Tenon Cyst Patch Graft for Ahmed Glaucoma Valve Tube Exposure: Case Series Report

Abstract

Purpose: To report our experience using a Tenon cyst autograft in the management of tube exposure post Ahmed glaucoma valve (AGV) implantation. Methods: This is a retrospective case series. Results: Four patients who underwent tube exposure repair using Tenon cyst autograft were identified in our tertiary care center. The duration between initial AGV implantation and tube exposure ranged between 3 and 36 months with a mean of 16 months (±14.35 mo). All patients were followed postoperatively for a range of 4 to 24 months with a mean of 11.75 months (±9.03 o) and all remain exposure free at last follow-up. Conclusion: The use of a Tenon cyst autograft for the surgical repair of a tube exposure is valuable, as it involves using autologous scar tissue that is available in eyes that have undergone AGV implantation. The patch autograft is technically easy to harvest, and represents a significantly lower cost when compared with other available options.

Ahmed Glaucoma Valve Implantation to Reduce Intraocular Pressure: Updated Perspectives

“… 70 Using a Tenon cyst patch graft is another option for the surgical repairing of the tube exposure. 79 In this approach Tenon tissue harvested around the plate is used for the tube coverage.…”

Glaucoma drainage implant exposure: A review of aetiology, risks and repair considerations

“…Some authors have suggested using a different type of patch graft from initial surgery in cases of graft melt where there may be an underlying immunological reaction leading to the melt 34 . The type of grafts used for tube exposure repair include full thickness donor sclera, 15 split‐ thickness scleral flap, 54,55 cornea, 56 conjunctival pedicle flaps, 57,58 amniotic membrane, 59 donor acellular dermis, 60 buccal mucosa, 61 fascia lata, autologous tragal perichondrium patch graft, 62 tenon cyst patch graft, 63 and synthetic materials such as Ologen® 64 . Grover et al studied the safety and efficacy of forniceal conjunctival pedicle flap repair for conjunctival‐deficient tube erosions and in their retrospective study, none of their patients (15 eyes from 14 consecutive patients) had recurrence of tube erosion (mean follow‐up period was 49 months) 58 .…”

“…Tenon cyst formation around implant is not an uncommon finding following GDI surgery and Alvarez‐Ascencio et al described excising the tenon cyst or capsule around the GDI plate and using it as an autograft to cover the exposed area. None of their four patients had re‐exposure at the end of follow‐up (patients were followed postoperatively for a range of 4–24 months, with a mean of 11.75 months) 63 . In a case series of eight patients who underwent tube revision surgery due to exposed tubes from conjunctival defects, successful and lasting closure of all eight conjunctival defects with Ologen® was achieved without any side effects or complications (follow‐up of 12–42 months).…”