Rose Bengal stain –Diminished corneal sensitivity *Anterior stromal infilterates *Geographical or amoeboid ulcer *

*Herpes zoster keratitis *Healing corneal abrasion *Pseudodendrites due to soft contact lens *Acanthamoeba keratitis

*Herpes zoster keratitis *Healing corneal abrasion *Pseudodendrites due to soft contact lens *Acanthamoeba keratitis *Drug toxicity *

*Antiviral therapy – Acycloguanosine 3% ointment – Trifluorothymidine 1% drops – Adenine arabinoside 3%

*Antiviral therapy – Acycloguanosine 3% ointment – Trifluorothymidine 1% drops – Adenine arabinoside 3% ointment, 0. 1% drops – Idoxuridine *Debridement (with sterile cotton- tipped bud 2 mm beyond the edge of ulcer) *

*Stromal necrotic keratitis *Disciform keratitis *

*Stromal necrotic keratitis *Disciform keratitis *

*Predominantly affects children *Etiology Tuberculosis – Delayed hypersensitivity reaction to staphylococcal or other bacterial

*Predominantly affects children *Etiology Tuberculosis – Delayed hypersensitivity reaction to staphylococcal or other bacterial antigen * –

*Photophobia, lacrimation and blepharospasm. *

*Photophobia, lacrimation and blepharospasm. *

*Conjunctival: Pinkish-white nodule surrounded by hyperaemia *Corneal: May resolve spontaneously or extend radially to

*Conjunctival: Pinkish-white nodule surrounded by hyperaemia *Corneal: May resolve spontaneously or extend radially to the cornea. May cause severe ulceration or perforation. *

*Short course of topical steroids *Topical antibiotics *

*Short course of topical steroids *Topical antibiotics *

*Onset at puberty *Central or paracentral stromal thinning *Apical protrusion *Irregular astigmatism *Autosomal dominant

*Onset at puberty *Central or paracentral stromal thinning *Apical protrusion *Irregular astigmatism *Autosomal dominant transmission with incomplete penetrance proposed *

*By keratometry: Mild (< 48 D), moderate (48 -54 D) severe (> 54 D)

*By keratometry: Mild (< 48 D), moderate (48 -54 D) severe (> 54 D) *By morphology: – Oval – Globus Nipple cones *

*Ophthalmoscopy: Oil droplet reflex *Retinoscopy: Irregular scissor reflex *Keratometry: Irregular astigmatism (principal meridians no

*Ophthalmoscopy: Oil droplet reflex *Retinoscopy: Irregular scissor reflex *Keratometry: Irregular astigmatism (principal meridians no longer 90 degree apart and mires cannot be superimposed) *Placido disc: Irregular reflected ring *Slit-lamp: Very fine deep stromal striae (Vogt lines). *

* *Decreased visual acuity *Munson sign *Fleischer ring *Corneal scarring *Acute hydrops

* *Decreased visual acuity *Munson sign *Fleischer ring *Corneal scarring *Acute hydrops

*Spectacle correction *Contact lenses *Penetrating keratoplasty *

*Spectacle correction *Contact lenses *Penetrating keratoplasty *