One-year result of XEN45 implant for glaucoma: efficacy, safety, and postoperative management

Abstract

PurposeTo report the efficacy, safety profile, and postoperative management of XEN45 implant at 12-month follow-up.Patients and methodsThis was a retrospective, non-randomised interventional case series involving patients who underwent XEN45 implantation by a single, experienced glaucoma specialist in a tertiary centre. Primary outcome measures were the intraocular pressure (IOP) and the number of medications at 1-year follow-up visit. Two IOP criteria were chosen to measure success: IOP ≤21 mm Hg and ≥20% reduction from baseline (criteria one); and IOP ≤15 mm Hg and ≥30% reduction from baseline (criteria two).ResultsAll 39 eyes completed 1-year follow-up. The mean preoperative IOP was 24.9±7.8 mm Hg on three drops, which reduced to 14.5±3.4 mm Hg at month 12 (P<0.005) on 0.7 drops (P<0.005). On the basis of criteria one, the cumulative probability of success at 1 year was 87.0% without medication and 92.0% with medication. On the basis of criteria two, cumulative probability of success was 62.0% without medication and 64.0% with medication. Bleb intervention with a median of 2 (range 1-4) was required for 51.3% of eyes. Implant was obstructed by iris tissue in three eyes (7.7%); one eye (2.6%) developed hyphaema; eight eyes (20.5%) had numerical hypotony (IOP≤5 mm Hg) at day 1, of which all spontaneously resolved by week 4 apart from one eye.ConclusionsThe XEN45 implant proved to be an effective treatment with a good safety profile at 1-year follow-up period. The high rate of postoperative bleb intervention does not make XEN45 a 'fit-and-forget' procedure and therefore the procedure should ideally be performed by surgeons experienced in bleb management.

Figure 1

(a) Change in mean IOPs over 12-month follow-up visits. (b) Change in number drops at last follow-up visit from baseline.

Figure 2

Scatter plot of preoperative vs postoperative IOP at 1-year follow visit with lines demonstrating the proportion of eyes that met various criteria for success (≤21, ≤18, ≤15, and ≤12 mm Hg). C, complete success; diamond, not on drops; Q, qualified success; square, back on drops.

Figure 3

Kaplan–Meier survival curve at 12 months, defining failure as (a) IOP >21 mm Hg or not reduced by 20% below baseline on two consecutive study visits, or IOP of <6 mm Hg or needing further glaucoma drainage surgery, and (b) IOP >15 mm Hg or not reduced by 30% below baseline on two consecutive study visits, or IOP of <6 mm Hg or needing further glaucoma drainage surgery.

Figure 4

Mean IOP and number of drops in the bleb intervention vs no bleb intervention group over 12-month follow-up visits.