Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Mar;33(3):469-477.
doi: 10.1038/s41433-018-0243-8. Epub 2018 Oct 24.

A multi-centre interventional case series of 259 ab-interno Xen gel implants for glaucoma, with and without combined cataract surgery

Ayesha Karimi  1 , Dan Lindfield  2 , Andrew Turnbull  3 , Chrysostomos Dimitriou  4 , Bhairavi Bhatia  4 , Mahmoud Radwan  4 , Pieter Gouws  5 , Abdul Hanifudin  3 , Nishani Amerasinghe  3 , Aby Jacob  3
Affiliations

A multi-centre interventional case series of 259 ab-interno Xen gel implants for glaucoma, with and without combined cataract surgery

Ayesha Karimi et al. Eye (Lond). 2019 Mar.

Abstract

Aims: To assess the efficacy of Xen in reducing intraocular pressure (IOP) in varying glaucoma subtypes. To assess the effect of combined phacoemulsification. To determine the frequency of complications and explore further bleb management needed.

Methods: Retrospective case note review of all patients undergoing Xen implantation across four centres from August 2015 to May 2017.

Results: In total, 259 consecutive surgeries of 226 patients were reviewed. IOP reduced from 19.3 (SD ± 6.0) mmHg preoperatively to 14.2 (SD ± 4.4) at month 12 and 13.5 (SD ± 3.3) at month 18 (p < 0.0001). Medication usage reduced from 2.6 (±1.1) preoperatively to 0.8 (±1.0) at month 12 (p < 0.0001) and 1.1 (±1.3) medications at month 18 (p < 0.0001). Simultaneous phacoemulsification did not alter outcomes as Xen IOP was 14.3 (SD ± 4.7) mmHg and Phaco-Xen was 13.8 (SD ± 2.6) mmHg at month 12 (p = 0.5367). Xen appears to be effective in previous failed filtration surgery. Adverse events included: IOP spikes of ≥30 mmHg in 33 (12.7%) cases, secondary filtration surgery required in 24 (9.3%) cases; implant exposure in 6 (2.3%) cases; persistent hypotonous maculopathy in 5 (1.9%) cases; persistent choroidal effusions in 4 (1.5%) cases; a cyclodialysis cleft secondary to implant insertion in 1 (0.5%) case; and 1 (0.5%) case of endophthalmitis post-implant bleb resuturing. In all, 40.9% of cases required postoperative bleb needling or antimetabolite injection.

Conclusions: Xen reduces IOP and medications at 18 months. Adverse events are uncommon. Careful postoperative surveillance and low threshold for bleb management is needed. Xen is safe and effective in mild to moderate glaucoma.

PubMed Disclaimer

Conflict of interest statement

DL reports previously receiving honoraria from Allergan, Alcon, Endo Optiks, Thea, MSD, BVI Visitec and Santen outside of this work. CD reports receiving an educational travel grant from Allergan outside the work. PG reports previously receiving honoraria from Allergan prior to the work. NA reports previously receiving an educational travel grant from Nuffield Health and honoraria from Allergan and Thea outside this work. AJ reports receiving non-financial support from Aquesys prior to the study and a grant as well as non-financial support from Allergan outside the work. The remaining authors declare that they have no conflict of interest.

Figures

Fig. 1
Fig. 1
Mean IOP and mean number of IOP-lowering medications required pre- and post Xen implant at day 1, week 1, month 1, month 3, month 6, month 9, month 12 and month 18, shown with 95% confidence intervals. Comparison of the pre- and postoperative IOP and number of medications at each time point was performed with the paired Student’s t test and Wilcoxon signed rank test respectively (p < 0.05)
Fig. 2
Fig. 2
Kaplan−Meier survival plots for all Xen surgeries that completed 12-month follow-up (n = 91). Complete surgical success was defined as IOP ≤ 21 mmHg and a 20% reduction from preoperative IOP without medications and without significant complications (secondary filtration surgery, endophthalmitis or unresolved hypotonous maculopathy)
Fig. 3
Fig. 3
Mean IOP pre- and post-op at day 1, week 1, month 1, month 3, month 6, month 9, month 12 and month 18, for Xen with and without combined cataract surgery, shown with 95% confidence intervals. Comparison of mean IOP between the two groups at each time point was performed with the Student’s t test (p < 0.05)
See this image and copyright information in PMC

References

    1. Freedman J. What is new after 40 years of glaucoma implants. J Glaucoma. 2010;19:504–8. doi: 10.1097/IJG.0b013e3181ca7850. - DOI - PubMed
    1. Vijaya L, Manish P, Ronnie G, Shantha B. Management of complications in glaucoma surgery. Indian J Ophthalmol. 2011;59:131. doi: 10.4103/0301-4738.73689. - DOI - PMC - PubMed
    1. DeBry P. Incidence of late-onset bleb-related complications following trabeculectomy with mitomycin. Arch Ophthalmol. 2002;120:297. doi: 10.1001/archopht.120.3.297. - DOI - PubMed
    1. Lewis R. Ab interno approach to the subconjunctival space using a collagen glaucoma stent. J Cataract Refract Surg. 2014;40:1301–6. doi: 10.1016/j.jcrs.2014.01.032. - DOI - PubMed
    1. Manasses D, Au L. The new era of glaucoma micro-stent surgery. Ophthalmol Ther. 2016;5:135–46. doi: 10.1007/s40123-016-0054-6. - DOI - PMC - PubMed