Purpose

1. Two-year Results of Clinicopathologic Evaluation of the Endothelial Keratoplasty Specimens in an Ophthalmic Pathology Laboratory. Ladan Espandar, M.D. 1, Majid Moshirfar, M.D. F.A.C.S. 2 Mark Mifflin, M.D. 2, Nick Mamalis, M.D.2 1. Department of Ophthalmology, Tulane University, New Orleans, LA 2. Department of Ophthalmology, University of Utah, Salt Lake City, UT The authors have no financial or proprietary interest in any of the products or methods mentioned.

2. Purpose • To report clinical and pathologic analyses of different types of endothelial keratoplasty (EK) specimens sent to an ophthalmic pathology laboratory.

3. Background • Endothelial Keratoplasty (EK), a rapidly advancing surgical technique, involves selective replacement of the posterior cornea for the treatment of corneal endothelial dysfunction (Fuchs’ and bullous keratopathy) and compares favorably to standard full-thickness penetrating keratoplasty (PKP) surgery due to better corneal topographic and refractive results.1-4 • We presented a retrospective review of histopathology and clinical findings of specimens from different kinds of EK surgeries with or without revision.

4. Material and Methods • Retrospective review of 63 specimens from 56 eyes, underwent EK with or without revision, was performed at pathology Lab of the John A. Moran Eye Center between January 2005 and July 2007. • Histopathologic evaluation was accomplished with light microscope using hematoxylin and eosin (H&E) and Periodic acid-Schiff (PAS). The interface between the donor tissue and host tissue was assessed for quality of apposition, cellular proliferation, depositions, and opacification. • Clinical data such as Best Corrected Visual Acuity (BCVA) before the original EK or revisions and at last follow-up and time to the original EK, revisions and last follow-up was compiled

5. Results • A total of 63 specimens were reviewed (3 DLEK without revision, 9 DLEK with revision, 37 DSEK/DSAEK without revision, 14 DSEK/DSAEK with revision). • The preoperative diagnosis was Fuchs’ endothelial dystrophy in 46 eyes (82%), bullous keratopathy in 9 eyes (16%) and Chandler's syndrome in one eye (1%). • Surgeries were performed at three centers by five different ophthalmologists.

6. DLEK without revision • Three specimens from three eyes with Fuchs’ dystrophy and mean age of 59.6 years were reviewed. Mean LogMAR BCVA was 0.66±0.3 (20/100) preoperatively and 0.15±0.1 (20/30) on last follow-up (mean: 14 months, range: 12-16 months). • On microscopic examination, there was a posterior lenticule, 1/2-1/3 thickness of posterior stroma, with diffusely thickened Descemet’s membrane, multiple excrescences (guttae) and marked endothelial attenuation. The stromal side of specimens was irregular. (Figure 1)

7. Figure 1

8. DLEK with revision • Nine specimens from 6 eyes (5 with Fuchs’ dystrophy and one with Chandler’s syndrome) with mean age of 67.8 years were included. Mean LogMAR BCVA was 0.65±0.5 (20/200) preoperatively, 0.1±0.4 (20/300) prior to revision, and 0.76±0.5 (20/220) on last follow-up (mean: 18.8 months, range: 5-36 months). The mean time to first revision was 11.5 months (range: 5-30 months). • The reason for revision was primary graft failure in four eyes, thinning and folding of graft with reduced vision in Chandler’s case, and corneal scar in one eye. • Pathologic examination showed no discernable donor-recipient interface with no gapping, opacification, or proliferation at the site of the interface in corneal button specimens. (Figure 2)

9. Figure 2

10. DSEK/DSAEK without revision • Thirty-seven specimens from 37 eyes (30 with Fuchs’ dystrophy and 7 with bullous keratopathy) with mean age of 75.9 years were studied. Mean LogMAR BCVA was 0.76±0.4 (20/180) preoperatively and 0.38±0.2 (20/50) on last follow-up (mean: 4.3 months, range: 10 weeks-12 months). • The specimens demonstrated Descemet’s membrane that was diffusely thickened with multiple excrescences (guttae) in Fuchs’ and markedly attenuation of endothelial layer in bullous keratopathy and Fuchs’. (Figure 3)

11. Figure 3

12. DSEK/DSAEK with revision • Fourteen specimens from 10 eyes (8 with Fuchs’ dystrophy and 2 with bullous keratopathy) with mean age of 66.5 years were evaluated. Mean LogMAR BCVA was 1.46±0.5 (20/200) preoperatively, 1.45 ±0.2 (20/650) prior to revision, and 0.30±0.1 (20/50+) on last follow-up (mean: 7.8 months, range: 1-17 months). The mean time to first revision was 2.9 months (range: same day to 9.5 months). • Four revisions were PKP and six of them were repeated DSEK/DSAEK. The reason for revision was dislocation in 7 eyes with more than 3 times repositioning, and graft wrinkling, scar, and folding in 3 eyes. • Microscopic study showed smooth donor-recipient interface in all specimens (Figure 4)

13. Figure 4

14. Conclusion • Fuchs’ dystrophy is the most common reason for EK. Dislocation rate of DSEK/DSAEK is more common than DLEK, associated with shorter time to failure, and a tendency to have a smoother interface when compared to DLEK. • PKP revisions showed good apposition of the donor graft to the posterior stroma of the host in both DLEK and DSEK/DSAEK. A hypocellular stromal scar was also observed with no gapping, opacification, or proliferation at the site of the interface.

15. References • 1. Terry MA, Ousley PJ. Deep lamellar endothelial keratoplasty in the first United States patients. Early clinical results. Cornea 2001;20:239–43. •  2. Terry MA, Ousley PJ. Rapid visual rehabilitation after endothelial transplants with deep lamellar endothelial keratoplasty (DLEK). Cornea 2004;23:143–53. •  3. Ousley PJ, Terry MA. Stability of vision, topography, and endothelial cell density from 1 Year to 2 Years after deep lamellar endothelial keratoplasty surgery. Ophthalmology 2005;112:50–7. •  4. Terry MA, Ousley PJ. Replacing the endothelium without surface corneal incisions or sutures: first U.S. clinical series with the deep lamellar endothelial keratoplasty procedure. Ophthalmology 2003;110:755–64.