Pediatric glaucoma is a rare but potentially blinding condition that presents unique clinical challenges. The category includes a wide range of disorders—from primary congenital glaucoma to secondary glaucoma associated with ocular or systemic abnormalities that may be present at birth or develop later in life. Surgical intervention is typically the mainstay of treatment because medical therapy alone is often inadequate for sustained IOP control.

The current first-line surgical approach is angle surgery, either goniotomy or trabeculotomy. Reported success rates for goniotomy range from 30% to 90%, depending on factors such as the patient’s age and disease severity and the surgeon’s experience.1-5 Trabeculotomy is the preferred approach in eyes with cloudy corneas or a history of failed angle surgery. Circumferential trabeculotomy, a more extensive technique, has shown higher success rates than traditional trabeculotomy, with up to 90% IOP control maintained for 4 years.6-8

Unfortunately, approximately 20% of angle surgeries eventually fail, necessitating additional intervention.9 When angle surgery is unsuccessful or unsuitable, such as in patients with extensive scarring or syndromic glaucoma, subconjunctival filtration procedures can play an important role. This article focuses on trabeculectomy, glaucoma drainage implants (GDIs), and the Xen Gel Stent (AbbVie), with an emphasis on outcomes and complications in the pediatric population.

TRABECULECTOMY

Historically, trabeculectomy with adjunctive mitomycin C has been employed for the treatment of pediatric glaucoma, especially in patients who have a history of failed angle surgery. Trabeculectomy’s success, however, is tempered by children’s aggressive healing response, which often leads to subconjunctival fibrosis and bleb failure.

The long-term success rates reported for trabeculectomy in pediatric patients vary significantly. Sidoti et al reported success rates of 82%, 59%, and 59% at 12, 24, and 36 months, respectively, with no significant difference between primary and secondary glaucomas.10 Complications included late bleb-related infections (17%), hypotony, bleb leaks, and phthisis. Despite these risks, trabeculectomy remains a viable option in select patients, particularly when GDIs and the Xen may not be available.

GLAUCOMA DRAINAGE IMPLANTS

GDIs have largely supplanted trabeculectomy owing to their higher success rates in children, but each device has a unique risk profile.

The Ahmed Glaucoma Valve (AGV; New World Medical) is frequently used in children because its flow-restrictive design decreases the risk of early hypotony. Several studies have reported an initial success rate with the AGV of around 80% to 90%, but this has often precipitously declined at 24 months and beyond.11,12

Compared to the AGV, the Baerveldt Glaucoma Implant (BGI; Johnson & Johnson Vision) has a larger end plate. That feature combined with a nonvalved design allow the BGI to offer a lower IOP than the AGV, but the BGI carries a higher risk of early postoperative hypotony. A retrospective study by Budenz et al reported success rates of 67% and 60% at 2 and 8+ years, respectively, in pediatric eyes.13

Since its market launch in 2019, the Ahmed ClearPath (New World Medical) has emerged as an alternative in pediatric patients. This flexible silicone device has a lower profile than the AGV, and the ClearPath’s biocompatible materials and broad end plate may offer anatomic advantages in small orbits. An early case report documented a success rate of nearly 80% at 4 years.14 Pediatric-specific data, however, are limited.

XEN GEL STENT

The Xen Gel Stent is a 6-mm gelatin-based implant inserted ab interno or ab externo to create a subconjunctival filtering bleb. The device has gained popularity in adults, but its use in pediatric patients remains off-label and relatively uncommon. Published data on the Xen’s use for the treatment of pediatric glaucoma are scant.

A small retrospective series by Smith et al reported on three children who underwent Xen implantation. Two of the patients had a history of a failed trabeculotomy. The device was implanted as a primary procedure in the third patient. After 24 months, the IOP was well controlled in all three eyes without a need for medical therapy.15 In addition, forthcoming data from the Glaucoma Associates of Texas suggest that the Xen may have a role in the treatment of pediatric glaucoma, with multiple patients observed for greater than 5 years (unpublished data, 2025).

Key barriers to the Xen’s use in pediatric glaucoma include children’s greater fibrotic response compared to adults; the smaller anatomy and more elastic sclera of pediatric eyes, which make positioning the device more challenging; and limited long-term data, especially regarding device migration and occlusion. Nonetheless, in pediatric eyes with a history of failed angle surgery, the Xen might offer a less invasive approach to attempt before proceeding with a GDI.

CONCLUSION

Surgical decision-making in pediatric glaucoma is highly individualized. Important factors include the patient’s age, healing response, surgical history, anatomic abnormalities, and lens status (phakic, aphakic, or pseudophakic) as well as primary versus secondary glaucoma diagnosis.

Angle-based procedures are preferred initially, but subconjunctival surgeries remain a cornerstone in the management of pediatric glaucomas. GDIs have largely supplanted trabeculectomy owing to their higher success rates in children, but these devices are not without risk. Data on the Xen Gel Stent in pediatric eyes are lacking, but the device may be worth considering before proceeding to GDI surgery.

Continued research, individualized surgical planning, and multidisciplinary care are the keys to improving outcomes in this vulnerable population.

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