Glaucoma drainage devices in Boston keratprosthesis type 1 patients:Ahmed glaucoma valve versus baerveldt glaucoma valve
Authors: Joseph R. Hakim1, Dominique Geoffrion2, Mona Harissi-Dagher3.
1Universtié de Montréal, 2McGill University, 3Université de Montréal.
Disclosure Block:
J.R. Hakim: None. D. Geoffrion: None. M. Harissi-Dagher: None.
Abstract Body:
Purpose: To compare the long-term outcomes
of glaucoma drainage devices (GDD) in Boston keratoprosthesis type 1 (KPro)
patients, specifically those of the Ahmed glaucoma valve (AGV) versus those of
the Baerveldt glaucoma implant (BGI).
Study Design: Retrospective cohort study.
Methods: Retrospective cohort study of 44 eyes (44 patients) implanted
with a KPro between 2008 and 2017. KPro eyes with AGV (n=35) were compared to
those with BGI (n=9) in the main cohort. A sub-cohort comparing KPro eyes with
AGV installed pre-KPro (n=9) to those with BGI installed pre-KPro (n=7) was
further examined. The primary outcome was GDD failure, defined by uncontrolled
intraocular pressure, additional glaucoma surgery or tube removal. Secondary
outcomes included GDD related complications, change in best-corrected visual
acuity (BCVA), intraocular pressure (IOP) and number of glaucoma medications.
Differences in outcomes were compared using parametric and non-parametric
tests, as well as Kaplan-Meier survival log-rank test to compare failure over
time.
Results: Mean age was 60.0±15.4 years at KPro surgery and mean follow-up
time was 5.4 ±2.3 years. In the main cohort, KPro eyes with AGV had a higher
cumulative failure probability over time compared to that of eyes with BGI
(57.1% versus 11.1%; P=0.039). More eyes with AGV required additional glaucoma
surgery procedures compared to eyes with BGI (37.1% vs. 11.1%; P=0.135). The
occurrence of GDD-related complications was similar between AGV and BGI (37.1%
vs 33.3%, P=0.832). Regarding BCVA, there was an improvement in 55.6% of eyes
with BGI compared to 42.9% of AGV eyes (P=0.71.) Change in IOP and number of
topical glaucoma medications was also comparable in both groups (P>0.05)
over the follow-up period. In the subcohort, outcomes between GDDs implanted before
KPro surgery were concordant with those of the main cohort.
Conclusions: Compared to AGV, BGI implanted in KPro eyes was associated
with lower GDD failure rates and slightly higher occurrence of improved BCVA
while having a comparable occurrence of long-term complications.
