Outcomes and Complications of DSEK in Eyes with Tube shunts or ACIOLs Peter McGannon, M.D. M. Bowes Hamill, M.D. Ruben E. Ramirez, M.D. No Financial Disclosures Cullen Eye Institute, Baylor College of Medicine

Background Previous studies have demonstrated that glaucoma can increase the risk of corneal graft failure1,2. Anterior chamber tube shunts (ACTS) have also been shown to be associated with endothelial failure, rejection and decreased corneal graft survival rate3. Furthermore, the ACTS location poses a unique surgical challenge during lenticule insertion, positioning and air tamponade in Descemet's-stripping endothelial keratoplasty (DSEK). Anterior chamber intraocular lenses (ACIOLs) also present a surgical challenge during DSEK lenticule insertion and positioning. Furthermore, ACIOL position may lead to endothelial trauma. Aldave AJ, Rudd JC, Cohen EJ, et al. The role of glaucoma therapy in the need for repeat penetrating keratoplasty. Cornea. 2000;19:772-776. Reinhard T, Kallmann C, Cepin A, et al. The influence of glaucoma history on graft survival after penetrating keratoplasty. Graefes Arch Clin Exp Ophthalmol. 1997;235:553-557. Rapuano CJ, Schmidt CM, Cohen, et al. Results of alloplastic tube shunt procedures before, during, or after penetrating keratoplasty. Cornea. 1995;14(1):26-32.

Purpose This study evaluates the clinical outcomes and complications of DSEK in eyes with ACTS, ACIOL, or both in the management of corneal endothelial disease.

Methods This was a nonrandomized, comparative, retrospective case series which reviewed the outcomes of DSEK performed by a single surgeon in patients with ACTS or ACIOL. Clinical outcomes including graft dislocation and graft failure rate were assessed as well as best corrected visual acuity (BCVA), intraocular pressure (IOP), and central corneal thickness (CCT) at the 1, 3, 6, and 9 month postoperative examinations (POM1, POM3, POM6, and POM9, respectively). This data was compared to a database of DSEK’s by the same surgeon, during the same time period, with sufficient follow-up and without ACTS or ACIOL.

Surgical Technique DSEK was performed through 3 paracentesis incisions (superior, nasal, and inferior) and a 5mm clear corneal temporal incision. An anterior chamber maintainer with BSS+ was placed through the nasal paracentesis to keep the eye formed during Descemet’s membrane scoring and stripping and lenticule insertion. After the host Descemet’s was removed, Healon® was placed on the endothelial side of the donor lenticule and it was folded in a 50/50 taco fashion. The stromal surface was stained with trypan blue and the lenticule (8.5-9.0 mm, self-cut or hand-cut) was either inserted with forceps or placed on a Sheets glide and inserted into the anterior chamber with a bent 30 gauge needle. Two 10-0 nylon sutures where placed across the temporal wound. The lenticule was unfolded and positioned with a bent 30 gage needle and air. The 100% air bubble was left for 3-15 minutes and at the end of the case eyes were left with a 30%-100% air fill and patients were face up in the recovery room for 1 hour prior to discharge home. Patients were also instructed to remain face up until bedtime.

Results Of the 346 procedures completed from 8/6/2003 to 7/29/2009, 160 had sufficient follow-up at 9 months postoperatively to be included in the study for comparison. Also, of the 346 surgeries performed, 6 were DSEK’s in eyes with ACTS, 8 DSEK’s were done in eyes with an ACIOL, and 2 DSEK’s were performed in eyes with both an ACTS and ACIOL in place. Although the early follow-up for the ACTS and ACIOL group was good (POM1 100%, POM3 94%), the POM6 (ACTS 20%, ACIOL 86%, ACTS + ACIOL 50%) and POM9 (ACTS 40%, ACIOL 43%, ACTS + ACIOL 50%) follow-up in these groups was poor. Final BCVA was limited in 2 patients in the ACIOL group by a previous retinal detachment and a posterior capsular opacity. Final BCVA was limited in 2 patients in the ACTS group by previous retinal trauma and optic atrophy. A patient in the ACTS + ACIOL group developed endophthalmitis but recovered good visual acuity (20/30) after treatment.

Graft Survival & Complications No ACIOL or ACTS ACIOL ACTS ACIOL + ACTS Number of Surgeries 160 8 6 2 Early Dislocations (POD1) 21 (13.1%) 15 Successful refloats 1 (12.5%) Successful Refloat 1 (16.7%) Late Dislocations (>POD1) 2 (1.25%) 1 Successful refloat Successful refloat Failed Grafts (requiring repeat DSEK or PKP) 12 (5.0%) 4 DSEK, 2 PKP from POD1 dislocation; 1 PKP from late dislocation; 5 PKP from primary failure Repeat DSEK from primary failure at 1 month Repeat DSEK from POD1 dislocation Endophthalmitis 1 (0.63%) 1 (50%) Table 1. A comparison of graft complication and failure rates. There were no statistically significant differences between any of the groups.

Results: Best Corrected Visual Acuity * Figure 1. There were no statistically significant differences in BCVA in any group at any post-operative time point between any group. Only the preoperative BCVA in the ACTS group was significantly different (p<0.003) from the no ACTS/ACIOL group.

Results: Intraocular Pressure Figure 2. There were no statistically significant differences in IOP throughout the post-operative period.

Results: Central Corneal Thickness Figure 3. At POM3, there was a significant difference in CCT between the ACIOL group and the no ACTS/ACIOL group (p<0.016). This difference disappeared by POM6. There were no other significant differences at any other follow-up visit up to POM9.

Conclusions Although this is a small sample size with limited follow-up, it is the largest presented series of DSEK in eyes with ACTS and/or ACIOL. Only two other studies have published results of DSEK in eyes with ACTS or ACIOL and both have found the surgical results to be acceptable4,5. Our findings confirm those reports. There was no significant difference in post-operative BCVA or IOP between any of the ACTS and/or ACIOL groups and the no ACTS/ACIOL group. There was a transient increase in CCT for the ACIOL group at POM3 which was gone by the next follow-up visit. Riaz KM, Sugar J, Tu E, et al. Early results of Descemet-stripping and automated endothelial keratoplasty (DSAEK) in patients with glaucoma drainage devices. Cornea. 2009;28(9):959-962. Esquenazi S. Safety of DSAEK in pseudophakic eyes with anterior chamber lenses and Fuchs endothelial dystrophy. Br J Ophthalmol. 2009; 93(4): 558-559.

Conclusions We also found no significant difference in early or late lenticule dislocation or rejection rate. This finding is also consistent with other studies4,5. Limitations of this study include limited follow-up at POM6 and POM9 and small sample size. Also, CCT thickness may not be a good indicator of endothelial function because of variation in implanted graft thickness. Larger studies with consistent long-term follow-up are needed to assess long-term viability of these grafts in compromised anterior segments. Despite these limitations, DSEK in eyes with ACTS and/or ACIOL appears to be an acceptable and beneficial alternative to penetrating keratoplasty. Riaz KM, Sugar J, Tu E, et al. Early results of Descemet-stripping and automated endothelial keratoplasty (DSAEK) in patients with glaucoma drainage devices. Cornea. 2009;28(9):959-962. Esquenazi S. Safety of DSAEK in pseudophakic eyes with anterior chamber lenses and Fuchs endothelial dystrophy. Br J Ophthalmol. 2009; 93(4): 558-559.