24-month outcomes of XEN45 gel implant versus trabeculectomy in primary glaucoma

Purpose To compare the efficacy and safety profiles of XEN implant versus trabeculectomy as a surgical intervention for primary glaucoma Methods A retrospective cohort study of mild to moderate stage glaucoma patients, who had undergone either XEN implantation or trabeculectomy with adjunctive mitomycin C, was performed in a tertiary eye center Results Fifty-seven eyes for XEN implant and 57 eyes for trabeculectomy with medically uncontrolled glaucoma were included. Preoperative IOP was 16–33 mmHg. Visual field mean deviation was -9.11±6.93 dB in XEN group, and -9.67±5.06 dB in trabeculectomy group (p = 0.195). At the 24-month timepoint, mean IOP was reduced from 21.6±4.0 to 14.6±3.5 mmHg (32.4% reduction) in the XEN group (p<0.001), and from 22.5±5.8 to 12.5±4.1 mmHg (44.4% reduction) in the trabeculectomy group (p<0.001). Final IOP in XEN was significantly higher than trabeculectomy (p = 0.008) with lesser mean IOP percentage reduction at month 24 (p = 0.045). Mean number of medications was reduced from 2.2±1.4 to 0.5±0.7 in XEN group (p<0.001), and from 2.4±0.7 to 0.8±1.3 in trabeculectomy group (p<0.001). Final number of medications was not different between the groups (p = 0.225). Surgical success was comparable between XEN and trabeculectomy group. Overall success was 71.4% vs. 73.3% (p = 0.850), and complete success was 62.9% vs. 62.2% (p = 0.954), respectively. XEN had lower rate of numerical hypotony than trabeculectomy. No serious complication occurred in either procedure group. Conclusion At 24 months, XEN showed a rate of success comparable to that of trabeculectomy. Although XEN had a higher final IOP than trabeculectomy, XEN achieved 32% IOP reduction, and achieved final IOP in mid-teen level. No serious complication occurred in either group. XEN can be applied for treatment of mild to moderate stages of glaucoma in Southeast Asian patients.

Efficacy of the XEN-Implant in Glaucoma and a Meta-Analysis of the Literature

Background: To assess the efficacy of XEN-implant surgery in patients with glaucoma, and to perform a meta-analysis of previously published results and compare these to our data. Methods: Prospective case-control study, in which all eyes that underwent XEN-implant surgery were included from 2015 onwards. Sub-analyses were performed for eyes that underwent XEN-implant as standalone procedure and as cataract-combined procedure. To compare our results, a systematic review was performed using the Embase, PubMed, Web of Science, and Cochrane database. Meta-analyses were performed by combining data (intraocular pressure (IOP), IOP-lowering medication, and complications) from the retrieved studies. Results: A total of 221 eyes underwent XEN-implant surgery (124 standalone and 97 cataract-combined). The mean ± standard deviation IOP declined from 18.8 ± 6.5 to 13.5 ± 4.3 mmHg at the last follow-up (p < 0.001; 28.9%). Postoperative, no significant differences in IOP or IOP-lowering medication were found between patients with and without combined procedure. Secondary surgeries were performed in 20.8% of eyes, most of them (63.0%) within six months. A meta-analysis of 19 studies retrieved from the systematic review showed a two-years postoperative pooled mean (weighted mean difference) of 14.5 (7.3) mmHg and 1.0 (1.6) for IOP and IOP-lowering medications, respectively (compared to 13.5 (5.3) mmHg and 3.2 (2.4) in the current study). Conclusion: XEN-implant surgery was effective and safe in lowering IOP and the number of IOP-lowering medications. There were no differences between standalone and combined procedures.

A novel surgical technique for the treatment of a filtration bleb extending over 180° after Xen gel stent implantation

Purpose: To describe a novel surgical treatment option for managing a symptomatic filtration bleb extending into the three quadrants with adequate IOP control after Xen gel stent implantation. Methods: A 62-year-old female with pseudoexfoliative glaucoma with an IOP of 34 mmHg underwent implantation of a Xen to reduce the IOP in her right eye. The IOP responded well to the procedure, but the patient developed a persistent giant filtration bleb with foreign body sensation and pain. A huge filtering bleb of over 180° after Xen implant surgery was managed by splitting the giant bleb into two parts, posterior dissection into the intermuscular space, a biodegradable collagen device implantation, and suturing the conjunctiva in two parts with absorbable and nonabsorbable sutures. Results: Before the operation for treatment of a giant bleb, the patient had an IOP of 12 mmHg, a best-corrected visual acuity (BCVA) of 20/40, corneal dellen, and no antiglaucoma medication. Following the bleb recession procedure, the IOP was 16 mmHg, BCVA improved to 20/20, there were no corneal dellen and the patient reported resolution of her bleb discomfort. The IOP and BCVA remained stable through 18 months of follow-up and no antiglaucoma medications or additional surgical procedures were required. Conclusion: The novel technique described here can be one option to treat this rare (over 180°) bleb formation after Xen Gel Stent implantation without adversely affecting IOP control.