Jeffrey J. Ing, MD, FACS, (Delta Eye Medical Group, Loma Linda University School of Medicine, Department of Ophthalmology)Thanh T. Nguyen, OD (Delta Eye Medical Group)

Art W. Giebel, MD (Pacific Cataract and Laser Institute, Loma Linda University School of Medicine, Department of Ophthalmology)

The authors have no financial interest in the subject matter of this poster.

PurposeTo compare one surgeon’s initial experience with Descemet’s stripping endothelial keratoplasty/Descemet’s stripping automated endothelial keratoplasty (DSEK/DSAEK), to his initial experience with Descemet’s membrane endothelial keratoplasty (DMEK)

We retrospectively reviewed charts on one surgeon’s initial 16 eyes that had DSEK/DSAEK (5/05-8/06) with his initial 16 eyes that had DMEK (8/08-1/09). Preoperative and 7-14 month post-operative Snellen acuities (converted to LogMAR) and endothelial cell densities (ECD) were recorded.

Methods

DSEK/DSAEK DSEK tissue was harvested with hand cut lamellar

dissection or precut DSAEK by eye bank using a microkeratome.

DSEK/DSAEK cases: posterior lamellar corneal tissue was inserted using utrata forceps; the tissue was unfolded and an air bubble was placed into the eye to position the tissue.

DSEK/DSAEK graft

DMEK DMEK cases: the Descemet’s endothelial complex (DEC) was

harvested manually while submerged in preservation media (SCUBA technique).

The DEC was injected into the eye (2.75-3.5 mm incision); air bubbles were used to unfold and position the DEC.

DMEK, hours after procedure performed“Minuteman” sign w/microbubble

Results Eyes with other pathology

were excluded from average visual acuity analysis.*

DSEK: The average preoperative acuity was 20/87 (0.64 logMAR). The average 7-14 month postoperative acuity was 20/44 (0.34 logMAR).

DSEK or DSAEK # Pre -Snellen Pre-LogMAR

7-14mo Snellen

7-14 mo LogMAR

1 20/60+ 0.48 20/80- 0.60

2 20/50 0.40 20/40- 0.30

3 20/50 0.40 20/40cc 0.30

4 20/40- 0.30 20/30 0.18

5 20/60- 0.48 20/50+ 0.40

6* 20/100-cc 0.70 20/50- 0.40

7* 20/100 0.70 20/70 0.54

8* 20/HM >1.3 20/400 1.30

9* 20/60-cc 0.48 20/100- 0.70

10* 20/50+ 0.40 20/80+ AR 0.60

11* 20/30- 0.18 20/40- 0.30

12 20/HMsc >1.3 20/30 0.18

13* 20/200 1.00 20/100- 0.70

14 20/70cc 0.54 20/30-cc 0.13

15 20/70- 0.54 Deceased Deceased

16* 20/100cc 0.70 20/50 0.40

Average >20/87 >0.64 20/44 0.34

Manifest refraction acuities were recorded unless otherwise noted:

with habitual correction (cc), without correction (sc), autorefractor (AR).

Results Eyes with other pathology were

excluded from average visual acuity analysis.†

DMEK: The average pre-operative acuity was 20/123 (0.79 logMAR), the average 7-14 month postoperative acuity was 20/24 (0.08 logMAR).

DMEK #Pre-

Snellen Pre-LogMAR7-14mo Snellen

7-14 LogMAR

1 20/200sc 1.00 20/20 0.00

2 20/200cc 1.00 20/30+* 0.13*

3 20/400cc 1.30 20/25 0.10

4 20/100sc 0.70 20/25 0.10

5 20/50+ 0.40 20/25+ 0.10

6 20/400 PH 1.30 20/25 0.10

7 20/60 0.48 20/25+ 0.10

8 † 20/70-cc 0.54 20/40+ 0.30

9 20/50+cc 0.40 20/20 0.00

10 † 20/60+/- 0.48 20/30* 0.13*

11 † 20/50cc 0.40 20/30+ 0.13

12 † 20/60+ 0.48 20/30 0.13

13 20/70 0.54 20/30 0.13

14 † 20/400cc 1.30 20/50+ 0.40

15 † 20/100 0.70 20/40 0.30

16** 20/20- 0.00 Failed n/a

Average 20/123 0.79 20/24 0.08

Manifest refraction acuities were recorded unless otherwise noted:

with habitual correction (cc), without correction (sc), pin-holed (PH)

*4-6 month data input due to no 7-14 month follow-up data available.

**DMEK #16 had localized non resolving corneal edema preoperative, failed and was excluded

from postoperative visual acuity analysis

Results Average endothelial cell density decreased by 47% for

DSEK/DSAEK and by 42% for DMEK at the 7-16 month interval.

DSEK # Donor ECD 7-14mo ECD % Decrease

1 2832 n/a n/a

2 3048 n/a n/a

3 2778 2163 22%

4 3448 2074 40%

5 2949 n/a n/a

6 4060 n/a n/a

7 3129 n/a n/a

8 3260 867 73%

9 2865 1881 34%

10 3040 n/a n/a

11 3174 n/a n/a

12 2798 967 65%

13 2985 n/a n/a

14 3050 n/a n/a

15 3052 Deceased n/a

16 3017 n/a n/a

Average 47%

DMEK # Donor ECD 7-14mo ECD % Decrease

1 3262 1000 69%

2 2964 2502 16%

3 3108 2157 31%

4 2780 1122 60%

5 3003 1331 56%

6 3322 2387 28%

7 2994 805 73%

8 3115 2312 26%

9 3155 1958 38%

10 3258 910* 72%*

11 2748 1579 43%

12 3077 2719 12%

13 3067 1613 47%

14 2865 1222 57%

15 2985 2103 30%

16 3135 Failed n/a

Average 42%

*4-6 month data input due to no 7-14 month follow-up data available.

Results In DSEK one donor tissue was wasted due to damage

during hand cut lamellar dissection. In DMEK one donor tissue was wasted due to unfolding

difficulty.

Descemet’s endothelial complex after injection into the anterior chamber. Endothelium Is on the outside of the DEC roll

Discussion

Caveats of StudyRetrospective DesignCurrent DSAEK techniques have improved over

older DSEK techniques and the learning curve is significantly shortened with precut tissue.

Endothelial cell density (ECD) measurements○ Single measurement (not averaged)○ Manual counting by different technicians○ Difficulty measuring post DSEK/DSAEK ECD

Learning Curve –our opinion It is the opinion of the authors that DMEK is still

evolving as a technique. DMEK has a steep learning curve. Taking a course and practice in the lab with donor tissue improves results. Some of the maneuvers needed for DMEK are different from anything else done in ocular surgery. However, previous experience with endothelial keratoplasty: Descemet’s stripping and bubble management make the learning curve easier. DMEK may be less equipment intensive and the incision size can be smaller.

Conclusion On average DMEK eyes had better post-operative

vision than DSEK/DSAEK eyes. There was insufficient endothelial cell data for the

DSEK/DSAEK eyes to allow a good comparison with DMEK data.

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