Abstract
Purpose: :
To examine the effectiveness of glaucoma implants for the control of intraocular pressure after Type I Boston Keratoprosthesis (K-Pro).
Methods: :
Retrospective case series.
Results: :
Forty-six K-Pro procedures were performed in 43 eyes of 42 patients between December 2006 and November 2009. Of 31 eyes with pre-existing glaucoma or ocular hypertension (intraocular pressure (IOP) > 23), 10 had glaucoma implants prior to K-Pro. Four of 10 were selected to undergo concurrent glaucoma surgery at the time of K-Pro implantation, either revision of a prior implant or placement of a new implant. An additional 4 eyes without history of glaucoma implant received new implants at the time of K-Pro, and 1 eye required an implant after K-Pro. With mean follow-up of 11±8.5 months, only 1 of 15 required an additional IOP-lowering procedure after glaucoma implant and K-Pro. Two of 15 required implant revision after K-Pro for tube exposure (only 1 of the 2 had glaucoma surgery at the time of K-Pro). Of 8 eyes with concurrent glaucoma implant, 4 of 8 were noted to have elevated IOP at some point during post-operative year 1 (POY1, firm by palpation or scleral pneumotonometry reading > 23). However, of those 4, only 1 required an additional IOP-lowering procedure; the rest were treated successfully with additional medications. Of 6 eyes with prior glaucoma implants that did not undergo concurrent glaucoma surgery, 3 had elevated IOP during POY1, but none required additional IOP-lowering procedures. Of the remaining 28 eyes without glaucoma implants (16 with pre-existing glaucoma), 9 had elevated IOP readings during POY1. Two had subsequent transcleral diode cyclophotocoagulation (one with pre-existing glaucoma, one without); the rest were maintained on medication alone.
Conclusions: :
Based on early follow-up in our cohort, most eyes have been able to maintain an IOP of 23 or less on medical therapy alone without the need for additional IOP-lowering procedures after K-Pro. However, for those that cannot, glaucoma implants are a useful adjunct. Long-term follow-up will be necessary to determine if patients show progression of glaucoma.
Keywords: keratoprostheses • intraocular pressure