XEN Gel Stent Failure Due to Luminal Obstruction.

Purpose: To discuss four cases of post-operative XEN gel stent luminal obstruction in patients with primary open angle glaucoma.

Case report: Four eyes in three patients with primary open angle glaucoma who received XEN stent implantation were found to have luminal obstruction of their stents. Stent obstruction can mimic filtering bleb failures not responding to bleb needling and antimetabolite injections. These obstructions were suspected to result from fibrin clots, iris pigment granules, or breakdown products of intraocular inflammation or hemorrhage. Treatment options trialed in these patients included bleb needling, 5-fluorouracil injection, and YAG laser to the proximal end of the XEN. Ultimately, all four eyes required XEN explantation and alternative filtering surgery.

Conclusion: XEN luminal obstruction is an important complication of stent placement that can ultimately lead to stent failure. Conservative measures such as laser or traditional bleb management may be considered before stent explantation or additional glaucoma surgery.