Rebubbling Rates After Artificial Endothelial Keratoprosthesis Implantation

To describe early results and complications after the implantation of the novel posterior keratoprosthesis Endoart® (EyeYon Medical, Israel, CE approved 08/21) for endothelial replacement in patients with impaired blood-aqueous barrierdue to chronic glaucoma, trauma, or artificial devices such as anterior chamber intraocular lens, iris implant or glaucoma drainage devices. These patients are at very high risk for secondary graft failure soon after endothelial transplantation (DMEK or DSAEK). This novel artificial endothelial prosthesis acts as a barrier for aqueous humor and might allow a permanent stabilization of the corneal edema.

19 patients after implantation of the keratoprosthesis EndoArt® were retrospectively analyzed. The prosthesis was positioned on the posterior stroma and secured by a C3F8 12% gas bubble and 1-4 transcorneal sutures during surgery. We investigated the need for additional gas injections into the anterior chamber (rebubbling) and analyzed whether risk factors for implant detachment could be found.

19 eyes after EndoArt® implantation were included (chronic glaucoma (n=16), glaucoma surgery (n=11), glaucoma drainage devices (GDD, n=5), keratoplasties (n=14)).

7 patients (36.8%) did not need rebubbling, 63.2% (n=12) at least 1 rebubbling, and 7 patients required repetitive ones. Most had additional risk factors such as aniridia (n=2), trauma/ after PK (n=6), or anterior synechia (n=2); 1 had 2 GDDs and was aphakic. Four had an intact iris diaphragm and pseudophakia; of those, only 2 had additional risk factors besides chronic glaucoma.

Of the 7 patients with repetitive need for rebubbling, 57.1% had 3 (n=3) or 4 sutures (n=1), 42.9% had 1 (n=2) or 2 (n=1) sutures, in case of no need for rebubbling 85.7% had 1(n=2) or 2 (n=4) sutures.

The major complication after EndoArt® implantation in our cohort was rebubbling. The cohort is too small to identify a pattern of risk factors, but surgical protective suggestions can be made. The use of lesser sutures seems beneficial, but a history of PK or trauma seems disadvantageous. Long-term results of patients after EndoArt® implantation, especially regarding rebubbling rates, are still pending.