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Medical Ophthalmology

Dr / M. Abd Ul-ghaffar (MASS) 2009

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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914

Anatomy

Gross Anatomy:- Site: Ant. 1/6 of outer coat of eye.

Curvedsmoothly:Shape-

)lustre(clear and brilliant,ransparentt:Transparency- mm11=Vertical&mm12=Horizontal:Diameter- mm1=Peripheral&mm5.0=Central:Thickness-

D42=Refractive power-

.)ostPto.ntAfrom(layers-5:Minute Anatomy layers6-5(: Epithelium-1(

.epitheliumkeratinizednontratified squamousS- - Quickly regenerates when cornea is injured.not regeneratedIf destroye.structurlessClear ,Elastic: Bowmans membrane-2

: Stroma-3 - The thickest layer (about 90%)

,tiny collagen fibrilsof regular lamellaetransparent150-100Composed of - .ylaritCcornea itsgiving, parallel to each other ningunr

: Descemets membrane-4 asily regeneratesE,)descematocele(esistantR ,Elastic-

:m Endotheliu-5 - Single layer of hexagonal flat cells.

corneal dehydrationmportant for I-

Nutrition: (Cornea is a vascular)

* By diffusion from(Limbal capillaries, Aqueous humour, Tear film) Nerve Supply:

,myelinated- Non(nervous plexusLong ciliary ns-2 Nasociliary nOphthalmic nnth5*very low threshold) in: Stroma, Subepithelium, Intraepithelium

* Nerves of the surrounding conjunctiva.

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Excellence Ophthalmology:

Definition: Inflammation of cornea, being infective or non infective

Classification:

Keratitis

Superficial Keratitis Interstitial Keratitis (Inflammation of epithelium + superficial stroma) (Intact epithelium + Inflammation of stroma)

Ulcerative Keratitis- Non )Ulcer l Cornea( Ulcerative Keratitis * loss of epithelium + superficial stroma.* may be:( bacterial, viral, fungal, protozoal)

( Bacterial CU, Herpes Simplex Keratitis, HZO )

Definition: Loss of epithelium + superficial stroma.

Ocular emergencies:Etiology:

Predisposing factors- I

- CL wear - Dry eyes - Traumatic abrasion as rubbing lash, - Loss of sensation - Exposure

) : MO( Causative Organism- II

- Bacteria attacking healthy corneal epithelium: ( N. gonorrhoea, C.diphtheria, Listeria, H. aegypticus)

- Bacteria needing corneal abrasions: Strept, Staph, Pneumococci, Pseudomonas

: Sources of infection- III Chronic Conjunctivitis, Blepharitis, Dacryocystitis

Bacterial Corneal Ulcers

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Treatment ED1%Atropine(Mydriatic Cycloplegics-1(

Ant. uveitis, Pain, Post. synechia ) Local broad spectrum antibiotics are tried first ( ntibioticsATopical-2

- Fluoroquinolones e.g. Ciprofloxacin 0.3% almost all MOs- Aminoglycosides + Cephalosporinesgram+ve + -ve cocci

:Patching-3 Epithelialization, Pain+ Photophobia

:CLBandage-4 Epithelialization

5- Surgery(Surgical intervention is indicated in certain specific situations) ry glaucoma2ehypopyon,metoceleedescParacentesis-

small perforationsadhesive glueTissue- large perforationsKeratoplastyherapeuticT-

ensationS!loss of cornea,exposurelapsFhaphy and conjr r Tarso-

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I. Her es Sim lex Keratitis

Definition: It is the classical corneal lesion in recurrent HSV KeratitisClinical Picture:

1-Epithelial Infiltration:ve Rose Bengal/ +Dendritic e round knobsStellate)linear (StriateSPK -

GeographicAmoeboid

:lium Sheding of infected epithe-2 dendritic ulcerSheding-

:double stainstained by- bed2%Fluorescein.

margin1%Rose Bengal. bed of ulcer is insensitive:Corneal Hyposthesia-3 heal e out opacitylesion mayIf BM and stroma are not involved-4

vascularized-superficial and nonThe ulcer is characteristically-5

:Treatment+ A- ttt of CU

Acyclovir: 3% , EO , 5-times /day B- Antiviral drugs

C- Surgery: line of simple surgical treatment to be followed by intensive antiviral topical medicationsto remove infected epithelium is oneDebridement-

- Cautery by tincture iodine 7.5 %, or absolute Alcohol comeasis done to manage opacifiedLamellar Penetrating keratoplasty-

SPK Dendritic Ulcer Amoeboid Ulcer Geo ra hical Ulcer

( SteroidsTopical=)- absolutely contraindicated in presence of herpetic ulcer

perforationor amoeboid ulcer -

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Definition: Unilateral affection of Ophthalmic n. of 5th n. by HZV

Clinical Picture: along distribution of nervesneuralgiasevere,FAHMSevere:Prodroma.A

B. Skin lesions:(frontal, lacrimal, and nasociliary nerves) carsS punched outlcersUcrustingustulesPapulesP

Ocular lesions.C - conjunctiva:

Mucopurulent conjunctivitis - sclera:

leritiscSEpiscleritis and- Cornea:

SPK .I Microdendrites.II Nummular keratitis.III Disciform keratitis.IV

- Iris, CB: veitisUAnterior

- Retina: Acute retinal necrosis

Neurological.D 6,5,4,3,2:Cranial Nerve affection-

ephalitiscEn-

chronic,verese:neuralgiaPost herpetic- Treatment:

+ ttt of CU-AOcular and Skin lesionssantibiotic-teroidScyclovir andAopicalT-B

)7X1X5(tabletsmg800):oviraxZ(cyclovir ASystemic-C

II. HZO

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(Conical Cornea)

ectasia and apical protrusionstromal thinningrogressive centralP:Definition

Etiology: unknown, but may be:- - hereditary- developmental- endocrinal- degenerative

Clinical Picture:

: Incidence .of cases%85inBilateral-

progresses for few years)yrs20-10(around pubertystarts- or Marfans syndrome,Downs syndrome:systemicther oeassociated-

Spring catarrh:cular diseaseso glassesnt changing of equeFr *: s Symptom

: Signs profile view/shaped deformityoneC-

lit lampS/)Vogt striae(scarring and opacities,Corneal thinning- the coneof iron deposits at the base:rings'Fleischer -

gazeon downwardLLangulation of :signs'Munson-

Management: (ttt) can he used in early cases before astigmatism becomes irregular pectaclesS-

may help in irregular astigmatismCLRigid- -PKP(enetrating keratoplastyP(

-Thermokeratoplasty -Epikeratophakia

Keratoconus

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Keratoplasty

Corneal Opacities

. Egypt inopacities are the commonest cause of blindnesslCornea

VA by: blocks the passage of light raysamense central leucoD.1

glaucomarynd2eucoma adherent may be associated withL.2 shionscatter the rays in irregular fa):opacities!faint cornea( Nebulae.3

Management: r Lamellar keratoplasty or Excimer lase,CL)causing irregular astigmatism( Nebulae.1

eratoplastyK enetratingPeucomaLentralC.2

urgicallySor ,CL,lassesG)daccording to the astigmatism induce(Peripheral scars.3 colored CL problemonly cosmeticIf .4

Definition:

Removal of diseased corneal part, replacing it by clear donor`s graft (cadaveric eye

, from autogenous graft or allograftTypes:

A) Lamellar B) Penetrating

Indications:

- Optical: corneal opacities

Tectonic: keratoconus - Therapeutic: resistant corneal ulcers, perforation, fistula -

Cosmotic: leucoma in blind eye -

Penetrating Lamellar

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