Endothelial Keratoplasty DSAEKting from the Inside

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Endothelial Keratoplasty DSAEK-ting from the
Inside

• Paul Phillips M.D.
• Sightline Laser and Ophthalmic Associates
• University of Virginia Dept of Ophthalmology

Humphries Tech Lecture 9-12-09
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Goals of EK Talk

• Discuss normal physiology of endothlium and
  endothelial failure
• Historical perspective
• Briefly discuss the development of endothelial
  keratoplasty
• Discuss techniques of DSAEK in more detail
• Discuss outcomes and normal post-operative
  course.

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Healthy Eye With Normal Endothelial Cell Function
Epithelial Cell Layer
Stroma
Cornea
Endothelial Cell Layer
Crystalen Lens (Cataract)
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Diseased Endothelium from Fuchs Dystrophy
Resulting in Microcystic Corneal Edema
Epithelial Cell Layer
Microcystic edema
Stroma edema
Cornea
Endothelial Cell Layer
Crystalen Lens (Cataract)
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Corneal Transplantation
Could not a small piece of cornea be excised
with a trephine, the size of a small bristle or a
large quill and would it not heal with a
transparent scar? - 1760 - Erasmus Darwin

1731-1802

• Corneal transplantation has been used to treat
  corneal disease for over 100 years.
• The first successful full thickness human
  transplant performed by a private practice
  physician, Eduard Zirm, in 1905.1,2

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Over 50 of corneal transplants in the United
States are performed primarily to treat
endothelial dysfunction.
Endothelium
(Eye Bank Association of America, Statistical
Report, 2005)
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Penetrating Keratoplasty
Trephination cuts
B
A
Open eye post trephination
D
C
Donor cornea with healthy endothelium trephine
The donor is sutured into area of central
trephination
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PK Surgery Full Thickness Surgery
Donor tissue sutured into recipient
Recipient tissue removed
Central trephine cut made
Sutures create an irregular surface with
astigmatism and blurring
Full thickness block of tissue removed just to
get to the endothelium
Smooth Surface with only endothelial disease
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Optically purebut often high astigmatism

• Beautifully clear graft, 20/20 vision, minimal
  astigmatism.
• After sutures out at one year, vision is still
  20/20, but
• MR -3.00-5.00X16020/20

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Additional Problems Associated with PKs

• Suture related problems
• Immune reactions
• Suture infiltrates/Ulcerations
• Rejection episodes
• Infections
• Wound integrity related problems
• Early and Late wound dehiscence
• Mild trauma leads to rupture even years after PK

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Suture related complications
Pt. 1

• Patient 1 Exposed suture 1 ½ years after PK
  leading to ulceration and rejection episode

Pt. 2

• Patient 2 Endophthalmitis from retained suture
  fragment 2 years after PK

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Wound integrity related complications
Pt. 1

• Patient 1 Expulsive Hemorrhage From mild
  blunt trauma five years after PK

Pt. 2

• Patient 2 Rupture with vitreous loss 3 years
  after PK. Fell at home (blunt trauma).

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Solution to Problems with P.K.

• Eliminate corneal sutures
• No suture problems
• Eliminate corneal surface incisions
• Faster wound healing, smoother topography,
  stronger and more stable eye.

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Endothelial Keratoplasty

• The selective transplantation of the endothelium
• Multiple names and acronyms for small changes
• PLK Posterior Lamellar Keratoplasty (Melles,
  1999)
• DLEK Deep Lamellar Endothelial Keratoplasty
  (Terry, 2001)
• DSEK Descemets Stripping Endothelial
  Keratoplasty (Price, 2005)
• DSAEK Descemets Stripping with Automated
  Endothelial Keratoplasty (Gorovoy, 2006)
• DMEK Descemets Membrane Endothelial
  Keratoplasty (Melles, 2006)

Case report only, has not been validated in a
larger study.
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Deep Lamellar Endothelial KeratoplastyDLEK
Recipient tissue removed
Scleral incision, deep corneal pocket, and
endothelium trephined with Terry Trephine or
cut with Cindy Scissors
Endothelium removed with posterior stromal disc
Donor tissue placed into recipient
Endothelium replaced with no sutures, supported
by air bubble in anterior chamber. Surface
remains smooth with no astigmatism
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DSAEK Surgery
A
B
Sick endothelium
Incision
Donor Cornea
5mm Incision Made
Diseased descemets stripped
D
Cornea clears as it is thinned by the new
endothelium
Graft held in position with air bubble
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DSAEK for Fuchs Dystrophy
The new endothelium of the DSAEK graft rapidly
deterges the stroma as demonstrated here by OCT
of the anterior segment preoperatively and at
days 1 and 5 days postoperatively.
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Complications
725 DSAEK case performed at Devers Eye Institute
as of 8/1/09
Dislocations in DSAEK (N19)
2.6
Primary Graft Failure in DSAEK (N1)

• 0.1

Pupillary Block in DSAEK (N1)
0.1
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DSAEK Visual Results Prospective study, 6 months
post-op (n100)

• Visual acuity (mean BSCVA)
• All eyes (n100) 20/38
• Eyes without measurable retinal disease (n74)
  20/30
• Percent of eyes 20/40 (or better) 97
• Percent of eyes 20/25 (or better) 38
• Percent of eyes 20/20 (or better) 14

Chen, Terry, Shamie, et al Cornea 2007
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DSAEK Current Results (July 2007) Prospective
study, 1 year post-op (n 100)

• Astigmatism Less than 0.06 D change from pre-op
  measurements (p.68)

Terry MA, et al. Endothelial survival following
DSAEK surgery in a large prospective study.
(Terry et al Ophthalmology, 2007, in press)
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Typical Post Operative Course

• Visits
• Day 1, Week 1, Month 1, Q2-3 months and Year 1.
• If no steroids, Q6 months
• If steroids are continued, Q3 month visits for
  second year can be tapered to Q4-6 month visits
  the following year.
• Immediate Post op
• Eye patched and shielded
• Supine positioning for 1 hour followed by supine
  positioning at all times except bathroom use and
  to eat.
• Pain meds (rarely needed)

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Typical Post Operative Course

• Post Op Day 1
• Patch removed.
• Vision is usually between finger counting and
  20/80
• IOP check only if complaints of pain or signs of
  microcystic edema (signs of increase iop) (avoid
  trauma to graft if possible)
• Slit Lamp Exam
• Wound check
• Surface (if significant epi defect, bandage
  contact lens placed)
• Graft Position (Attached/Detached?
  Centered/Decentered?)
• Signs of interface fluid (if localized, will
  resolve)
• AC reaction
• IOL position (especially if triple procedure or
  IOL exchange)

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Typical Post Operative Course

• POD 1 continued
• Patient instructed on meds
• Prednisolone 1 QID (tapered over course of
  12molonger if necessary)
• Flouroquinolone QID
• Topical NSAID (If triple procedure or IOL
  exchange)
• Lubricating ointment QHS
• Patient activity instructions
• NO RUBBING, NO RUBBING, NO RUBBING!
• Supine positioning 2 hours every 2 hours for
  entire day.
• Sleep with eye shield for two weeks

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Typical Post Operative Course

• POD1 continued
• Warning signs discussed
• Usual signs of infection (redness, pain,
  discharge, photophobia, decreased vision)
• Signs of dislocation Painless dramatic drop in
  vision
• Patient is instructed to call (but not to panic)
• Repositioning or rebubbling can take place in a
  non-emergent fashion within 1-2 weeks.
• At Devers most dislocation occurred at
  POD1-POD4 and have not occurred later than 1
  week.
• Week 1
• Vision improves 20/100-20/40
• Patient begin to realize benefit (many begin to
  inquire about surgery on their other eye
• Check Wound, IOP, Surface, Interface (fluid
  usually resolved if present on POD1)
• If vision slow to recover, encourage patient
  (significant variability in vision at this time)
• Continue meds

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Typical Post Operative Course

• Month 1
• Vision 20/60-20/20
• Refract if patient anxious to improve vision
  (advise patient that change in refraction may
  occur)
• Full exam, consider dilation especially if
  triple or other combined procedure or if VA
  lower than expected
• Patient advised on signs of rejection RSVP
• Redness, Sensitivity to light, Vision decrease,
  Pain
• Subsequent follow up as noted above
• Refraction generally stable at 2-3 months
• While on Steroids, IOP checks are imperative
• Steroid response usually does not occur within
  first few weeks, but can occur at any time there
  after.
• If steroid response, we first add IOP lowering
  meds or consider SLT/LTP, if no improvement,
  decrease steroid dose or strength.

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Thank You.