Safety and Efficacy of Ab Interno XEN 45 Gel Stent in Patients with Glaucoma and High Myopia

Abstract

This study reports on the safety and efficacy of Xen 45 in patients with glaucoma and high myopia. It was a retrospective study including patients with high myopia (>6D) who underwent Xen implant with 2 years of follow-up. The primary outcome was to report the incidence of hypotony (IOP ≤ 5 mmHg) and hypotony-related complications. Patients with high myopia treated with mitomycin-C-augmented trabeculectomy were included as a control group. We included 14 consecutive patients who underwent Xen implant (seven eyes) and trabeculectomy (seven eyes). The mean myopia was −14.71 ± 5.36 and −15.07 ± 6.11 in the trabeculectomy and Xen groups, respectively (p > 0.05). The success rate and the mean IOP at 1 and 2 years from the intervention were statistically comparable between the two groups. The group undergoing trabeculectomy showed a higher incidence of hypotony (six eyes (85.71%) vs. two eyes (28.57%)) and hypotony maculopathy (three eyes (42.86%) vs. zero eyes (0%)) and required more postoperative procedures. Patients with high myopia were at higher risk of hypotony-related complications after trabeculectomy. The Xen implant can achieve an IOP control comparable to trabeculectomy with a significantly better safety profile and can be considered as an option for the management of patients with high myopia and glaucoma.

Effectiveness and Safety of Xen Gel Stent in Glaucoma Surgery: A Systematic Review of the Literature

“…There are two studies that assessed the efficacy and safety of XEN in patients with high myopia. The results of both studies have pointed in the same direction, clearly indicating that the XEN device is an effective and safe option in patients with high myopia [ 105 , 106 ].…”

“…Evidence surrounding the use of XEN45 in myopic OAG patients is limited [ 52 , 64 , 104 , 105 , 106 ]. In fact, there are currently only two studies that specifically evaluated the efficacy and safety of XEN45 in patients with high myopia.…”

“…Sacchi et al [ 105 ], in a retrospective study (which included seven eyes followed for 2 years) evaluated the effectiveness and safety of Xen 45 in patients with medically uncontrolled glaucoma and concomitant high myopia (>6 Diopters). Preoperative mean IOP was significantly lowered from 22.1± 4.9 mmHg to 14.8 ± 4.0 mmHg at month-24, p < 0.0001.…”

“…Regarding safety, two eyes had hypotony (without maculopathy) and one eye had choroidal detachment [ 106 ]. According to the results of this study, the XEN implant had a better safety profile than trabeculectomy, with a similar hypotensive profile [ 105 ].…”

Complications of XEN gel stent implantation for the treatment of glaucoma: a systematic review

“…Several risk factors for hypotony after glaucoma surgery have been identified, including myopia, young age, the use of antimetabolites, pre-existing inflammation, aphakia, and old age accompanied by a thin conjunctiva and thinner central corneal thickness ( 36 – 38 ). Patients with high myopia are at a higher risk of developing ocular hypotony due to their thin scleral wall, which may result in potential leakage of aqueous humor from the scleral incision adjacent to the site of XEN gel stent insertion ( 39 ). Treatment options for hypotony after glaucoma surgery, mainly caused by over-filtrating blebs, include conservative management with topical autologous serum ( 40 ), transconjunctival compressive sutures ( 18 ), bleb injection of autologous blood ( 41 ) or viscoelastic material ( 42 ), as well as AC injection of viscoelastic material ( 43 ) or gas ( 44 ).…”