Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in Pseudophakia

1. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in Pseudophakia Reecha Sachdeva, MD1 Ricardo N Sepulveda, MD1 Mark R Barakat, MD1 Lynn Schoenfield, MD2 Jonathan E Sears, MD1 William J Dupps, Jr, MD, PhD1,3,4 1Cole Eye Institute, 2Department of Anatomic Pathology, 3Biomedical Engineering, 4Transplant Cole Eye Institute 9500 Euclid Avenue Cleveland, OH 44195 Abstract Poster Presentation The American Society of Cataract and Refractive Surgery April 4, 2009 Dr. Dupps recieved a travel reimbursement from Reichert. The remaining authors have no financial interest in the subject matter of this poster.

2. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaPurpose To describe the management of a posteriorly dislocated DSAEK graft and discuss possible risk factors which may lead to this rare intraoperative complication

3. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaMethods: Patient Presentation A 72 year old female with glaucoma and diabetes presented for corneal evaluation: Past Ocular History: 9 years prior to presentation: complicated cataract surgery with resultant decentered anterior chamber intraocular lens with superior haptic encapsulated by iris scarring, dense phimosis of the capsular remnants, and fixed pupillary aperture with a large superotemporal iris defect. Intraocular pressure at that point was controlled on maximal medical therapy. Visual acuity was limited to count fingers at two feet. 7 years prior to presentation: A lens exchange was performed, employing a trans-scleraly sutured intraocular lens, along with pars planavitrectomy and implantation of a posteriorly positioned Ahmed glaucoma tube shunt. Post-operative examination initially revealed a well-positioned intraocular lens and glaucoma implant with a superior pupillary defect, well-controlled intraocular pressure off all glaucoma medication, and a best corrected vision stabilized at 20/25.

4. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaMethods: Patient Presentation Upon presentation to Cole Eye Institute for Corneal evaluation: Patient with BSCVA 20/80 in the involved right eye. Examination revealed pseudophakicbullouskeratopathy. Subsequently, a Descemet’s stripping endothelial keratoplasty (DSAEK) was performed.

5. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaMethods: Complication DSAEK in the right eye: The intraoperative course was complicated by spontaneous inversion and unfolding of the donor graft with endothelium facing upward. Immediately after the graft’s orientation was corrected and prior to placement of the air bubble, the fully unfolded graft migrated rapidly through the iris defect toward the tube and into the vitreous cavity. The incision was closed in preparation for pars plana retrieval of the lenticule and repeat DSAEK with new donor tissue.

6. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaMethods: Complication The patient was re-examined the following day, revealing significant corneal edema and the donor lenticule lying on the inferior, extramacular retina. Figures 1 and 2: Donor lenticule found outside the inferotemporal arcade. Retinal pigment epithelium changes within the macula due to previous photocoagulation for diabetic macular edema. Figure 1 Figure 2

7. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaResults: Management The donor lenticule was retrieved two weeks later by a pars planavitrectomy and withdrawn by extending a sclerotomy. The lenticule was found unfolded, endothelial side up, adherent to the retina in a extramacular location. Figure 3: Elevation of the adherent corneal tissue with a Michels pick. Figure 3

8. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaResults: Management Figure 4: Retrieved corneal tissue with intact Descemet’s membrane and stromal edema. No evidence of inflammation or scar formation. Figure 4

9. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaResults: Management DSAEK was repeated through the pre-existing corneal wound with modifications to prevent repeat dislocation: A Keith needle on a 10-0 prolene suture was passed from the nasal limbus across the anterior chamber and through the temporal wound. The needle was then passed through the edge of the donor tissue, the graft folded in a 60/40 configuration, and the needle was passed back into the wound and across the anterior chamber out a second exit point. The suture ends were then clamped, and slack was taken up by the assistant as the graft was inserted. After pressurization of the anterior chamber with continuous air infusion between 30 and 60 mm Hg for several minutes as previously described,1 the prolene suture was removed. 1 Meisler DM, Dupps WJ, Covert DJ, Koenig SB. Use of an air-fluid exchange system to promote graft adhesion during Descemet’s stripping with automated endothelial keratoplasty (DSAEK). J Cataract Refract Surg 2007;33(5):770-2.

10. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaResults: Outcome On the first postoperative day, the graft was fully attached. Six months later, the graft remains attached with a best-corrected vision of 20/60. Figure 5: External photograph revealing attached, clear graft and corneal wound. (postoperative day #1) Figure 5

11. Discussion To our knowledge, this is the first case of posteriorly dislocated endothelial graft in a pseudophakic eye. This rare complication may have been related to several risk factors: - large pupil - iris defect - absence of zonules and capsular support - absence of the anterior hyaloid due to previous vitrectomy The pars plana tube was located in the region of the iris defect and seemed to provide an intraocular current that led to initial inversion of the graft and ultimate posterior dislocation. Also, the orientation of the IOL haptics and fixation sutures relative to the iris defect and the pars plana tube may have been contributory. The haptics were oriented along a superonasal-inferotemporal meridian formed by the axis of fixation—perpendicular to the meridian of the glaucoma implant and to a hemi-meridian with a large iris defect. This configuration provided no haptic barrier to graft migration in the region of the iris defect and would have allowed the IOL to tilt on its fixation axis, yielding to the migrating graft in a trap door fashion and enhancing access to the vitreous cavity.

12. Posterior Dislocation of an Endothelial Keratoplasty Donor Lenticule in PseudophakiaDiscussion Subsequent management of the dislocated graft highlighted several points of interest. - Suturing the lenticule during this procedure in the manner described adds safety in eyes with several pre-existing conditions (please refer to previous slide for risk factors). - The tight adherence of the lenticule to the retina was likely due to the tissue being fully unfolded with the endothelium side up, creating a vacuum between the donor tissue and the retina perhaps by way of its physiologic pump mechanism. This finding suggests that early retrieval is necessary because there is a chance that it could adhere to the fovea. Additionally, while there was no evidence on histopathology of scar formation (Figure 4), it stands to reason that leaving foreign tissue closely apposed to the retina over time would lead to inflammation with subsequent fibrosis and a more difficult surgical repair. - The posterior view through a cornea two weeks after removal of its endothelium was surprisingly clear after intensive administration of topical steroids.