Cornea for glaucoma shunt coverage

Glaucoma drainage devices require covering the tube with an allograft material, then
conjunctival advancement over the allograft to permit smooth over-glide by the eyelid.
Surgeons now enjoy a wide choice of biomaterials for shunt coverage, including cornea,
sclera, corneo-scleral rim, pericardium, fascia lata, amniotic membrane, dura mater, dermis,
and intestinal mucosa. Cornea has been used fresh, frozen, glycerol-preserved, and irradiated and stored in albumin. It is used as a split thickness graft, either by use of anterior caps remaining after DSAEK / DMEK preparation, or as split by the surgeon at the time of the procedure. Relative to other opaque biomaterials, cornea allows a cosmetically pleasing appearance, because it remains clear and thus is less visible over shunts placed in the inferior nasal quadrant. Tissue clarity also facilitates laser suture lysis and removal of stents after implantation of non-valve shunts.

References Cited

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