Graft-free glaucoma drainage device implantation: Short tunnel small flap technique

To introduce a new technique of short tunnel small flap graft-free glaucoma drainage device implantation and report our early experience.

In a retrospective study, patients with uncontrolled primary open-angle glaucoma underwent short tunnel small flap graft-free Ahmed glaucoma valve implantation. In this technique, plate is sutured 8-10 mm posterior to the limbus and a partial thickness flap is made at 1 or 11 o'clock position, 1 mm posterior the limbus. Tube was passed through a tunnel immediately anterior to the plate into the proximal edge of the flap and then inserted into the anterior chamber via a route underneath the flap. Flap then covered the distal end of the tube and conjunctiva was sutured. Patients were followed for a minimum of 12 months for any sign of tube exposure and rise of intraocular pressure.

A total of 16 consecutive patients with refractory primary open-angle glaucoma and uncontrolled intraocular pressure were included in this study. Mean age of participants was 59 ± 8.3 years and nine (56%) were male. Mean intraocular pressure at the time of presentation was 26 ± 6.2 mm Hg, which dropped to 16 ± 4.5 at 12 months postoperative follow-up. The number of medications at baseline was 3 ± 1 eye drops, which was decreased to 1 ± 1.2 at 12 months. There were no conjunctival and flap-related complications or any sign of tube exposure during 1-year postoperative period.

Short tunnel small flap graft-free glaucoma drainage device implantation technique combines advantages of both tunneling and flap techniques. Also, it may result in better tube positioning and more favorable cosmetic outcomes.