초록
Purpose:
To evaluate the clinical efficacy and shortcomings of neodymium-doped yttrium aluminum garnet (Nd-YAG) laser membranotomy in inadvertently retained host membrane.
Methods:
Among 742 patients who underwent penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK) surgery at Seoul St. Mary’s Hospital between January 2007 and May 2013 by a single surgeon, 10 patients had a thin, opaque membrane in the anterior chamber observed under slit lamp examination and both a subjective decrease in visual acuity and decrease i best corrected visual acuity. A single surgeon performed membranotomy using the Nd-YAG laser at 4.9 months after graft surgery. In this study we compared the differences in visual acuity, endothelial cell count and correlations between distance from donor endothelium and retained host membrane and endothelial loss before and after the graft surgery.
Results:
Patients who had Nd-YAG laser membranotomy performed on the retained host membrane showed significant improvements in visual acuity ( p = 0.039). Donor endothelial cell count was significantly reduced 1 month after Nd-YAG laser. The average distance between donor endothelium and retained host membrane was 712.0 ± 217.5 µm. The distance and the decreased donor endothelial cell count were not statistically correlated (R2 = 0.39, p = 0.072). There were no significant complications after the laser membranotomy.
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References
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![]() | Figure 1.Retained host membrane after keratoplasty (slit lamp photo). (A) Retained host membrane in front of the pupil is seen in slit lamp photo taken at the day after surgery. The opacity of the membrane is marked, even by naked eyes. Clear space is seen between the membrane and recipient’s peripheral cornea. (B) Retained host membrane is perforated in rec-tangular shape, 5 months after the surgery. Visual axis is well spared with 2.0 mm wide, 2.5 mm long perforation area. The cornea is transparent. |
![]() | Figure 2.Cross sectional image at the level of grafted cornea and retained host membrane. (A, B) Distance between graft endothelium and retained host membrane is measured with spectralis-domain HRA anterior OCT imaging taken at the day after surgery. Distance is variable but relatively close to the graft cornea endothelium. Retained host membrane itself is very thin. (C) Spectralis OCT taken 5 months after the surgery. Retained host membrane is perforated, graft corneal endothelium is intact. The membrane is noticeably thicker. HRA = Heidelberg retina angiograph; OCT = optical coherence tomography. |
Table 1.
Baseline ocular characteristics of the study group by primary cause and surgical procedure
Patient | Sex | Age (years) | Primary cause of corneal decompensation | Surgical procedure | Suspected nature of the retention membrane | Membrane detection time (days)* | Laser apply time (months)† |
---|---|---|---|---|---|---|---|
1 | F | 68 | Traumatic scar | DALK | Double anterior chamber | 1 | 4 |
2 | M | 67 | BK after surgery | PKP | Detached host DM | 1 | 7 |
3 | M | 48 | Chemical burn | PKP | Detached host DM | 1 | 4 |
4 | M | 38 | BK after surgery | PKP | Detached host DM | 1 | 5 |
5 | M | 64 | Lipid degeneration | DALK | Double anterior chamber | 1 | 7 |
6 | F | 67 | Granular dystrophy | DALK | Double anterior chamber | 1 | 4 |
7 | F | 73 | ICE syndrome | PKP | Detached host DM | 1 | 5 |
8 | F | 53 | Traumatic scar | DALK | Double anterior chamber | 1 | 4 |
9 | M | 69 | ICE syndrome | PKP | Detached host DM | 1 | 4 |
10 | F | 22 | Acanthoamoeba keratitis | DALK | Double anterior chamber | 1 | 5 |
Average | 56.9 ± 16.5 | 1 | 4.9 ± 1.2 |
Table 2.
Pre- and post operative visual acuity (log MAR)
Patient | BCVA 1 week before PKP (log MAR) | BCVA 1 month after PKP (log MAR)*,† | BCVA 1 month after laser apply (log MAR)* | BCVA 6 months after laser apply (log MAR)* | BCVA 12 months after laser apply (log MAR)* |
---|---|---|---|---|---|
1 | 1.4 | 1.1 | 0.8 | 0.7 | 1.0 |
2 | 1.6 | 2.4 | 2.4 | 2.4 | 2.4 |
3 | 1.8 | 1.2 | 0.3 | 0.4 | 1.4 |
4 | 0.9 | 0.6 | 0.9 | 0.9 | 0.8 |
5 | 1.7 | 1.5 | 0.4 | 0.5 | 0.5 |
6 | 2.4 | 1.9 | 0.6 | 0.5 | 0.4 |
7 | 2 | 1.7 | 1.4 | 1.4 | 1.6 |
8 | 2 | 1.8 | 1.7 | 1.8 | 2.0 |
9 | 1.8 | 0.6 | 0.3 | 0.3 | 0.3 |
10 | 1.8 | 2.4 | 2.4 | 2.4 | 2.4 |
Average | 1.74 ± 0.21 | 1.52 ± 0.18 | 1.12 ± 0.13 | 1.18 ± 0.78 | 1.28 ± 0.8 |
Table 3.
Pre- and postOperative endothelial cell counts by specular microscopy
Patient | CD before PKP*,† | CD 1 month after PKP*,†,‡ | CD 1 month after laser*,† | CD 6 months after laser*,† | CD 12 months after laser*,† |
---|---|---|---|---|---|
1 | Error c | 2,759 | 1,709 | 584 | 729 |
2 | Error c | 1,461 | Error c | Error c | Error c |
3 | 453 | 2,702 | 1,908 | 1,109 | 1,342 |
4 | Error c | 1,883 | 1,033 | 984 | 702 |
5 | Error c | 2,049 | 1,024 | 786 | 724 |
6 | Error c | 2,369 | 1,248 | 675 | 724 |
7 | Error c | 1,915 | 1,048 | 849 | 801 |
8 | Error c | 1,742 | 629 | Error c | Error c |
9 | Error c | 1,097 | 880 | 866 | 840 |
10 | Error c | 903 | 548 | 426 | Error c |
Average | 453 | 1,888 ± 621.7 | 1,114.1 ± 451.6 | 784.9 ± 219.3 | 837.4 ± 227.9 |
Table 4.
Pre- and post operative corneal thickness by ultrasound pachymetry
Patient | CT before PKP (μ m) | CT 1 month after PKP (μ m)* | CT 1 month after laser (μ m) | CT 6 months after laser (μ m) | CT 12 months after laser (μ m) |
---|---|---|---|---|---|
1 | 404 | 499 | 504 | 561 | 543 |
2 | 874 | 605 | 689 | 764 | 787 |
3 | 584 | 593 | 587 | 543 | 583 |
4 | 889 | 652 | 651 | 800 | 868 |
5 | 411 | 569 | 629 | 661 | 682 |
6 | 558 | 669 | 624 | 667 | 674 |
7 | 525 | 564 | 597 | 699 | 678 |
8 | 768 | 771 | 784 | 841 | 883 |
9 | 590 | 564 | 564 | 689 | 712 |
10 | 342 | 893 | 542 | 538 | 572 |
Average | 594.5 ± 192.9 | 637.9 ± 116.4 | 617.1 ± 79.5 | 676.3 ± 106.1 | 698.2 ± 118.1 |
Table 5.
Distance between donor endothelium and donor endothelial cell count differential after laser and Nd-YAG laser delivered energy and numbers of pulses
Patient | Pulse energy (mJ) | Number of pulses | Distance between donor endothelium and retained host membrane (μ m)* | Differential in cell counts 1 month after laser (cells/mm3)† |
---|---|---|---|---|
1 | 1 | 17 | 474 | 1,050 |
2 | 0.8 | 21 | 1,186 | N/A |
3 | 1 | 11 | 696 | 794 |
4 | 1 | 16 | 831 | 850 |
5 | 0.8 | 27 | 591 | 1,025 |
6 | 1 | 17 | 496 | 1,740 |
7 | 0.8 | 14 | 714 | 867 |
8 | 1 | 10 | 675 | 494 |
9 | 0.8 | 13 | 911 | 23 |
10 | 0.8 | 9 | 546 | 903 |
Average | 0.9 ± 0.1 | 15.5 ± 5.5 | 712 ± 217.5 | 821.3 ± 469.0 |