Download Hemi–Descemet Membrane Endothelial Keratoplasty

Research
Brief Report
Hemi–Descemet Membrane Endothelial Keratoplasty
Transplantation
A Potential Method for Increasing the Pool
of Endothelial Graft Tissue
Fook Chang Lam, MRCP, FRCOphth; Lamis Baydoun, MD; Martin Dirisamer, MD; Jessica Lie, PhD;
Isabel Dapena, MD, PhD; Gerrit R. J. Melles, MD, PhD
IMPORTANCE This study evaluates the technical feasibility and clinical outcomes of a
Descemet membrane endothelial keratoplasty (DMEK) technique that could increase the
availability of donor tissue for DMEK.
OBJECTIVE To evaluate the clinical outcome of using a semicircular, large-diameter Descemet
membrane graft in DMEK (hemi-DMEK), potentially allowing the use of a single donor cornea
for 2 DMEK procedures.
DESIGN, SETTING, AND PARTICIPANTS A prospective, interventional case series was conducted
at a tertiary referral center. Three eyes of 3 patients with Fuchs endothelial dystrophy
received a hemi-DMEK.
INTERVENTION Transplantation of a semicircular, large-diameter hemi-DMEK graft.
MAIN OUTCOMES AND MEASURES Best-corrected visual acuity, endothelial cell density,
pachymetry, and intraoperative and postoperative complications.
RESULTS The patients’ best-corrected visual acuity at 6 months was 0.70 (Snellen equivalent,
20/29), 0.50 (20/40 [amblyopic eye]), and 1.20 (20/17). At 1 month, endothelial cell density
decreased by 49%, 31%, and 39%, respectively, and endothelial cell migration appeared to
continue for up to 6 months. Central corneal thicknesses decreased from 682, 707, and 681
μm before surgery to 523, 534, and 489 μm, respectively, at 6 months. No intraoperative or
postoperative complications were seen.
CONCLUSIONS AND RELEVANCE Hemi-DMEK (using half-moon–shaped grafts) is technically
feasible and may provide visual outcomes similar to those obtained with routine DMEK
(full-moon–shaped graft). If so, this technique may have the potential to double the
availability of donor endothelial tissue for DMEK surgery.
Author Affiliations: Netherlands
Institute for Innovative Ocular
Surgery, Rotterdam, the Netherlands
(Lam, Baydoun, Dirisamer, Lie,
Dapena, Melles); Melles Cornea Clinic
Rotterdam, Rotterdam, the
Netherlands (Lam, Baydoun,
Dirisamer, Dapena, Melles);
Allgemeines Krankenhaus Linz, Linz,
Austria (Dirisamer); Amnitrans
EyeBank Rotterdam, Rotterdam,
the Netherlands (Lie, Melles).
JAMA Ophthalmol. doi:10.1001/jamaophthalmol.2014.3328
Published online September 11, 2014.
Corresponding Author: Gerrit R. J.
Melles, MD, PhD, Netherlands
Institute for Innovative Ocular
Surgery, Laan op Zuid 88, Rotterdam,
Zuid-Holland 3071 AA,
the Netherlands
([email protected]).
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Research Brief Report
Hemi–Descemet Membrane Endothelial Keratoplasty
I
n the past dec ade, endothelial keratoplasty (EK)
may have become the preferred treatment in corneal
endothelial dysfunction, and the latest refinement
of the procedure, Descemet membrane EK (DMEK), may
provide the best and fastest visual recovery. 1-3 There is,
however, a significant shortage of donor corneal tissue in
many parts of the world.4,5 This shortage may be lessened
by the use of split donor tissue for DMEK and deep anterior
lamellar keratoplasty. 6-8 However, the use of split donor
tissue does not solve the increasing demand for endothelial
grafts.
Currently, only the central portion of the Descemete n d o t h e l i a l c o m p l ex (8. 5 - t o 9. 5 - m m d i a m e t e r ) i s
harvested; the peripheral rim (ie, approximately half
of the graft surf ace area) is disc arded. In contrast
to penetrating keratoplasty and Descemet stripping
(automated) EK, there is no optic al or technic al
reason to use only the central portion of the donor tissue in
DMEK, since a DMEK graft is very thin and uniform
in thickness. The aim of the present study was to explore
the feasibility and describe the clinical outcomes of harvesting and transplanting a half-moon (semicircular) hemiDMEK graft.
Methods
Dutch Medisch Ethische Toetsingscommissie provided
institutional review board approval, and all patients provided written informed consent. The study was conducted
according to the Declaration of Helsinki. The participants
did not receive financial compensation.
Three pseudophakic eyes of 3 women (aged 66, 72, and
65 years) underwent hemi-DMEK surgery for decompensated Fuchs endothelial dystrophy. One patient was
amblyopic in the operated eye.
Donors
Corneoscleral buttons were excised from donor globes (donor ages 49, 70, and 67 years) obtained less than 36 hours
Figure 1. Surgical Images of Preparing a Hemi–Descemet Membrane (DM) Endothelial Keratoplasty Graft
A DM loosened from the scleral spur
B
C
D DM roll forms after immersion in saline
DM completely stripped from the posterior stroma
A, The corneoscleral rim was mounted endothelial side up on a custom-made
holder, and the DM was then loosened with a hockey stick knife from the scleral
spur in a central direction. B, The corneoscleral rim was divided into 2 equal
halves. C, The DM was then completely stripped from the posterior stroma to
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Corneoscleral rim divided into 2 equal halves
obtain a semicircular sheet of DM. D, The DM rolls with the endothelium on the
outside formed spontaneously after immersion in saline. In this case, the
2 Descemet rolls formed with the axis of the roll perpendicular to the straight
edge of the semicircular graft.
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Hemi–Descemet Membrane Endothelial Keratoplasty
Brief Report Research
Table. Outcomes Following Hemi–Descemet Membrane Endothelial Keratoplasty
Patient No. (Age, y)
and Measure
Postoperative, mo
Preoperative
1
3
6
0.15 (20/125)
0.40 (20/50)
0.50 (20/40)
0.70 (20/29)
2500
1272 (49)
1096 (56)
1069 (57)
Remarks
1 (66)
BCVA (Snellen
equivalent)a
2
ECD, cells/mm
(% decrease)
CCT, μm
682
546
525
Small peripheral
temporal
detachment
523
2 (72)
BCVA (Snellen
equivalent)a
0.15 (20/125)
0.25 (20/80)
0.50 (20/40)
0.50 (20/40)
ECD, cells/mm2
(% decrease)
2500
1730 (31)
1526 (39)
1559 (38)
CCT, μm
707
585
537
Amblyopic eye
534
3 (65)
BCVA (Snellen
equivalent)a
0.70 (20/29)
0.70 (20/29)
0.90 (20/22)
1.20 (20/17)
ECD, cells/mm2
(% decrease)
2900
1768 (39)
1184 (59)
1073 (63)
CCT, μm
Not remarkable
Abbreviations: BCVA, best-corrected
visual acuity; CCT, central corneal
thickness; ECD, endothelial cell
density of hemi–Descemet
membrane endothelial
keratoplasty graft.
a
681
730
488
post mortem. After 1 week in organ culture (CorneaMax,
Eurobio) and endothelial cell evaluation, the corneoscleral
buttons were mounted endothelial side up on a custommade holder with a suction cup. Uveal remnants were
removed, and the DM was loosened with a hockey stick
knife (DORC International) from the scleral spur in a central
direction so that the peripheral DM including the trabecular
meshwork was detached (Figure 1A).
The corneoscleral buttons were then divided into 2
equal halves with a surgical knife (No. 10 knife; SwannMorton) (Figure 1B). The DM was then completely stripped
from the posterior stroma so that 2 semicircular sheets of
DM (2 half-moon–shaped grafts) with an endothelial monolayer were obtained (Figure 1C). In all cases, a DM roll with
the endothelium on the outside formed spontaneously after
immersion of the DM in saline, with the axis of the roll at
any angle to the straight edge of the semicircular graft
(Figure 1D).
Immediately after preparation, endothelial cell appearance, density, and viability were evaluated. The hemiDMEK rolls were then stored in organ culture medium until
the time of transplantation.
Surgery
Surgical procedures were performed using previously
described techniques with a few adjustments.2,9 After insertion into the anterior chamber, the hemi-DMEK graft was
oriented endothelial side down by careful, indirect manipulation with air and fluid. While the anterior chamber was
maintained with fluid and air, the graft was gently spread
over the iris and oriented with the widest graft diameter
across the longest horizontal meridian. An air bubble was
then injected underneath the donor DM to position the tissue onto the recipient’s posterior stroma. 2 The anterior
chamber was completely filled with air for 60 to 90 minutes,
followed by partial air-fluid exchange to leave the eye pres-
489
The BCVA was determined as a
decimal measure.
surized with a minimum of 50% air fill. Postoperative management was identical to that used after standard DMEK
surgery.1,2
Results
The surgery was uneventful in all cases. The hemi-DMEK
graft formed a single roll either with the long axis in line
with the straight edge of the semicircular graft or with the
long axis at an oblique angle to the straight edge, so that an
asymmetric double roll was obtained.2 However, standard
graft unfolding techniques 10 proved to be effective in
unfolding the hemi-DMEK roll. Centering the hemi-DMEK
graft required some additional maneuvers and adjustments.
The graft was positioned with its longer dimension running
along the longer horizontal meridian of the eye. In addition,
the hemi-DMEK roll was positioned eccentrically before
unfolding to ensure that the semicircular hemi-DMEK graft
was well centered after unfolding.
After surgery, the hemi-DMEK grafts were fully attached
in all cases except for a small, persistent peripheral detachment in case 1 that developed by week 1 (Table). No rebubbling procedures were required, and the postoperative
course for all 3 cases was uneventful.
All eyes demonstrated improved corneal clarity and an
improvement in best-corrected visual acuity at 6 months
(Table), and no visual symptoms or disturbances were
reported. Endothelial cell density (ECD) decrease at 6
months was 57%, 38%, and 63% compared with the preoperative eye-bank values (Table).
Owing to the difference in shape between the semicircular DMEK graft and the circular descemetorhexis, areas of
bare corneal stroma were present in all cases. These initially
edematous denuded areas showed deturgescence starting
from the area adjacent to the graft (Figure 2) to clear by
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Research Brief Report
Hemi–Descemet Membrane Endothelial Keratoplasty
Figure 2. Slitlamp and Serial Pachymetry Images of All Cases at 1, 3, and 6 Months After Hemi–Descemet Membrane Endothelial Keratoplasty
(Hemi-DMEK)
Month 1
Month 3
Month 6
Case 1
Case 2
Case 3
Corneal thickness (expressed in micrometers according to Pentacam software;
Oculus) is indicated according to the color-coded information. The full yellow
lines outline the approximate position of the hemi-DMEK graft, and the location
of the peripheral graft detachment in case 1 is highlighted by a dotted yellow
line. Note that corneal deturgescence starts in the graft’s center and progresses
outward from 1 month to 6 months. N indicates nasal; OD, right eye; and
T, temporal.
6 months. In case 3, the previously bare cornea stromal
area had a mean (SD) ECD of 770 (10) cells/mm2 and the area
of attached hemi-DMEK had a mean ECD of 1073 (10)
cells/mm2 at 6 months.
Our series may have been too small to evaluate the
potential effects of the hemi-DMEK graft on visual outcome,
since one of the 3 eyes was amblyopic. However, another
eye, which had normal visual potential, reached a bestcorrected visual acuity of 1.20 (Snellen equivalent, 20/17) at
6 months, which may indicate that visual recovery with
hemi-DMEK (half-moon–shaped graft) may be similar to
that with standard DMEK (full-moon–shaped graft). A
return to normal pachymetry values across the cornea in all
cases may be indicative of the eye being able to reach its full
visual potential after hemi-DMEK.
Endothelial cell density decreased in the first month
after hemi-DMEK by 31% to 49%, followed by a decrease
between the second and sixth months of 7% to 24%. The
mean ECD decrease following standard DMEK is approximately 30% to 35% at 6 months postoperatively.1,3 Most of
this decrease has been shown to have occurred by 1 month;
further decreases were relatively small, at approximately
7% per year. 1 3 , 1 4 We postulate that these differences
Discussion
From a technical point of view, hemi-DMEK grafts could be produced using only a slight modification of our standardized harvesting technique.11,12 Tissue stripping was no more complex, and
no tissue loss was encountered due to preparation failure. During surgery, all hemi-DMEK grafts could be unrolled and positioned using our standardized unfolding techniques.10 The only
modification required was to position the hemi-DMEK roll so that
the long, straight edge of the unfolded graft would run along the
longest horizontal meridian of the eye and the hemi-DMEK roll
was slightly eccentric before unfolding. This was done to ensure
that the unfolded hemi-DMEK graft would be centered.
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Hemi–Descemet Membrane Endothelial Keratoplasty
Brief Report Research
m ay b e e x p l a i n e d b y v a r i a t i o n s i n c e l l m i g r a t i o n
between hemi-DMEK and standard DMEK. A different
migrator y pattern may be expec ted in hemi-DMEK
because a semicircular transplant was positioned onto
a circular denuded stroma bed (after a circular descemetorhexis), leaving a larger gap of bare corneal stroma
that has to be repopulated with donor or host endothelial
cells.
Conclusions
We have demonstrated that hemi-DMEK is technically feasible and can be performed with possible good clinical outcomes. However, the limited number of cases in the present
report does not permit one to determine with confidence the
precise frequency of good outcomes.
ARTICLE INFORMATION
REFERENCES
Submitted for Publication: April 2, 2014; final
revision received June 26, 2014; accepted July 4,
2014.
1. Dirisamer M, Ham L, Dapena I, et al. Efficacy of
Descemet membrane endothelial keratoplasty:
clinical outcome of 200 consecutive cases after a
learning curve of 25 cases. Arch Ophthalmol. 2011;
129(11):1435-1443.
Published Online: September 11, 2014.
doi:10.1001/jamaophthalmol.2014.3328.
Author Contributions: Dr Melles had full access to
all the data in the study and takes responsibility for
the integrity of the data and the accuracy of the
data analysis.
Study concept and design: Dirisamer, Dapena,
Melles.
Acquisition, analysis, or interpretation of data: All
authors.
Drafting of the manuscript: Lam, Lie, Melles.
Critical revision of the manuscript for important
intellectual content: Lam, Baydoun, Dirisamer,
Dapena, Melles.
Statistical analysis: Lam.
Administrative, technical, or material support: Lam,
Baydoun, Dirisamer, Lie.
Study supervision: Dirisamer, Dapena, Melles.
Conflict of Interest Disclosures: All authors have
completed and submitted the ICMJE Form for
Disclosure of Potential Conflicts of Interest. Dr Lam
received the Pfizer Ophthalmic Fellowship through
the Royal College of Ophthalmologists in London to
support him in his corneal fellowship at the
Netherlands Institute for Innovative Ocular Surgery.
This fellowship grant is unrelated to this study. Drs
Baydoun and Dapena received a World
Ophthalmology Congress 2014 travel grant
unrelated to this study. Dr Melles is a consultant for
DORC International/Dutch Ophthalmic USA. No
other disclosures are reported.
2. Dapena I, Moutsouris K, Droutsas K, Ham L, van
Dijk K, Melles GR. Standardized “no-touch”
technique for Descemet membrane endothelial
keratoplasty. Arch Ophthalmol. 2011;129(1):88-94.
3. Price MO, Giebel AW, Fairchild KM, Price FW Jr.
Descemet’s membrane endothelial keratoplasty:
prospective multicenter study of visual and
refractive outcomes and endothelial survival.
Ophthalmology. 2009;116(12):2361-2368.
4. Gaum L, Reynolds I, Jones MN, Clarkson AJ,
Gillan HL, Kaye SB. Tissue and corneal donation and
transplantation in the UK. Br J Anaesth. 2012;10(suppl
1):i43-i47.
5. Vajpayee RB, Sharma N, Jhanji V, Titiyal JS,
Tandon R. One donor cornea for 3 recipients: a new
concept for corneal transplantation surgery. Arch
Ophthalmol. 2007;125(4):552-554.
6. Lie JT, Groeneveld-van Beek EA, Ham L, van der
Wees J, Melles GR. More efficient use of donor
corneal tissue with Descemet membrane
endothelial keratoplasty (DMEK): two lamellar
keratoplasty procedures with one donor cornea. Br
J Ophthalmol. 2010;94(9):1265-1266.
7. Heindl LM, Riss S, Bachmann BO, Laaser K, Kruse
FE, Cursiefen C. Split cornea transplantation for 2
recipients: a new strategy to reduce corneal tissue
cost and shortage. Ophthalmology. 2011;118(2):
294-301.
jamaophthalmology.com
8. Heindl LM, Riss S, Laaser K, Bachmann BO, Kruse
FE, Cursiefen C. Split cornea transplantation for 2
recipients—review of the first 100 consecutive
patients. Am J Ophthalmol. 2011;152(4):523-532, e2.
9. Melles GR, Wijdh RH, Nieuwendaal CP.
A technique to excise the Descemet membrane
from a recipient cornea (Descemetorhexis). Cornea.
2004;23(3):286-288.
10. Liarakos VS, Dapena I, Ham L, van Dijk K, Melles
GR. Intraocular graft unfolding techniques in
Descemet membrane endothelial keratoplasty.
JAMA Ophthalmol. 2013;131(1):29-35.
11. Lie JT, Birbal R, Ham L, van der Wees J, Melles
GR. Donor tissue preparation for Descemet
membrane endothelial keratoplasty. J Cataract
Refract Surg. 2008;34(9):1578-1583.
12. Groeneveld EA, Lie JT, van der Wees J,
Bruinsma M, Melles GR. Standardized “no-touch”
donor tissue preparation for DALK and DMEK:
harvesting undamaged anterior and posterior
transplants from the same donor cornea. Acta
Ophthalmol (Copenh). 2013;91(2):145-150.
13. Baydoun L, Tong CM, Tse WW, et al. Endothelial
cell density after Descemet membrane endothelial
keratoplasty: 1 to 5-year follow-up. Am J Ophthalmol.
2012;154(4):762-763.
14. Quilendrino R, Höhn H, Tse WH, et al. Do we
overestimate the endothelial cell “loss” after
Descemet membrane endothelial keratoplasty?
Curr Eye Res. 2013;38(2):260-265.
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