Eye donation Eye banking and Keratoplasty KHALIL

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GOOD AFTERNOON

WHAT DO ALL THESE PEOPLE HAVE

IN COMMON?

Lets find out…

EYE DONATION AND KERATOPLASTYPRESENTER: DR. KHALIL

MODERATOR: DR. CHARUDATT (M.S.)

• The EYE is wonderful creation

of nature and masterpiece of

perfection.

• And sight is one of

the most precious possessions.

• To lose vision – total or partial –

is a tragedy.

WONDERFUL EYE

CORNEAL BLINDNESS

• About 1.5 Million Indians suffer from Corneal Blindness

• Increasing at the rate of 30000 every year.

• Corneal blindness mainly affects children and young adults who have long life ahead of them.

IS THERE ENOUGH?

• On an average around 1 lakh corneas are needed in India every year.

ONLY about 15000 usable corneas are

collected every year.

We burn or we bury…

We Burn Or Bury

75 Lakh Pairs

Of Eyes……

1.5 Million EYES…

Leaving The 1.5 Million Corneal

Blind Persons To Live In Darkeness

WAITING FOR THE GIFT

Because of this huge shortfall of donor eyes in India there

is a long list of waiting patients.

EYE DONATION FORTNIGHT

Aug 25th – Sept 8th

CAUSES OF CORNEAL BLINDNESS

• Injuries

• Malnutrition

• Infections

• Chemical Burns

• Congenital Disorders

• Post operative complications

WHAT IS EYE DONATION?

• Only the cornea is used for transplant.

• Eyes should be donated within 6-8 hrs. of death.

• Total removal time is about 15-20 minutes.

• More than two Corneally blind persons can get sight due to a single person's eye donation

• Nobody is charged for making eye donation.

• The only cost to encounter is one local telephone call.

• It is replaced by artificial eyes to prevent

disfigurement

• The cornea is free of cost to the recipients

• The identity of both donor and recipient is kept secret

• It does not delay the funeral

LEGAL ASPECTS OF ORGAN

DONATION

Under the Transplantation of Human Organs Act, 1994 (THOA)

• The qualification of doctors permitted to perform enucleation (surgical eye removal) has been reduced from MS (Ophth.) to MBBS

• Eye donation in India is always decided by the donor’s surviving relatives and not by the actual donor,

• Enucleating doctors always have to legally obtain a written consent from the relatives of the deceased before they actually remove the eyes.

• Any Gender can donate eyes

• All religions endorse the practice of eye donation

• Willing donation of one’s own eye during life

• Eyes from medico legal post mortem cases

• Eyes from unclaimed bodies

• A good donor cornea

• Healthy cornea

• Removal of cornea soon after death (within 6 hrs)

WHO CAN DONATE EYES?

HOW TO DONATE EYES?

• Donation can happen in either of these ways:

1. S/He can walk Eye Bank and PLEDGE their eyes for donation pledge form signed by a witness given back to the eye bank.

• In the time of that person’s death, his/her relative/friend, who was a witness should call the nearest eye bank.

• Donors relatives and friends should be well informed and be well aware to call the nearest eye bank, for donating the eyes after their death.

2. After death, a relative or a friend of the deceased person can inform the eye bank and tell them that they wish to donate the eyes of their bereaved folk.

Age/Sex - NO BAR for Eye Donation

MYTHS ABOUT EYE DONATION

• Face/ Body will be disfigured.

• Will be born blind in next birth.

• Will not be able to see GOD.

WHAT IS

NEEDED?

1. GENERAL SUPPLIES

a. Donor information sheet, consent forms, etcb. Torch for gross examination of eyes c. Insulated container with water ice and special foam to

transport the tissue

d. Supplies for blood collectione. Non sterile gloves f. Broad spectrum antibiotic solution

g. Eye protection (safety goggles), shoe coversh. Disinfectant solutioni. Eye caps/prosthesis

j. Biohazard disposable bagk. Gauze and cotton pads

2. AUTOCLAVED AND STERILE MATERIALS

• A double holed drape • Surgical gown (preferably moisture impermeable) cap,

mask, etc.• Sterile balanced salt solution or 0.9 percent sterile

saline to irrigate the eyes• Two sterile hemostats .• Sterile gloves• 8–10 pieces of gauze.• Two eye jars with eye cages and a piece of 2" × 2"

gauze. Eye jars should be labeled left and right.

3. EQUIPMENT FOR ENUCLEATION

The following equipment is required for enucleation

• Eye speculum;

• Muscle hook;

• Haemostat

• Enucleation spoon

• Sharp dissecting scissors;

• Forceps

• Large curved scissors (non-pointed);

• Metal bowl

• Cotton tip

• 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.

ENUCLEATION PROCEDURE

AFTER DONATION

• The donor’s family receive a certificate of appreciation from the Eye Bank.

• Eyes are evaluated at the Eye Bank and only the ones deemed suitable are used for transplant. Others are used for research and education.

• Recipients are notified on a first come first serve basis from the registry.

GRADING OF GRAFT CLARITY(R.P. CENTRE GRADING SYSTEM)

4+ : Graft absolutely clear; all details of AC and iris visible

3+ : Graft clear but some details of iris and AC obscured.

2+ : Graft hazy;iris and AC visible but no details discernible.

1+ : Graft very hazy; iris and AC just visible.

0 : Graft opaque

CONTRAINDICATIONS FOR USE OF DONOR TISSUE

Systemic Causes :

• Death of unknown cause

• Death from CNS disease of unestablished diagnosis

• Creutzfeldt-jacob disease or risk factor

• Subacute sclerosing panencephalitis

• Progressive multifocal leukoencephalopathy ,hepatitis-c seropositive donors

• HTLV-1 or HTLV II infection

• HIV

• Active leukemia

• Septicemia

• Active disseminated lymphomas

OCULAR CAUSES

• Intrinsic eye disease

• Retinoblastoma

• Malignant tumors of the anterior segment

• Active ocular or intra ocular inflammation

• Prior intra ocular surgery or anterior segment surgery

• Refractive corneal procedures

• Laser photo ablation surgery

STORAGE OF DONOR GRAFT TISSUE

Many methods of corneal preservation have

been proposed.

• Short term storage (24 to 96 hours)

• Intermediate term storage (up to 2 weeks)

• Long term preservation (up to 4 weeks)

• Very long term preservation (>4 weeks).

SHORT TERM STORAGE-

Moist chamber storage

• Enucleated eye in a sealed chamber together withgauze, usually moistened by glycerine placed at40c.

• Storage time 24 hours

INTERMEDIATE-TERM STORAGE-

• In the intermediate-term corneal storage, as in the M-K medium storage, excised corneoscleralbuttons are kept in biochemically defined tissue culture medium

• They are incubated at 4°C e.g. Chondroitin sulfate storage medium (CSM), dexsol, optisoland likorol, storage time 7 to 14 days.

LONG-TERM CORNEAL STORAGE

The organ culture method of cornea.

Human cornea stored at 34°C for at least five weeks.

VERY LONG-TERM CORNEAL STORAGE

• Cryopreservation of the Cornea

• Stored at –160C

• preservation of donor cornea for periods up to one year

OPTIMAL PERIOD TO MAINTAIN CORENAL ENDOTHELIAL VIABILITY

MEDIUM OPTIMAL TIME• Moist chamber 24 hrs.• MK 72 hrs.• CPTES Solution 72 hrs.• EP II 96 hrs.• RPC (Modified M-K) 96 hrs.• Dexol 1 wk• Likorol 1 wk• Optisol 1 wk• Organ culture 4-5 wks.• Cryopreservation 1 year on more

WHAT IS AN EYE BANK?

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

KERATOPLASTY

• Abnormal corneal host tissue is replaced by healthy donor cornea.

• Corneal transplantation remains

the main method for visual

rehabilitation once disease has

affected corneal clarity.

• Corneal transplantation remains to this day one of the most successful and most often performed human transplants (after blood transfusions and bone grafts).

Replacement of diseased cornea with donated healthy cornea.

HISTORY

• The first successful human corneal transplant was a lamellar keratoplasty performed by von Hippel in 1888 using rabbit donor tissue.

• Eduard Zirm who did the first successful full thickness penetrating keratoplasty in 1905.

• Spanish-born eye surgeon Ramon Castroviejo successfully performed keratoplasty as early as 1936.

• 1950, Jose Barraquer and colleagues in Colombia applied new techniques of lamellar keratoplasty by dissecting the corneal stroma down to two-thirds of its thickness in both the donor and the recipient tissue.

INDICATIONS

OPTICAL

• Psuedophakic bullous keratopathy

• Keratoconus

• Corneal dystrophies and degenerations

• Corneal scarring

TECTONIC

• Stromal thinning

• Descemetocele

• Perforated cornea

THERAPEUTIC

• Inflammations not responding to medical therapy.

COSMETIC

TECHNIQUE

• PREOPRATIVE EVALUATION

• PREPARATION OF RECIPIENT

• DONOR PREPARATION

• HOST TREPHINATION

• SUTURING

PREOPERATIVE EVALUATION

• Comprehensive ophthalmic evaluation- B- scan, and OCT or ultrasound biomicroscopy to asses visual potential.

• Ocular surface abnormalities must be recognized and treated prior to penetrating keratoplasty. These include rosacea, dry eyes, blepharitis, trichiasis, exposure keratopathy, ectropion, and entropion.

• Intraocular pressure (IOP) must be controlled prior to surgery.

• Ocular inflammation – must be recognized and treated,

• Prior corneal diseases and vascularization – History of herpetic keratitis significantly reduces the chance of graft success.

• Corneal thinning and melting, such as that associated with rheumatoid arthritis, may significantly affect the surgical outcome of penetrating keratoplasty and thus must be treated adequately prior to the surgery.

PREPARATION OF RECIPIENT

• Scleral support rings applied tofix the globe

• The recipient cornea measuredwith a caliper.

• Radial marks to guide sutureplacement may be made using a gentian-violet stained 8-bladeradial marker

• Trephination

DONOR PREPARATION

• Rinsing the globe in a dilute povidine-iodine solution (10% solution diluted 1:10 with balanced saline solution) for 1-2 minutes.

• Followed by a thorough rinse with a balanced saline solution.

CORNEO-SCLERAL BUTTON REMOVAL

DONOR TISSUE EVALUATION

• Gross in situ evaluation

• Slit lamp evaluation

• Specular microscopy

Gross examination

• The corneal-scleral segment shall be initially examined grossly for clarity, epithelial defects,foreign objects and contamination and scleral color. e.g., jaundice.

• Enucleated globes shall be examined in the laboratory prior to distribution and/or corneal excision.

Slit-lamp examination

• Examined for epithelia and stromal pathology and in particular endothelial disease.

• After corneal excision, the corneal-scleral rim shall be evaluated by slit lamp biomicroscopy, even if the donor eye has been examined with the slit lamp prior to excision of the cornealscleralrim, to ensure that damage to the corneal endothelium or surgical detachment of Descemet’s membrane did not occur.

SPECULAR MICROSCOPY

For transplantation cell count should be at least 1500 cells/sq mm.

SEROLOGY

• The 5cc of blood collected from the donor is tested for

• Human Immuno Deficiency virus (AIDS)

• Hepatits B and C

Syphilis etc .

SUTURING

• The graft is secured onto therecipient bed by four or heightinterrupted 10-0 nylon cardinal

sutures equally spaced apart.

• The first cardinal suture is placed at the 12 o’clock position, The second and most important cardinal suture is placed 180° opposite inferiorly.

• Remaining sutures are applied.

TYPES OF CORNEAL TRANSPLANTS

• Penetrating keratoplasty (PK)

• Lamellar keratoplasty (LK) –

• Anterior lamellar keratoplasty (ALK)

• Deep anterior lamellar keratoplasty(DALK)

• Posterior lamellar keratoplasty (PLK)/

Endothelial keratoplasty (EK) • Descemet’s stripping endothelial

keratoplasty (DSEK)• Descemet membrane endothelial

keratoplasty (DMEK)

PENETRATING KERATOPLASTY (PK)

Indications

1 Combined endothelial and stromal disease (Fuchs’ dystrophy with corneal ectasia or macular stromal dystrophy).

2 Severe corneal opacification and inability to ascertain the status of the endothelium .

3 Keratoconus after hydrops with tears in Descemet’s membrane; successful deep anterior lamellar keratoplasty is unlikely.

4 Other causes of corneal opacification and lack of familiarity with selective keratoplasty techniques.

Contraindications

1 Epithelial dysfunction secondary to limbal stem cell deficiency (aniridia, chemical injuries), severe neurotrophic, and dry eye states.

2 Stromal vascularization, especially when involving more than two quadrants.

3 Multiple (two or more) graft failures.

Advantages

1 Can be used for any indication (stromal or endothelial).

2 Relatively easy surgery as compared to other techniques.

3 No lamellar – corneal interface problem thus good visual

results.

Disadvantages1 Lengthy postoperative course.

2 Incidence of allograft rejection (10% to greater than 90%, depending on the indication.

3 Suture complications: exposure, vascularization, and infection.

4 Weak graft–host junction: risk of traumatic wound dehiscence and globe rupture.

5 Unpredictability of corneal toricity and degree of ametropia.

INTRAOPERATIVE COMPLICATIONS

• Scleral perforation with fixation sutures

• Improper trephination

• Damaged donor button

• Retained Descemet's membrane

• Iris–lens damage

• Anterior chamber haemorrhage

POSTOPERATIVE COMPLICATIONS

• Wound leak

• Flat anterior chamber with

increased intraocular pressure

• Endophthalmitis

• Persistent epithelial defect

• Primary graft failure

• Suture related.

• Graft rejection

LAMELLAR KERATOPLASTY

Partial thickness graft of donor tissue is used.

LAMELLAR KERATOPLASTY

PLK/EKALK

DALK DMEKDSEKSALK

ANTERIOR LAMELLAR KERATOPLASTY

Indications

• Indicated for corneal pathologies affecting the anterior 85–95% of the cornea, sparing Descemet's membrane and endothelium

• Superficial corneal opacities,

Previous refractive surgical procedures,

Infections, trauma or degenerations and dystrophies.

DEEP ANTERIOR LAMELLAR KERATOPLASTY

• Anterior layers of the central cornea are removed and replaced with donor tissue. Endothelial cells and Descemets membrane are left in place.

USED IN

• Anterior corneal opacifications,

• Scars

• Ectatic diseases such as keratoconus.

LAMELLAR DISSECTION TECHNIQUES

• Manual dissection

• Air bubble technique

• Microkeratome

• Femtosecond laser

CONTRAINDICATIONS OF ALK

• Absolute:

• Endothelial dysfunction

• Posterior dystrophies (Fuchs’, posterior

polymorphous)

• Pseudophakic and aphakic bullous keratopathy

• Nonguttate endothelial dystrophy

• Iridocorneal endothelial syndrome

Relative:

• Epithelial dysfunction , Limbal stem cell deficiency states (aniridia, chemical injuries, etc.)

• Chronic surface disease (keratoconjunctivitis sicca, neurotrophic keratitis, and others)

ADVANTAGES

1 Preservation of host endothelium

2 Eliminates endothelial graft failure decreases the incidence of allograft rejection

3 Allows for the incorporation of more diseased stromal tissue

includes entire ectatic area (ideal in keratoconus) Minimize suture/wound-induce astigmatism

4 Avoids posterior pressure and is associated with a lower incidence of suprachoroidal haemorrhage.

DISADVANTAGES

1 Surgical difficulty

2 Optical effect of interface, which decreases the more posterior the location of the lamellar dissection

POSTERIOR LAMELLAR KERATOPLASTY

Indications • Posterior corneal dystrophies (Fuchs’, nonguttate

endothelial dystrophy, posterior polymorphous)

• Aphakic and pseudophakic corneal edema and bullous keratopathy

• Iridocorneal endothelial syndrome (ICE)

• Other causes of endothelial dysfunction (trauma, foreign body, age, etc.)

Contraindications

• Corneal ectasias.

• Stromal dystrophies

• Stromal scarring or opacification (infection, interstitial keratitis, lipid keratopathy, etc.)

• Anterior corneal dystrophies and degenerations (Reis- Bücklers, Salzmann's, Meesmann's, etc.)

Advantages• Rapid visual rehabilitation

• No suture-related complications

• Decreased incidence of allograft rejection

• Intact globe, resistant to traumatic wound dehiscence

• Predictable corneal toricity, minimal topographic change

• Predictable, small hyperopic refractive shift .

Disadvantages

• Steep learning curve for surgeons, and the placement of the donor tissue can be difficult.

• Handling the tissue gently is imperative because excessive manipulation can result in loss of endothelial cells, leading ultimately to loss of graft clarity, which is the principal cause of failed DSAEK

• Positioning of the air bubble

• Postoperative hyperopic shift in their refractive error.

• Endothelial rejection can occur and should be treated promptly with high dose steroids.

DESCEMET'S STRIPPING AUTOMATED ENDOTHELIAL KERATOPLASTY (DSAEK)

Surgical steps

Stripping the diseased endothelial surface and removing it, which is performed through a corneal limbal incision or scleral tunnel.

A posterior donor button includes endothelium, Descemet's membrane, and stroma, with a resulting thickness of 100 microns.

The donor tissue is folded to enter the wound and is then positioned to match up with the recipient's eye.

An air bubble is then positioned to temporarily secure the interface attachment. The pumping action of the endothelial cells helps the donor tissue permanently stick into place and position.

DESCEMET MEMBRANE ENDOTHELIAL

KERATOPLASTY (DMEK)

• This endothelial keratoplasty is similar to DSAEK except that with DMEK the donor tissue is comprised of Descemet's/endothelial complex and does not have any attached central stromal tissue.

• The result of a thinner donor profile is that it improves the patient's visual potential and decreases the trend towards hyperopia as compared to DSAEK.

AFTERCARE• Often performed on an outpatient basis,

although some patients need brief

hospitalization after surgery.

• Patient will wear an eye patch at least

overnight. An eye shield or glasses must be

worn to protect the eye until the surgical

wound has healed.

• Eye drops will be prescribed for the patient to use for several weeks/yearsafter surgery.

• Drops - antibiotics to prevent infection, corticosteroids to reduce inflammation and prevent graft rejection.

CARRY HOME MESSAGE

Why destroy a gift ? Donate

ARE YOU READY TO BECOME A SIGHT AMBASSADOR….

TO SUPPORT THE EYE DONATION MOVEMENT?

"There is no lovelier way to

thank God for your sight than

by giving a helping hand to

those in the dark."

- Helen Keller

THANK YOU

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