Postoperative glaucoma following keratoprosthesis (artificial cornea) implantation is a challenge, as it is often refractory to conventional management.
A retrospective chart review by Minh T Nguyen, found that eyes with a type 1 keratoprosthesis (KPro) appear to have relatively good intermediate-term glaucoma management with the Ahmed glaucoma valve (AGV), though some tube-related complications were seen.
Study Design
This was a retrospective study involving 38 patients (38 eyes) with a type 1 KPro who underwent AGV placement for IOP control between 2009–2021 at a single hospital in India. All eyes received AGV implants either at the time of or following type 1 KPro implantation, with the drainage tubes predominantly placed in the ciliary sulcus.
Outcomes
- The median follow-up duration was 30.5 months (range 6.5–30.5 months).
- Following AGV implantation, median IOP significantly declined from 30.4 mm Hg to 13.5 mm Hg.
- The average number of glaucoma medications decreased from 3.4 to 1.7.
- BCVA remained stable.
- Humphrey visual field analysis showed progression in 10 eyes (26.3%), with an overall decrease in mean deviation from –13.5 to –26 dB.
- Postoperative complications occurred in 8 eyes (21%), including 7 tube-related complications that underwent successful surgical repair; there were no instances of implant extrusion or endophthalmitis.
Limitations
Similar to other retrospective chart reviews, this study lacked a control group for direct comparison. Additionally, many patients had relatively short follow-up, as brief as 6.5 months, which may not have been sufficient to assess late-onset complications such as implant extrusion or endophthalmitis. The limited follow-up duration also makes it difficult to reliably assess long-term glaucoma stability.
Clinical Significance
This study supports the integration of glaucoma drainage device implantation, particularly the AGV, in eyes with a type 1 KPro to prevent the onset or progression of glaucoma, one of the most serious vision-threatening complications associated with KPro. However, tube-related issues can still occur, highlighting the need for careful, long-term monitoring to preserve visual outcomes.
