OPHTHALMOLOGY

1. Eye bank

2. Eye Bank is a non profit organization
which deals with the collection, storage
and distribution of the donor cornea for
the purpose of corneal grafting, research
and supply of eye tissues to other eye
banks for ophthalmic purposes.

3. THREE TIER ORGANIZATION
An integrated system involving a
three-tier community eye
banking pyramid based on the
infrastructure and manpower at
all levels
• The three tiers proposed were
eye donation centres, eye bank
and eye bank training centres

4. EDC - Eye Donation Centers
• affiliated to a registered eye bank
(1) public and professional awareness about eye donation
(2) co-ordinate with donor families and hospitals to motivate eye
donation
(3) to harvest corneal tissue and collect blood for serology
(4) to ensure safe transportation of tissue to the parent eye bank.

5. Eye banks
• Middle tier comprise of a strong network of 45 Eye
Banks(EB)
• These Eye Banks are closely linked with 2,000 Eye
Donation Centers- EDC, each of which would cater to a
population ranging from 50,000 to 100,000.

6. • Provide a round-the-clock public response system over the telephone
and conduct public awareness programs on eye donation.
• Co-ordinate with donor families and hospitals to motivate eye
donation/Hospital Cornea Retrieval Programs – (HCRP)
• To harvest corneal tissue
• To process, preserve and evaluate the collected tissue
• To distribute tissue in an equitable manner for Keratoplasty
• To ensure safe transportation of tissue

7. EBTC- Eye banking training center
• The top tier comprises of 5 Eye banking training centers
(EBTC)
• All of the eye bank functions plus training for all levels of personnel in
eye banking and research.

8. Functions of an Eye Bank
 Promotion
 Registration
 Tissue Retrieval
 Tissue Processing
 Tissue Evaluation

9. Eye Bank
Tissue
Harvesting
Tissue
Distribution
Tissue
Evaluation
Tissue
Preservation
Public
Awareness
Research

10. Contraindications
• Systemic:
• AIDS
• Rabies
• Active viral hepatitis
• Creutzfeldt-Jakob disease
• Reye’s syndrome
• Death from unknown causes
• Congenital Rubella
• Active septicemia
• Leukemia (blast form)
• Lymphoma/lymphosarcoma

11. • Ocular:
• Intrinsic eye diseases
Retinoblastoma
Active conjuctivitis,iritis,uveitis,vitritis,retinitis
Congenital abnormalities (keratoconus)
Central opacities,pterygium
• Prior refractive procedures (radial keratotomy)

12. How It Works ?
Recovery
or retrieval
Cornea
Processing
Distribution

13. STEPS OF EYE DONATION
1. Donor selection
2. Tissue retrival
3. Corneal examination
4. Tissue transportation
5. Storage of corneal tissueDistribution

14. Preliminary preparations
• Obtain legal permission.
• Go through the donor’s medical records for any contraindications.
• Wash hands and be prepared with aseptic dressing.
• Identify the donor.
• Collection of postmortem blood:10ml
Femoral vein
Subclavian vein
Heart
Jugular vein

15. Enucleation

17. Corneo-scleral button excision

19. Serological testing
• HIV
• HBV
• HCV
• Syphilis

20. Storage of donor tissue
Storage
Short term
2-3days
Moist chamber
(24hrs)
M-K medium
Intermediate
7-10days
K-sol,
Dexsol,Optisol,
Optisol GS
Long term
30days
Organ culture
medium,
MEM
Very long term
1year
Cryopreservation

21. Moist chamber storage
• Whole globe in a sealed container
• 4 degree C
• Advantages
• Simple, minimum manipulation
• Disadvantage – time limit only 48 hours

22. M-K medium
Described by Mc-Carey & Kauffman.
• Mixture of tissue culture medium and Dextran (5%,40,000 MW)
• Buffer
• Antibiotics:Penicillin,Gentamicin,Polymyxin
• Storage period- 96hrs.

23. K-Sol
• Purified chondroitin sulphate in tissue culture medium.
• Storage:7-10days in 40 C

24. Cornea storage Media Storage time (days)
MK 4
K-SOL 7
CSM 7
DEXSOL 10
OPTISOL 14
PROCELL 14

25. Long term Organ Culture storage system
ORGAN CULTURE METHOD
• Upto 35 days
• Earle’s salts without L- glutamine
• L- glutamine
• Decomplemented calf serum
• 1.5% chondroitin sulfate

26. MEM media(minimum essential media)
Developed by Harry Eagle.
34 degree C
Incubated at room temperature in nutrient medium
Storage period : 30 days
Advantage: Enables HLA matching

27. Very long time preservation
CRYOPRESERVATION
Corneal rim is passed through a series of solutions containing increasing
concentration of dimethyl sulfoxide (DMSO) upto 7.5%
• Tissue frozen at controlled rate upto -80 deg C
• Stored indefinitely at -160 deg C
• Not popular
• Disadvantages
• Expensive
• Highly trained technical persons needed
• Slight error can lead to tissue damage

28. Assessment of Donor Tissue
• Slit lamp examination eyeball
• Corneal button by specular microscope

29.  Corneal epithelium
microcystic edema, epithelial defects
 Corneal stroma
opacities, infiltrates, edema, DM folds
 Endothelium
Guttata, snail track marks (stress fractures of
endothelium)
 Anterior chamber – any crystals

30. Specular microscopy
 Edothelial cell density - < 1500cells/mm
 Severe polymegathism or pleomarphism
 Presence of cornea guttata
 Abnormally shaped endothelial cells –fused cells
 Abnormal single cell defects
 Severe edema of endothelium
 Presence of inflammatory cells on endothelium

31. GRADING OF TISSUE
EXCELLENT
No epithelial defect
No arcus senilis
No folds in DM
Excellent
endothelium – no
defects
POOR
• Vacuolated cells
• Severe stromal
cloudiness
• Marked folds
• Endothelium-
marked defects,
low cell density,
central vacuolated
cells

32. CORNEA GRADING
-EXCELLENT
-VERY GOOD
-GOOD
-FAIR
-NSFS (NOT SUITABLE FOR SURGERY)

33. • NSFS (Not Suitable For Surgery)
For Training and
Research