eye banking by dr, nidhi thaker
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DR. NIDHI THAKER
• 1906: edumund zirm 1st successful corneal transplantation
• 1937: V P Filatow : father of modern eye banking • 1944: Dr. R. Townley Paton established
the first eye bank in New York City.• 1953: Stocker revealed the vital role
endothelial cells play in corneal transparency.
• 1955: Harris and Nordquist, published a paper that showed endothelium maintains function at 4°C.
• 1961: Eye Bank Association of America was established
• 1974: McKarey and Kaufman developed M-K medium which allowed the excised corneo-scleral rim to be preserved for up to 4 days at 4°C.
• 1985: Kaufman et al presented K-Sol as a storage method viable for up to 10 days.
What is an Eye Bank ?
IT IS A NON PROFIT COMMUNITY ORGANIZATION WHICH DEALS WITH THE COLLECTION , STORAGE , & DISTRIBUTION OF CORNEA FOR THE PURPOSE OF CORNEAL GRAFTING , RESEARCH & SUPPLY OF THE OTHER EYE TISSUES FOR THE OTHER PURPOSES
Functions of an Eye Bank :
Promotion
Registration
Tissue Retrieval
Tissue Processing
Tissue Evaluation
Serological Testing Tissue Distribution RESEARCH ACTIVITIES: • IMPROVEMENT IN PRESERVATION
METHODOLOGY• CORNEAL SUBSTITUTE• UTILIZATION OF THE OTHER COMPONENTS
OF THE EYE
Other uses:
• Donated Sclera can be used for glaucoma , oculoplastic and retinal surgeries
• Human amniotic membrane can be used for ocular surface procedures
• Fair and equitable distribution of transplantable tissues to corneal surgeons acco to waiting list.
STEPS OF EYE DONATION1. Donor selection2. Tissue retrival
3. Corneal examination4. Tissue transportation
5. Storage of corneal tissue6. Distribution
DONOR SELECTION1) AGE OF DONOR: no influence of age on tranplant
outcome.Older age : usage rate declinesLower limit : 2 yrs to prevent myopic shift
after keratoplasty
2) Medical history review
Eye banks must have consistent policies for the examination and documentation of donor's available
• medical records,• medical history• cause of death • Medications• laboratory reports
3) Legal consent taken from next of kin
consented donor meets medical and social history screening criteria
physical assessment reveals no contraindication to donation
acquisition of donor tissue can be carried out.
CONTRAINDICATION FOR THE USE OF DONOR TISSUE FOR KERATOPLASTY
1. Death of unknown cause 2. Death from central nervous system disease
of unestablished diagnosis 3. Creutzfelt-Jacob disease or a risk factor 4. Subacute sclerosing panencephalitis 5. Progressive multifocal
leukoencephalopathy 6. Congenital rubella
7. Reyes syndrome 8. Active viral encephalitis 9. Active septicemia 10. Active bacterial or fungal endocarditis 11. Active viral hepatitis 12. Rabies 13. Active leukemias 14. Active disseminated lymphomas 15. High risk for HIV infection 16. Hepatitis B surface antigen positive
17. HTLV-I or HTLV-II infection 18. Hepatitis C seropositive donors 19. HIV seropositive donors 22. Retinoblastoma, malignant tumors of the
anterior ocular segment 23. Active ocular inflammation 24. Congenital or acquired disorders of the
eye 25. Prior intraocular surgery or anterior
segment surgery
4) Serology testing5)Preperation of the donor povidone iodine 1- 5 % for 1-2 min + good stream of balanced saline
TISSUE RETRIVAL
enucleation i.e. surgical by in -situ removal of the whole eye corneo-scleral
excision (glob is retained In the orbit)
CORNEAL EVALUATION
Corneal evaluation• Examination of the corneas in situ• A simple penlight examination: 1. epithelial defects (drying, erosion, sloughing2. corneal edema with associated haze3. abnormal corneal shape4. blood or cloudiness in the anterior chamber5. corneal scars or infiltrates, arcus senilis, and
any signs of conjunctivitis and discharge.
• The slit-lamp examination:• Low power & higher power • Whole eyes can be examined within the
container used for the retrival• Excised cornea : from the bottom of the
storage vial• Cornea shd be allowd to reach the room
temp.
• A specular reflection of the endothelial layer can be observed in a small area of the endothelial reflex.
• The condition of the corneal endothelium is central to evaluating the suitability of corneal tissue for penetrating keratoplasty.
Methods of endothelial evaluation
• Specular microscopy : Mostly used by eye banks using hypothermic storage of corneo-scleral buttons.
• other methodS: 1. phase contrast microscopy 2.Transmitted light microscopy• critical density: 300-500 cells/mm3• Functional cell density: 1500-2200
cells/mm3
STORAGE METHODS
1)Moist chamber storage
• 1st described by Filatov• Sealed chamber with saline &
antimicrobial solution• Placed at 4▫ C• Disadv: corneal stromal edema & limited storage period ( up to 24
hrs)
Hypothermic corneal storage
• Mc carey and kaufman ; M K MEDIUM• Added dextran as an osmotic soln• Viability: 2-3 days• M – K FORMULATION : add HEPES as buffer & gentamicin &
phenol red Viability perid : 4 days
• K SOLUTION : M – K FORMULATION + 2.5% chondroitin suphate to extend the corneoscleral storage period
to up to 7 – 10 daysDisadv: corneal swelling
• DEXOL : + DEXTRAN TO K SOL
• OPTISOL : storage period max up to 14 days
OPTISOL GS: + GENTAMICIN & STREPTOMYCIN
Normothermic storage system
• Organ culture• Incubated at room temp in nutrient medium• Storage perid : 30 days• Glass bottle containing1. 100 ml of MEM medium 2.Earle’s salt soln3.2.5% fetal bovine serum
5. L – glutamine6. Antimicrobial agents cultured bottle is closed & icubated in dry
and at 31 - 37▫ C
Uses of Donated Eyes
Corneal Transplantation
Emergency Patching
Medical Education
Research
EYE BANK ORGANIZATION
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.
EBTC• . The top tier comprises of 5 Eye banking training centers (EBTC)
• responsible for1. tissue harvestin processing & distribution,2. creating public awareness 3. training and skill up-gradation of eye
banking personnel.
Eye banks• middle tier would comprise of a strong
network of 45 Eye Banks(EB)• These would cater to a population of 20
million each. These Eye Banks would be closely linked with 2,000 Eye Donation Centers- EDC (ratio of 1: 50 suggested), each of which would cater to a population ranging from 50,000 to 100,000.
EYE BANK PERSONNEL
1) EYE BANK INCHARGE:2) EYE BANK TECHNICIAN3) CLERK – CUM– STOREKEEPER4) MEDICAL SOCIAL WORKER /
PUBLIC RELATION OFFICER5) DRIVER -CUM - PROJECTIONIST
• 1. General supplies
a. Donor information sheet, consent forms, etc b. Pen-light—for gross examination of eyes c. Insulated container with water ice and special foam to
transport the tissue d. Supplies for blood collection e. Non sterile preparatory gloves f. Broad spectrum antibiotic solution g. Eye protection (safety goggles), shoe covers h. Disinfectant solution i. Eye caps/prosthesis j. Biohazard disposable bag k. Gauze and cotton pads Two small closed stainless containers for gauze pads
soaked in 70 percent alcohol in one and 5 percent betadine in the other.
• 2. Autoclaved and sterile materials:
a. A double holed drape b. Protective biohazard apparel-surgical gown
(preferably moisture impermeable) cap, mask, etc. c. Cotton tipped applicators or hemostats to open the
eyes. d. Sterile balanced salt solution or 0.9 percent sterile
saline to irrigate the eyes e. Two sterile hemostats . f. Sterile gloves. g. 8–10 pieces of gauze. h. Two eye jars with eye cages and a piece of 2" × 2"
gauze. Eye jars should be labeled left and right.
• 3. All instuments of enucleation procedure & For corneal excision (autoclaved)
• Blood samples are taken from the donor that is serologically tested for human immunodeficiency virus 1 and 2, Hepatitis B surface antigen and Hepatitis C virus.
EYE DONATION CENTERS
• Publicity of the volantary donation • Registration• Arrangement for the collection of the
eye after death• Processing , packing , & transportation of
collected eye to attached eye bank
The Present Scenario in Our Country
• Though the first eye bank in India was started as early as 1949 at Chennai, till the 90’s, our country had to depend on Sri Lanka for donor eyes.
Don't Burn or Bury
Your Eyes.....
Donate Them!
Blind Population1. World - 40 millions
2. India - 15 millions
3. Corneally Blind - 4.6 millions
• According to Indian Council of Medical Research (ICMR) 25% of the total blind in India are blind due to corneal blindness
Causes of Corneal Blindness
1. Infections
2. Injuries
3. Corneal Deteriorations following Eye Surgery
LEGAL ASPECTS IN INDIA• Under the Transplanta- tion of Human Organs Act,
1994 (THOA)1. The qualification of doctors permitted to perform
enucleation (surgi- cal eye removal) has been re- duced from MS (Ophth.) to MBBS.
2. Eye donation in India is always decided by the donor’s surviving relatives and not by the actual donor,
3. Enucleating doctors always have to legally obtain a written consent from the relatives of the deceased be- fore they actually remove the eyes.
Eye Donation
is Simple!
Removal of Eyes
takes 20 minutes only
Does not delay
funeral arrangements
Eye Balls
should be removed
within 6 hours after death
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