cornea presentation for undergraduate

1. Cornea
By/Mohamed Ahmed El –ShafieMohamed Ahmed El –Shafie
Assistant Lecturer in ophthalmology department
KafrELShiekh University

2. Anatomy of the Cornea

3. Anterior 1Anterior 1/6 of outer coat/6 of outer coat
Curved & Domshaped
Fibrous, Transparent & No BVsFibrous, Transparent & No BVs
Diameter : Horizontal 12mmDiameter : Horizontal 12mm
Vertical 11mmVertical 11mm
Thickness: Central 0.5 - 0.6mmThickness: Central 0.5 - 0.6mm
Peripheral 0.8 – 1.0mmPeripheral 0.8 – 1.0mm
Refractive Power : 42 DRefractive Power : 42 D
( What is The LIMBUS ?)( What is The LIMBUS ?)

4. 5 Layers of the Cornea
a.Epithelium: 5-6 layers of cells
b.Bowman’s membrane: clear acellular layer
c.Stroma: 90% of corneal thickness
 collagen fibrils that are parallel to each other
d.Descemet’s membrane: basal lamina of corneal
endothelium
e.Endothelium: single layer of cells which act as a
“pump”

5. NERVE SUPPLY OF THE CORNEANERVE SUPPLY OF THE CORNEA
55THTH
C.NC.N
OPHTH. division NASOCILIARY N 2 LongOPHTH. division NASOCILIARY N 2 Long CILIARY NCILIARY N
PAIN & COLD & SUPERFICIAL TOUCHPAIN & COLD & SUPERFICIAL TOUCH

6. Cornea gets its nutrition from:
1. Limbal vessels
2. Aqueous
3. Tears

7. Transparency of the Cornea
1. Uniform structure
2. Avascularity
3. Deturgescence

8. Clinical tests

9. Corneal senstion test
= corneal reflex test
= Blinking reflex
• Aim
• Technique
• result

10. • Causes of lost corneal reflex
• Receprors:
Keratitis: HSV,HZV, Keratomalacia,
Corneal scars
High IOP
Topical anaeathesia
CL
• Afferent:
• Center :
• Efferent:
5th
n. lesion
Occipital cortex lesion
7thh
n. lesion (facial palsy)
Corneal reflex

11. KERATITISKERATITIS
SUPERFICIAL KERATITISSUPERFICIAL KERATITIS
INTERSTITIAL KERATITIS:INTERSTITIAL KERATITIS:
Non Suppurative iflammation of the Stroma
- Syphilis, T.B., Leprosy
DEEP KERATITISDEEP KERATITIS

12. SUPPURATIVE SUPERFICIALSUPPURATIVE SUPERFICIAL
KERATITSKERATITS
(CORNEAL ULCERS)(CORNEAL ULCERS)
DEFINITIONDEFINITION
Localized Necrosis of Sup. StromaLocalized Necrosis of Sup. Stroma
with destruction of overlying Epith.with destruction of overlying Epith.
ETIOLOGYETIOLOGY
Predisposing FactorsPredisposing Factors
Causative OrganismsCausative Organisms

13. Predisposing FactorsPredisposing Factors
LocalLocal
a) Traumaa) Trauma
- Abrasion- Abrasion
-- FB , Rubbing lashes , PTDs , CLFB , Rubbing lashes , PTDs , CL
b) Loss of corneal sensationsb) Loss of corneal sensations
c) Ocular causesc) Ocular causes (( xerosis, A deficiency, Lagoph.).)
d) Prolonged use of Steroidsd) Prolonged use of Steroids
GeneralGeneral
malnutrition Pregnancymalnutrition Pregnancy
Diabetes Liver & Renal FailureDiabetes Liver & Renal Failure

14. CAUSATIVE ORGANISMSCAUSATIVE ORGANISMS
a) Bacterial e.g. Gono, Diphth., Pneumo,a) Bacterial e.g. Gono, Diphth., Pneumo, Staph, StreptStaph, Strept….….
b) Fungal ( not common )b) Fungal ( not common )
c) Viral e.g. Herpes Simplex and Zosterc) Viral e.g. Herpes Simplex and Zoster
d) Acanthamoeba (C.L.)d) Acanthamoeba (C.L.)

15. CLINICAL PICTURECLINICAL PICTURE
SymptomsSymptoms
Pain Severe ( FB or pricking sensation )Pain Severe ( FB or pricking sensation )
Irritation of nerve endingsIrritation of nerve endings
PhotophobiaPhotophobia
LacrimationLacrimation
BlepharospasmBlepharospasm
Diminution of visionDiminution of vision
SignsSigns
Lids: OedemaLids: Oedema
Conj.: Ciliary injectionConj.: Ciliary injection
Cornea: Loss of luster, Grey infilt., Oedema & +ve FTCornea: Loss of luster, Grey infilt., Oedema & +ve FT
Iris: Tender CB, Const. pupil & Aqueous flareIris: Tender CB, Const. pupil & Aqueous flare

16. COMPLICATIONS OF CORNEAL ULCERSCOMPLICATIONS OF CORNEAL ULCERS
A) Non Perforated corneal ulcer
Early Complications
(1)(1) 2ry Iridocyclitis : ( Toxins )2ry Iridocyclitis : ( Toxins )
(2) 2ry Glaucoma(2) 2ry Glaucoma : Open angle glaucoma: Open angle glaucoma
(3) Descematocele :
Late Complications (Healing abnormalities)
(1) Corneal opacity ( Nebula, Macula or Leucoma non adherent )
(2) Keratectasia:( weak corneal scar)
(3) Pseudoptregium

17. B) COMP. OF PERFORATED CORNEAL ULCERSB) COMP. OF PERFORATED CORNEAL ULCERS
Early Complications
(1) Iris Prolapse
(2) Anterior synechia ( Small periph. Perforation)
(3) Corneal Fistula ( Small central perforation )
Lost AC IOP River Green Sign
(4) Malposition of the Lens
Sublaxation Ant. Dislocation Extrusion
(5) Intra-ocular Hge
Hyphema Vit., Ret. And choroidal hges
(6) Macular and Optic Disc Oedema
(7) Endo or Panophthalmitis

18. Late complications
(1) Ant.Polar Cataract (Toxins )
(2) Leucoma Adherent ( Large Peripheral Perforation )
- AC irregular
- Pupil pear shaped
(3) Ant. Staphyloma ( partial or total )
(4) 2ry Glaucoma (closed angle by PAS )
(5) Atrophia bulbi ( atrophy of the cil. processes )
B) COMP. OF PERFORATED CORNEAL ULCERS (cont.)B) COMP. OF PERFORATED CORNEAL ULCERS (cont.)

19. MANAGEMENT OF CORNEAL ULCERSMANAGEMENT OF CORNEAL ULCERS
INVESTIGATIONS + TREATMENT
A) Corneal Scrapping ( Culture & Sensitivity )
Gram Stain for Bacteria
Geimsa Stain for Trachoma & Acanthamoeba
Silver Stain for Fungi
B) Local ttt (1) Atropine sulphate 1%
(3) Bandage or Dark Glasses
(4) Counter irritant
(2) Dressings ( Antibiotic dps & oint )
C) Systemic ttt
Antibiotics Analgesics
Vitamins A & C

20. CORNEAL ULCERSCORNEAL ULCERS
Primary Corneal Ulcers
- Infected Corneal ulcer
Hypopyon Ulcers (Bacterial)
Herpetic Ulcers (Viral)
Mycotic Ulcers (Fungal)
Acanthamoeba K (Protozoa)
- Non-Infected Corneal ulcer
Mooren’s Ulcer
Keratomalacia
Atheromatous Ulcer
Ulcer with Lagophthalmos
Neuroparalytic Ulcer
Traumatic Ulcer
Secondary Corneal Ulcers

21. HYPOPYON ULCERHYPOPYON ULCER
Predisposing Factors
Causative Agents:
Pneumococci ( 80% )
Clinical Picture
Symptoms Pain
Photophobia
Lacrimation
Blepharospasm
Poor vision

22. Signs ( Acute Serpiginous ulcer )
- Ulcer Near the centre
Central advancing Edge
Crescentic, undermined,
preceded by dense infiltration
Peripheral Healing Edge
Flat, Epithelialized, Vascularized
- Posterior Abscess :
Dense infiltration in front of D M
- Hypopyon in the Anterior Chamber
( Sterile Pus )

23. Fungal UlcerFungal Ulcer
Predisposing Factors
Trauma with green plant
Use of Steroids
Contact Lenses
Causative Agent
Fusarium ( Filamentary fungi )
Candida ( Yeast forming fungi )

24. Acanthamoeba keratitisAcanthamoeba keratitis
 Aetiology
Protozoa ( Tap water and Swimming pools )
70% of cases are C L wearers
 Clinical Picture
Punctate or Dendritic K
Partial or Complete ring of Infiltration

25. Dendritic Corneal UlcerDendritic Corneal Ulcer
Herpes Simplex Virus ( Epitheliotropic )
1ry infection in early childhood
Dormant in 5th
Ganglion
Recurrence with body resistance
Predisposing factors
Fevers (Influenza, Common cold and Pneumonia)
Menstruation
Drugs ( Immunosuppressive drugs or Steroids)
Clinical Picture
1ry Ocular infection Dermato-blepharitis
Follicular Conjunctivitis
Epithelia Keratitis

26. Recurrent Ocular Infection (C/P of H. Keratitis)
(A) Blepharoconjunctivitis
(B) Epithelial Keratitis: Dendretic Herpetic Corneal Ulcer
Dendritic appearance
Long course with tendency to Recurrence
Superficial ( never perforate except in … )
Never Vascularised
Hypothesia
Double Stain Test
C) Amoeboid Ulcer
due to immunity or local Steroids

27. Herpes Zoster OphthalmicusHerpes Zoster Ophthalmicus
Varicella-Zoster (Neurotropic) Virus
Old age - Immunity
Clinical Picture :
Lids : Dermatoblepharitis ( pain and rash )
Keratitis : ( Hutchinson’s rule )
Epithelial Keratitis ( Punctate or dendritic )
Interstitial Keratitis

28. Ulcer with LagophthalmosUlcer with Lagophthalmos
 Bell’s phenomena
 Symptoms
as usual corneal ulcer ( of vision is not marked..why?)
 Signs
Incomplete lid closure
Ciliary injection & +ve flurorescein
Ulcer in lower 1/3 with straight upper border
 Treatment
Usual ttt
Methyl cellulose drops 0.5% several times/day

29. KeratomalaciaKeratomalacia
 Non infective ulceration and melting of the cornea
Vitamin A (malnourished infants or malabsorption in adults)
 Clinical Picture
Loss of corneal luster
Melting of the cornea
Corneal hypothesia
Conjunctiva: dry with Bitot’s spots
 Treatment
Vit. A injection (200,000 IU/day)
Topical vit. A in early cases
Surgical ttt in late cases : Conj. Flap
Therapeutic CL
PK

30. Neurotrophic (Neuroparalytic) KeratitisNeurotrophic (Neuroparalytic) Keratitis
Corneal Sensation
Aetiology
Herpes Zoster
Clinical Picture
Symptoms No pain
vision (central ulcer)
Signs
Large deep ulcer perforation
Treatment
Usual ttt of corneal ulcer
Long term Bandage
Tarsorraphy ( median )

31. Traumatic Corneal ulcerTraumatic Corneal ulcer
Trauma + 2ry Infection
Trauma External: wounds, chemicals, burn & FB
Local: Lash, PTD & PTC

32. Degenerative ConditionsDegenerative Conditions
ARCUS SENELIS
Bilateral peripheral Fatty degeneration
Common in old age
Symptoms non
Signs
Clear zone between the opacity and Limbus (Lucid interval of vogt)
NB ARCUS JUVENILIS may occur in hyperlipidemia or juv. DM

33. Band Shaped keratopathyBand Shaped keratopathy
Horizonal opacity ( in the interpalpebral area )
Hyaline degeneration + Ca deposition

34. KERATOCONUSKERATOCONUS
 Definition
Progressive conical protrusion of the cornea
Starts at Puberty
Weakness of central part
 Incidence
Bilateral
+ve family history
 Symptoms
Gradual of vision - Myopia ( Curvature & Axial )
- irregular Astigmatism
- Opacity at the apex of the cone
Sudden of vision (Acute Hydrops i.e. acute edema due to rupture of DM)

35.  Signs of Keratoconus
A) Early
Retinoscopy ( RR is spinning or scissoring )
placido disc: ring distortion
Keratometer
B) Late
- Cone shaped central cornea
Notching of the L.L. on looking down Manson’
Slit Lamp Thin apex and deep A.C.
- Fleisher ring: brown ring the cone base ( hemosidren deposition )

36. KERATOGLOBUSKERATOGLOBUS
Congenital enlargement of the Anterior Segment
Signs
Cornea: Large in diameter and curvature
AC : Deep
Iris : Tremulous
Lens : Sublaxation

37. KERATOPLASTYKERATOPLASTY
 Aim: Replacing the opaque part by a clear cadaveric cornea
 Types:
- Lamellar ( Superficial )
- Deep ( Penetrating )
NB: Both of them may be partial or total
 Indications:
- Optical a) Central corneal opacities
b) Keratoconus
- Therapeutic a) Resistant corneal ulcer
b) Corneal fistula

40. Examination of
cornea reveals:
15-$1 Million
14-$500,000
13-$250,000
12-$125,000
11-$64,000
10-$32,000
9-$16,000
8-$8,000
7-$4,000
6-$2,000
5-$1,000
4-$500
3-$300
2-$200
1-$100
B-Anterior
staphyloma
C-Arcus senilis
D-Decematocele
A-Nebula
C-Arcus senilis

41. 15-$million
14-$500,000
13-$250,000
12-$125,000
11-$64,000
10-$32,000
9-$16,000
8-$8,000
7-$4,000
6-$2,000
5-$1,000
4-$500
3-$300
2-$200
1-$100
Examination of cornea reveals:
A-Nebula
B-Leucoma
C-Decematocele
D-
keratoconus
B-Leucoma

42. Examination of cornea reveals:
A-Nebula
B-Leucoma
adherent
C-Leucoma non-
adherent
D-
Keratectasia
15-$million
14-$500,000
13-$250,000
12-$125,000
11-$64,000
10-$32,000
9-$16,000
8-$8,000
7-$4,000
6-$2,000
5-$1,000
4-$500
3-$300
2-$200
1-$100
A-Nebula

44. Leucoma adherent

45. Keratoconus ‘Munson sign’
ccorneaccornea