Tied Tube Trial in Glaucoma Surgery
The aim of this study is to assess whether delaying early flow through the Ahmed tube shunt may improve the post-operative surgical outcomes and provide a more predictable outcome. To assess this the investigator will conduct a, randomized prospective, multi-centered study with collaborators at WashU in St. Louis, Duke University, Indiana University and the University of Pittsburgh. Participants will be randomized to have an AGV placement with tube ligation (no-early flow) and without ligation (allowing for early flow). IOP will be measured at day one, week one, and months, one, three six, and twelve. Additionally, clinical data regarding number of glaucoma medications, and complications post-operative complications will also be collected.
|Condition or Disease
The purpose of this study is to compare the post-operative surgical outcomes and complication rates in patients with different surgical techniques in the Ahmed FP7 glaucoma valve implant (New World Medical, Inc., Rancho Cucamonga, CA). In particular, the investigator wishes to assess whether delaying early aqueous flow by using a vicryl ligature (as done in most non-valved glaucoma drainage device implantation) will reduce the hypertensive phase, reduce early encapsulation, and optimize healing dynamics to allow for improved long term IOP results compared to standard implantation techniques.
Aggressive early aqueous flow may introduce inflammatory mediators that may increase fibrosis during wound healing. Furthermore, mechanical compression of the tissue surrounding the plate may further lead to a denser capsule and limit aqueous diffusion through Tenon's and conjunctiva. For these reasons, the investigator postulate's that the limitation of early aqueous flow through the Ahmed valve will reduce the rates of hypertensive phase, lead to a thinner and less encapsulated bleb, reduce complication rates such as hypotony, and lead to overall improvement in long-term IOP reduction.
Arms and Interventions
Procedure: Standard Implantation
Traditional Ahmed plantation without vicryl ligature
|Tied off Tube
Tied off Tube
Procedure: Tied off Tube
Ahmed implantation with vicryl ligature
Primary Outcome Measures
- IOP Change [Months 1, 3 , 6, and 12]
Secondary Outcome Measures
- Medication Change [Months 1, 3, 6, and 12]
Change glaucoma medications
Other Outcome Measures
- Complication Rate [Months 1, 3, 6, and 12]
Change Hypotony, Reoperations, Significant Vision Loss
- Surgical Case Time [Post op day 0]
Decrease surgical case time
- Capsule Thickness as measured by anterior segment OCT [month 6]
Capsule Thickness as measured by anterior segment OCT
Subjects with age at screening ≥ 18 years
Inadequately controlled glaucoma or ocular hypertension
Ahmed valve implant as the planned surgical procedure
Patients with primary glaucomas (Primary Open Angle Glaucoma or Primary Angle Closure Glaucoma) or pseudoexfoliation, pigmentary and traumatic glaucoma with or without a previous failed trabeculectomy or other intraocular surgery.
Primary tubes included
Investigators to recruit consecutively all eligible patients from their clinics.
Capable and willing to provide consent
Subjects with NLP vision
Subjects unable/unwilling to provide informed consent
Unavailable for regular follow up
Previous cyclodestructive procedure
Prior scleral buckling procedure or other external impediment to drainage device implantation
Presence of silicone oil
Vitreous in the anterior chamber sufficient to require a vitrectomy
Patients with pathology that may cause elevated episcleral venous pressure
Procedure combined with ocular surgery other than cataract surgery (i.e. combined tube-cataract surgery is okay)
Any abnormality other than glaucoma in the study eye that could affect tonometry.
Contacts and Locations
Sponsors and Collaborators
- Washington University School of Medicine
- American Glaucoma Society
- University of Pittsburgh
- Principal Investigator: James Liu, MD, Washington University St. Louis MO
Study Documents (Full-Text)None provided.