Combined argon laser peripheral iridoplasty and Nd: YAG laser shock wave therapy for recurrent XEN gel stent obstruction due to iris incarceration: A case report

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

Aim

This study was aimed to summarize the complications and their management associated with XEN gel stent implantation.

Methods

A systematic review of literature was conducted using Medline (via PubMed), EMBASE, the Cochrane Library databases, and China National Knowledge Infrastructure, from their inception to February 1, 2024.

Results

A total of 48 studies published between 2017 and 2024 were identified and included in the systematic review, including 16 original studies (retrospective or prospective clinical studies), 28 case reports, and 4 case series, which followed patients for up to 5 years. Early postoperative complications of XEN gel stent implantation include hypotony maculopathy (1.9-4.6%), occlusion (3.9-8.8%), suprachoroidal hemorrhage (SCH), choroidal detachment (0-15%), conjunctival erosion, and exposure of the XEN gel stent (1.1-2.3%), wound and bleb leaks (2.1%) and malignant glaucoma (MG) (2.2%). Mid-postoperative complications of XEN gel stent implantation included migration of XEN (1.5%), ptosis (1.2%), endophthalmitis (0.4-3%), macular edema (1.5-4.3%), hypertrophic bleb (8.8%) and subconjunctival XEN gel stent fragmentation (reported in 2 cases). Late postoperative complications reported in cases included spontaneous dislocation and intraocular degradation.

Conclusion

XEN gel stent implantation is a minimally invasive glaucoma surgery (MIGS) procedure for glaucoma, known for its potential to minimize tissue damage and reduce surgical duration. However, it is crucial to note that despite these advantages, there remains a risk of severe complications, including endophthalmitis, SCH, and MG. Therefore, postoperative follow-up and early recognition of severe complications are essential for surgical management.

Reviving XEN63 Gel Stent Patency in Uveitic Glaucoma: A Novel Approach Using 10-0 Nylon Probe

Purpose

This case report describes the possibility of XEN63 lumen obstruction at the middle of the device and emphasizes the potential to restore its flow using an ab-externo revision technique involving a 10-0 nylon suture probe, before considering more aggressive surgical interventions.

Methods

A 55-year-old female with uveitic glaucoma underwent XEN63 implantation but experienced elevated intraocular pressure (IOP) (35 mm Hg) 1 month after the operation, despite medical therapy. A flat bleb, lack of response to medication, yttrium aluminum garnet (YAG) laser treatment, and slit-lamp needling necessitated revision.

Results

An ab-externo surgical procedure was performed using a 10-0 nylon probe to release the obstruction, followed by the application of mitomycin C and removal of fibrous tissue and subconjunctival Tenon's capsule. Intraoperatively, flow was observed only after probing with the 10-0 nylon. Postoperatively, the patient's IOP decreased immediately and remained well-controlled at 2 months (8 mm Hg) without requiring further medication.

Conclusion

For patients experiencing increased inflammatory response, the XEN63 gel stent may develop deep lumen occlusion that is unresponsive to conventional treatments. This case report introduces a novel surgical technique applicable to various glaucoma devices, utilizing an ab-externo approach with a 10-0 nylon probe. The demonstrated success in reducing IOP suggests its potential as a less invasive alternative to consider before resorting to more aggressive surgical interventions.

How to cite this article

Marchese V, Randazzo V, Badalamenti R, et al. Reviving XEN63 Gel Stent Patency in Uveitic Glaucoma: A Novel Approach Using 10-0 Nylon Probe. J Curr Glaucoma Pract 2024;18(2):74-78.

Tube obstruction caused by intraocular lens capture following PreserFlo MicroShunt implantation

Purpose

We describe a rare case of tube obstruction caused by intraocular lens (IOL) capture following a PreserFlo MicroShunt (PMS) surgery and its subsequent management.

Observations

Tube obstruction was noted following PMS implantation at 8 days postoperatively. The intraocular pressure (IOP) increased to 42 mmHg because of tube occlusion that was caused by iris and IOL capture at the tip of the tube. The occlusion was released surgically to free the lumen, and the IOP rapidly decreased to 14 mmHg.

Conclusions and importance

IOP elevation due to tube obstruction caused by iris and IOL capture after PMS surgery was resolved by surgical intervention without tube reinsertion. Extra care is required regarding the IOL position in relation to the PMS tube when hypotony occurs in the early postoperative period.

Iris Obstruction Following PRESERFLO™ Microshunt Implantation and Surgical Management

PURPOSE

To present a case of lumen obstruction after implantation of microshunt with subconjunctival drainage and subsequent management.

CASE REPORT

A 56-year-old male with primary open angle glaucoma underwent uneventful PRESERFLO™ MicroShunt implantation in both eyes. Five months after surgery the patient presented with an intraocular pressure of 26▒mmHg in the right eye due to iris obstruction.

RESULTS

The iris fibers were severed and removed surgically to free the lumen. Follow-up showed a normalised intraocular pressure of 10▒mmHg and a free lumen.

CONCLUSION

Uncontrolled intraocular pressure due to iris obstruction following PRESERFLO™ Microshunt was addressed by surgical removal of iris fibers at the lumen entrance without the need for tube repositioning.

Iris-Occlusion of XEN Gel Stent following Ab Externo Transconjunctival Implantation Technique

The use of minimally invasive glaucoma surgery (MIGS) devices has become increasingly common for the management of elevated intraocular pressure (IOP) in the context of glaucoma. These technologies have traditionally been associated with fewer postoperative complications than conventional surgical techniques. However, we report on a rare case of transient XEN occlusion associated with pupil dilation following XEN gel stent implantation. This case highlights that in future XEN implantations, it may be preferable to position the XEN at a lesser angle to the iris to prevent such an occlusion. The use of different positionings of XEN is performed to optimize outcomes. However, it is highlighted that complications may arise in certain circumstances.