Recanalization of XEN-45 gel stent occlusion with cortical material after phaco-XEN surgery using Nd: YAG laser treatment: A case report

INTRODUCTION: The XEN Gel Stent (Allergan Inc., CA, USA) has been widely used in minimally invasive glaucoma surgery to lower intraocular pressure considering reasonable efficacy and safety profiles. However, the XEN gel stent could be occluded by fibrin, blood clots, or the iris due to its small lumen design for preventing postoperative hypotony. To date, only a few studies have assessed XEN occlusion after combined phacoemulsification with XEN gel implantation and how to manage this condition. We describe the first case report of XEN gel stent obstruction by cortical material, demonstrated by anterior segment optical coherence tomography (AS-OCT), which resolved effectively after low-energy neodymium-doped yttrium aluminum garnet (Nd: YAG) laser shock wave treatment. PATIENT INFORMATION: A 76-year-old Korean male patient underwent uncomplicated phaco-XEN-gel stent implantation and presented with low intraocular pressure (IOP) with a well-functioning filtering bleb during the first postoperative 4 days. On postoperative day 5, the XEN lumen was occluded by the cortical material, with an intraocular pressure elevation of 28 mm Hg. Slit-lamp examination revealed that cortical material was causing a block into the internal ostium of the XEN gel implant. AS-OCT examination also demonstrated the presence of hyper-reflective materials at the intraluminal portion and peritubular portion around the internal ostium of the XEN gel implant. DIAGNOSIS: XEN gel stent occlusion with cortical material after Phaco-XEN surgery. INTERVENTIONS: Low-energy Nd: YAG laser shock wave treatment. OUTCOMES: The IOP dropped from 28 mm Hg to 8 mm Hg immediately after treatment. Transient hypotony and a slightly shallow anterior chamber were noted over the 3 days after YAG laser treatment. The IOP continued to be well-controlled until 3 months later (range; 6 - 12 mm Hg). CONCLUSIONS: To the best of our knowledge, this is the first case report on the efficacy of Nd: YAG laser treatment for recanalization of XEN implant occluded by the cortex. Moreover, AS-OCT could provide additional clinical information for recanalization of the XEN gel stent.