1-11 cornea
TRANSCRIPT
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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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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914
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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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914
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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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914
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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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914
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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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914
(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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Dr / M. Abd Ulghaffar (MASS) / 016 570 1914
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