Conjunctival inflammation can lead to tube exposure after filtrating surgery
July 20, 2026

Conjunctival inflammation can lead to tube exposure after filtrating surgery

Tube exposure after glaucoma drainage device surgery is multifactorial; younger age is an established risk factor, while chronic ocular inflammation has also been associated with an increased risk (1). Prevention requires posterior tube positioning, avoidance of conjunctival tension, and adequate coverage with a scleral tunnel or patch graft (2). Processed bovine pericardium has been associated with inflammatory graft melt (3) and has shown higher tube exposure rates than donor sclera in comparative studies (4). Randomized evidence demonstrated significantly less graft thinning with amniotic membrane–umbilical cord grafts than with processed pericardium (5). Partial-thickness corneal grafts provide durable coverage, favorable cosmetic outcomes, and low long-term tube exposure rates, making them a safe alternative for tube coverage (6).


References

  1. Chaku M, Netland PA, Ishida K, Rhee DJ. Risk factors for tube exposure as a late complication of glaucoma drainage implant surgery. Clin Ophthalmol. 2016;10:547-553.
  2. Mostofian F, Armstrong J, Kherani I, Schlenker M. Management of Tube Exposure. EyeNet Magazine. 2024 Apr 1;:27-29
  3. Rogers C, Krishnan A, Choudhary A, Wiskart P. Bovine pericardium (Tutopatch) used to cover Ahmed valve tubing associated with severe conjunctival inflammatory melt. Invest Ophthalmol Vis Sci. 2008;49:E-Abstract 13.
  4. Van der Valk R, Webers CAB, Lumley T, et al. Donor sclera versus bovine pericardium as patch graft material in glaucoma implant surgery. J Glaucoma. 2018.
  5. Myers JS, Moster MR, Schwartz C, Schmidt CM, et al. Outcomes of the Shunt Tube Exposure Prevention Study (STEPS): A randomized clinical trial. Am J Ophthalmol. 2020;217:130-138.
  6. Spierer O, Waisbourd M, Golan Y, Newman H, Rachmiel R. Partial thickness corneal tissue as a patch graft material for prevention of glaucoma drainage device exposure. BMC Ophthalmol. 2016;16:20.


Contributor: Ligia Naranjo, MD, MSc. Hospital Universitari de Mataró, Spain


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