Innovative Approaches to Glaucoma Management of Boston Keratoprosthesis Type 1

Abstract

Glaucoma remains a prevalent disorder and visual limiting factor after Boston keratoprosthesis type 1 implantation. Patients with glaucoma have worse initial and late visual acuity outcomes after otherwise successful keratoprosthesis implantation. Management of glaucoma in the setting of a keratoprosthesis is challenging because of relatively rapid progression and an inability to accurately measure intraocular pressure (IOP). In addition, there are no standard guidelines for glaucoma surveillance and monitoring after keratoprosthesis surgery. This report provides a review of the current literature and offers innovative strategies that will overcome the challenges in managing glaucoma in the setting of a Boston keratoprosthesis type 1 implant. The topics that will be discussed in this section include alternative methods for IOP measurement, rationales and surgical techniques for a pars plana tube placement for glaucoma drainage device, effective medical and laser treatment, the risk for IOP elevations after YAG laser, and practical guides to glaucoma surveillance and monitoring.

Resolution of an exposed pars plana Baerveldt shunt in a patient with a Boston keratoprosthesis type 1 without surgery

“…Tube erosion can also be minimized with placement in the vitreous cavity versus the anterior chamber, and the tube can be reinforced with a patch graft made of fascia lata, pericardium, sclera, cornea, or dura mater. 4,14,15 The removal and replacement of the contact lens will vary. In general, the contact lens should be worn continuously and removed for cleaning and disinfection in office at each follow-up visit.…”

Comparison of Visual and Anatomical Outcomes of Eyes Undergoing Type I Boston Keratoprosthesis With Combination Pars Plana Vitrectomy With Eyes Without Combination Vitrectomy

“…Firstly, there is limited space for a glaucoma tube in the anterior chamber after keratoprosthesis implantation; the average functional anterior chamber depth is 0.21 mm. 18, 19 Secondly, angle closure in eyes with keratoprosthesis is prevalent, extensive and progressive. 19 Anterior segment OCT has demonstrated that anterior chamber depth and anterior chamber angle dimension are dynamic in these eyes and previous reports have documented anterior chamber tube occlusion.…”

<p>Boston Type 1 Keratoprosthesis: Updated Perspectives</p>

“…Glaucoma drainage device (GDD) placement and endoscopic or transscleral diode cyclophotocoagulation are highly effective modalities used for IOP control in most publications. 19,[65][66][67] Most studies advocate prior GDD surgery or concurrent BKPro and GDD implantation in eyes with preexisting glaucoma. 67,68 Lentis and colleagues demonstrated that eyes receiving BKPro plus GDD implantation had significantly lower IOP than eyes receiving BKPro alone with no significant difference in the rate of serious vision-threatening complications.…”

“…19,[65][66][67] Most studies advocate prior GDD surgery or concurrent BKPro and GDD implantation in eyes with preexisting glaucoma. 67,68 Lentis and colleagues demonstrated that eyes receiving BKPro plus GDD implantation had significantly lower IOP than eyes receiving BKPro alone with no significant difference in the rate of serious vision-threatening complications. 69 Combined pars plana vitrectomy and GDD implantation is a suitable alternative that has shown good efficacy in IOP control with a decreased risk of complications 70,71 (Figure 3).…”

“…There is a clear need to develop alternative methods for reliable IOP measurement. 67,83 Promising results of telemetric IOP monitoring in 12 patients implanted with an intraocular sensor in the ciliary sulcus at the time of BKPro surgery were recently published by Ender and colleagues showing good safety and tolerability of the device as well as successful telemetric IOP assessment. 84 Similarly, plans to integrate a pressure sensor (micro-optomechanical pressure sensor) in the BKPro device are underway.…”