Baerveldt-Baerveldt Apposition: A New Surgical Technique to Salvage Obstructed Glaucoma Drainage Tubes.
Aim
Glaucoma drainage device (GDD) failure is usually rectified by the replacement of the entire device or using a tube extender, both of which were associated with postoperative complications. To minimize these risks, we developed a technique to replace the failing section of a tube while keeping the filtration plate in place, and without resorting to an extender clip.


Background
We describe the case of a 69-year-old man, whose left posttraumatic glaucoma was initially treated with a XEN-augmented Baerveldt procedure. Following recurrent obstructions, a kinked section of the Baerveldt tube was sectioned and replaced.


Technique
After sectioning the blocked section of the tube, a new Baerveldt tube was inserted into the anterior chamber. Its filtration plate was removed, and the posterior end of the new tube was connected to the anterior end of the existing device so that both lumens would be continuous. The adjoining tubes were stitched to each other with two 8-0 nylon sutures passing through the walls of the tubes. An allograft patch was replaced over the tubes and the conjunctival fornix was closed. Intraocular pressure (IOP) normalized immediately after surgery and remained stable through 6 months.


Conclusion
This surgical approach offers a new way to salvage a failing Baerveldt tube without replacing the filtration plate, repeating a complete surgery, or potentially compromising the conjunctiva with an extender. The minimal residual gap at the junction between the tubes appears to provide the same additional IOP-lowering effect as the "venting slits" that are sometimes performed to minimize the initial hypertensive phase without causing hypotony.


Clinical significance
This report illustrates a simple yet effective technique to replace the failing section of a GDD or lengthen a short GDD without replacing the entire device or using an extender clip, and thus minimizing the risks of complications.


How to cite this article
Gillmann K, Mansouri K, Bravetti GE, et al. Baerveldt-Baerveldt Apposition: A New Surgical Technique to Salvage Obstructed Glaucoma Drainage Tubes. J Curr Glaucoma Pract 2019;13(3):110-112.
['Gillmann|Kevin|K|', 'Mansouri|Kaweh|K|', 'Bravetti|Giorgio E|GE|', 'Mermoud|André|A|']
Obstruction Glaucoma Glaucoma drainage devices Extender Complications Blockage Clinical technique Erosion Refractory Revision