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Glaucoma Ahmed Tube Shunt

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Title: Glaucoma Ahmed Tube Shunt
Author (s): Russell Swan, MD; Craig Chaya, MD
Date: 7/18/2016
Keywords/Main Subjects: Glaucoma; Tube Shunt
Secondary CORE Category: Glaucoma / Surgical Therapy for Glaucoma
Diagnosis: Glaucoma; POAG
Brief Description: This video demonstrates a standard surgical technique for Ahmed tube shunt at the University of Utah Moran Eye Center with Dr. Craig Chaya. Below is our standard protocol:

  1. Mark the superior and temporal conjunctiva
  2. Perform conjunctival dissection and ensure carried to bare sclera. Relaxing incisions should be made at 12 and 3 oclock (left eye) and 12 and 9 oclock (right eye)
  3. Blunt dissection into superior temporal subconjunctival space to create space for placement of shunt
  4. May use brimonidine soaked sponge for additional hemostasis
  5. Isolate lateral and superior rectus muscles and mark insertions
  6. Prime valve using 27 gauge cannula and tying forceps
  7. Deliver Ahmed plate into the superior temporal sub-Tenons space
  8. Mark sclera 7.0mm posterior to the limbus
  9. Pass 7-0 vicryl suture partial thickness through eyelet holes at anterior edge of place of tube
  10. Tie off tube with 7-0 vicryl suture (double loop so that the tube is not amputated)
  11. Ensure no flow through the tube
  12. Create wick suture through tube with 7-0 vicryl suture
  13. Create fenestration in tube anterior to wick suture. These two will help with IOP control in the immediate post op time period.
  14. Measure position of tube and cut bevel up with scissors
  15. Bend 23 gauge needle to use for entering the anterior chamber
  16. Mark 3.0mm posterior to the limbus in the location you wish the tube to enter (preferably superior)
  17. Create temporal paracentesis to have access to reform AC as needed
  18. Initiate partial thickness scleral tunnel with 23 gauge needle and rotate eye into neutral position. Try to enter the ac just anterior to the iris root so that the tube will not be against the cornea
  19. Flare scleral tunnel edge upon exit to make passage of tube easier
  20. Pass tube into scleral tunnel and into AC
  21. Use 7-0 vicryl suture to secure tube location with ‘X’ stitch
  22. Measure patch graft material and cut to size
  23. Secure anterior edge of patch graft with 7-0 vicryl suture
  24. Mobilize conjunctiva and Tenon’s over the tube and plate
  25. Close conjunctiva:
    1. Start with buried horizontal matress suture. Ensure episcleral bite to help prevent flap from slipping.
    2. Cut short end of suture and then use a running suture to close the relaxing incision
    3. Close the second relaxing incision in a similar fashion
    4. This can be done with the same 7-0 vicryl suture or a 10-0 vicryl suture

Tube Shunt Post-Op Guidelines




Format: video
Faculty Approval by: Craig Chaya, MD
Identifier: Moran_CORE_21536
Copyright statement: Russell Swan, MD, ©2016. For further information regarding the rights to this collection, please visit:
Attribution/citation suggestions:
Swan, R and Chaya, C. Glaucoma Ahmed Tube Shunt. Moran CORE. Available at: Accessed July 27, 2016.