An 86-year-old man presented to our clinic for evaluation of worsening vision in his right eye. The patient had type 2 diabetes mellitus, paroxysmal atrial fibrillation, hyperlipidemia, and hypertension. He was pseudophakic in both eyes and had a history of primary open-angle glaucoma that was previously treated with maximum medical therapy. He developed bullous keratopathy of the right eye after glaucoma filtering surgery. The patient reported he developed elevated IOPs after an endothelial corneal transplant was performed in the right eye, requiring a second glaucoma surgery, a Xen gel implant (Allergan). These previous ocular surgeries were performed when the patient lived in Florida.
Upon initial examination, the patient’s visual acuity was hand motion in the right eye and 20/50-1 in the left eye. IOPs were 19 mm Hg OD and 15 mm Hg OS. The right eye findings included diffuse corneal edema with extended deep corneal neovascularization from 3 o’clock to 7 o’clock, an atrophic iris with transillumination, and presence of anterior synechiae extending from 2 o’clock to 6 o’clock with a shallow chamber nasally. Examination of the left eye was unremarkable.
The patient was diagnosed with endothelial graft failure and extended anterior synechiae in the right eye. It was decided to perform repeat DSAEK with synechiolysis.
The Surgery
During surgery, it was noted that the failed graft was attached 360° to the iris by fibrotic tissue. In an attempt to remove it, MST retina microforceps and scissors were used to hold the graft and cut the fibrotic membrane adherences to the iris, but this maneuver was unsuccessful. Then, 23-gauge curved retina scissors were used with success to remove the fibrotic membrane adherences attaching the graft to the iris (Figure 1). An Endoserter injector (CorneaGen) was used to deploy tissue into the anterior chamber with caution, owing to significant iris atrophy. The tissue was unfolded and centralized with the help of a Sinskey hook. A 20% SF6 gas bubble was injected under the graft. The full gas bubble could not be maintained despite closing all incisions. Therefore, a 30-gauge needle was used to inject gas into the anterior chamber (Figure 2). A medium-sized gas bubble was held inside the anterior chamber, and IOP was within normal range.
Figure 1. The fibrotic membrane adherences attaching the graft to the iris were removed using 23-gauge curved retina scissors.
Figure 2. A 30-gauge needle was used to inject gas into the anterior chamber.
Outcome
Despite a fully attached DSAEK graft post surgery, the patient’s visual acuity remained hand motion. At the 1-month postoperative visit, corneal edema had improved; however, at the 6-week visit, the patient presented with worsening and persistent corneal edema and 360° anterior synechiae. The repeat DSAEK had failed, and significant anterior synechiae developed despite the graft remaining attached in the correct orientation.
The patient plans to move back to Florida where he will continue his eye care.
Discussion
The most common cause of endothelial graft failure is endothelial cell loss from tissue preparation and surgical stress. In addition, the presence of glaucoma drainage devices and peripheral anterior synechiae (PAS) have been found to increase the likelihood of retrocorneal membrane formation and further PAS formation from the presence of proinflammatory cytokines.1,2 In this case, the presence of a glaucoma filtering surgery before the first endothelial graft placement most likely contributed to the formation of the retrocorneal membrane, which contributed to graft dislocation, adherence to the iris, and subsequent graft failure. We hypothesized that endothelial cell injury from persistent PAS after the re-graft and graft manipulation in surgery contributed to the second DSAEK failure.
Conclusion
In retrospect, an anterior segment image could have provided further information into the extent and severity of the retrocorneal membrane and the PAS causing graft adherence to the iris. A penetrating keratoplasty might have been a better long-term option in such an anterior segment complex case.
1. Shulman J, Kropinak M, Ritterband DC, et al. Failed descemet-stripping automated endothelial keratoplasty grafts: a clinicopathologic analysis. Am J Ophthalmol. 2009;148(5).
2. Naranjo A, Pirakitikulr N, Pelaez D, et al. Clinicopathologic correlations of retrocorneal membranes associated with endothelial corneal graft failure. Am J Ophthalmol. 2021;222:24–33.
