Implantation of XEN After Failed Trabeculectomy: an Efficient Therapy?

Abstract

Background Trabeculectomy (TE) has been the standard procedure in glaucoma surgery for a long time. This study examined the efficacy and safety profile of XEN45 Gel Stent (XEN) after failed and/or scarred trabeculectomy.

Material and Methods We analysed all files of patients, who received a XEN after insufficient TE and examined changes in intraocular pressure (IOP), IOP-lowering medication, best corrected visual acuity, visual field tests as well as the intra- and postoperative complications recorded within a 12-month follow-up period.

Results 31 eyes of 28 patients were analysed in our study (mean age: 66,2 ± 13,4 years; 39% female; 48% right eye; mean follow-up after TE: 70,3 ± 64,9 months). The mean IOP decreased from 23,5 ± 6,5 to 18,0 ± 5,3 mmHg (− 23,5% compared to baseline-IOP; p = 0,01) while the mean IOP-lowering medication could be reduced from 2,8 ± 1,1 to 1,1 ± 1,5 (p < 0,01) 12 months after XEN-implantation. The mean visual acuity did not change significantly (pre-op: 0,5 ± 0,6 logMAR; 12 months post-op: 0,5 ± 0,6 logMAR). The most common complications postoperatively were choroideal detachment due to postoperative hypotony in 4 eyes (13%), a needling procedure in 9 eyes (29%), a Re-XEN-Implantation in 4 eyes (13%), an open revision of the conjunctiva in 3 eyes (10%), and a Re-TE in 1 eye (3%) as well as an Ahmed-Valve implantation in 2 eyes (6%). Overall, neither needling procedure nor further glaucoma surgery was necessary in 19 eyes (61%). In 10 of 22 evaluable eyes (45%) an IOP reduction of > 20% was achieved 12 months after XEN implantation.

Conclusion XEN could be an effective method to reduce IOP after failed TE. The rate of complications seems to be low and the rate of needling procedures and/or revisions is acceptable.

Key words

XEN - MIGS - failed trabeculectomy - refractory glaucoma

Publication History

Received: 15 March 2021

Accepted: 14 July 2021

Article published online:
27 September 2021

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