As the use of glaucoma drainage implants (GDIs) continues to expand in clinical practice, surgeons are becoming more attuned to postoperative considerations, including the risk of tube erosion. Kateki Vinod, MD, discussed the growing use of GDIs and the associated risk of tube erosion, a complication that remains a serious concern because of its link to vision-threatening infection, in a presentation at EnVision Summit 2026, held February 13 to 16 in Río Grande, Puerto Rico.¹ Vinod is associate professor of ophthalmology at the Icahn School of Medicine at Mount Sinai and New York Eye and Ear Infirmary of Mount Sinai.

In this Q&A conversation with the Eye Care Network, Vinod further detailed key risk factors, evolving preventive strategies, evidence-based management approaches, and the importance of long-term monitoring and interdisciplinary collaboration to optimize patient outcomes.

Note: Transcript edited for clarity and length.

What are the most common risk factors that contribute to tube erosion in glaucoma drainage devices, and are there any new strategies or surgical techniques that can help minimize these risks?

Kateki Vinod, MD: Recent Medicare claims data and surveys of glaucoma surgeons have shown that glaucoma drainage implant (GDI) surgery is being increasingly utilized in the US.^2,3 As a result, we are inevitably going to encounter more complications relating to GDI surgery, including tube erosion. Prior to the routine use of tissue patch grafts during GDI surgery, the rate of tube erosion was as high as 30%.⁴ Available patch graft materials now include sclera, pericardium, cornea, amniotic membrane, and collagen matrix. Recent landmark randomized clinical trials have shown tube erosion rates between 1% to 5% at 5 years postoperatively.^5-8

Although less frequent now, tube erosion is a significant complication of GDI surgery because it provides a nidus for microorganisms to enter the eye and cause endophthalmitis, a potentially vision-threatening intraocular infection. Risk factors for tube erosion include macrotrauma (eg, from eye rubbing), microtrauma (eg, from blinking), poor lubrication of the ocular surface, immunologic factors, neovascular glaucoma, serial anti-VEGF injections, and poorly fitting contact lenses. Surgical risk factors include an inferiorly located GDI, excessive conjunctival tension over the tube, prior conjunctiva-involving surgery (especially with antifibrotic use), and combining GDI surgery with other procedures.

Strategies to mitigate the risk of tube erosion include positioning the tube entry site into the anterior chamber at 12 o’clock for superotemporal tubes and 6 o’clock for inferonasal tubes as this avoids direct mechanical pressure on the tube from the upper and lower eyelid margin, respectively. In addition, creating a long (greater than 2 mm) scleral tunnel and using a patch graft to cover the tube entry site reduce the risk of tube erosion.

Once tube erosion is detected, what are the current best practices for management, and how do you decide between conservative versus surgical interventions?

Vinod: In the absence of an associated infection, management of tube erosion consists of immediate initiation of prophylactic broad-spectrum topical antibiotics. However, observation on antibiotics alone is an insufficient intervention. Prompt surgical repair is the only definitive solution for tube erosion due to the high risk of intraocular infection. Direct conjunctival closure is inadvisable as recurrence rates are high. Surgical technique consists of extensive conjunctival dissection, including over the endplate of the GDI, to sufficiently mobilize and advance healthy tissue to cover the site of tube erosion. Patch grafts will melt over time, and placement of a new patch graft at the time of surgical revision is important.

My preference is to use a corneal patch graft as it has a lower profile than sclera (which is helpful when working with thin or friable tissue) and offers improved cosmesis. If an anterior chamber tube is too temporal or nasal and has a high likelihood of recurrent conjunctival erosion due to its location, I will reposition the tube to 12 o’clock or 6 o’clock through a long scleral tunnel. Other options include repositioning the tube to the ciliary sulcus or pars plana if the eye is pseudophakic, as the more posterior entry site will allow for more complete coverage by the eyelid. Of course, repositioning to the pars plana requires a concomitant pars plana vitrectomy to avoid vitreous-tube occlusion. Conjunctival autografts obtained from another quadrant, amniotic membrane grafts, or rotational pedicle flaps may be required in cases where the conjunctiva cannot be advanced to completely cover the tube. In cases of recurrence despite prior attempts at surgical repair or when the tube erosion is large and/or involves the endplate, I generally remove the tube and either place a new GDI in a different quadrant or perform cyclophotocoagulation to maintain IOP control.

Beyond surgical technique and acute management, what long-term monitoring strategies and preventive measures are important to reduce the risk of tube erosion and related complications?

Vinod: It is important to closely examine every patient who has undergone GDI surgery at each clinic visit to ensure that the tube remains covered. Conjunctival thinning with loss of conjunctival capillaries overlying the tube should alert the surgeon to a higher risk of impending erosion. Patients should be extensively counseled regarding their lifetime risk of tube erosion and educated on the symptoms of intraocular infection as well as the need to seek immediate ophthalmic care should such symptoms develop.

Collaboration between glaucoma and vitreoretinal specialists is essential for patients with GDIs to reduce the risk of mechanical trauma from intravitreal anti-VEGF injections administered adjacent to the tube entry site.

Kateki Vinod, MD
E: [email protected]
Vinod is an associate professor of ophthalmology, Icahn School of Medicine at Mount Sinai, New York Eye and Ear Infirmary of Mount Sinai. Vinod has no financial disclosures.

References

1. Vinod K. Tube erosion. Presented at: EnVision Summit 2026; February 13 to 16, 2026; Río Grande, Puerto Rico.

2. Arora KS, Robin AL, Corcoran KJ, Corcoran SL, Ramulu PY. Use of various glaucoma surgeries and procedures in Medicare beneficiaries from 1994 to 2012. Ophthalmology. 2015;122(8):1615-1624. doi:10.1016/j.ophtha.2015.04.015

3. Vinod K, Gedde SJ, Feuer WJ, et al. Practice preferences for glaucoma surgery: a survey of the American Glaucoma Society. J Glaucoma. 2017;26(8):687-693. doi:10.1097/IJG.0000000000000720

4. Heuer DK, Budenz D, Coleman A. Aqueous shunt tube erosion. J Glaucoma. 2001;10(6):493-496. doi:10.1097/00061198-200112000-00010

5. Gedde SJ, Herndon LW, Brandt JD, et al. Postoperative complications in the Tube Versus Trabeculectomy (TVT) study during five years of follow-up. Am J Ophthalmol. 2012;153(5):804-814.e1. doi:10.1016/j.ajo.2011.10.024

6. Gedde SJ, Feuer WJ, Lim KS, et al. Postoperative complications in the Primary Tube Versus Trabeculectomy Study during 5 years of follow-up. Ophthalmology. 2022;129(12):1357-1367. doi:10.1016/j.ophtha.2022.07.004

7. Budenz DL, Feuer WJ, Barton K, et al. Postoperative complications in the Ahmed Baerveldt comparison study during five years of follow-up. Am J Ophthalmol. 2016;163:75-82.e3. doi:10.1016/j.ajo.2015.11.023

8. Christakis PG, Kalenak JW, Tsai JC, et al. The Ahmed Versus Baerveldt Study: five-year treatment outcomes. Ophthalmology. 2016;123(10):2093-2102. doi:10.1016/j.ophtha.2016.06.035