Triamcinolone for Ahmed Glaucoma Valve
Condition: Glaucoma
MeSH terms: Glaucoma
Study type: Interventional

Summary: 
      This triple-blind, stratified, randomized clinical trial includes 100 eyes of 100 patients
      aged 18 to 85 years with refractory glaucoma. Eligible subjects undergo stratified block
      randomization; eyes are first stratified to one of four subgroups: group 1:patients with
      previous failed trabeculectomy, group 2: uveitic glaucoma, group 3: neovascular glaucoma and
      group 4: other indications like aphakic glaucoma or glaucoma associated with vitreoretinal
      procedures.

      In each subgroup, eyes are randomly assigned to the study arms using random blocks:
      conventional Ahmed Glaucoma Valve (AGV) implantation (group A, 50 eyes), Ahmed Glaucoma Valve
      (AGV) with intraoperative periplate triamcinolone injection (group B, 50 eyes).

      Patients will be followed for one year. They will undergo full ophthalmology examination at
      first day, first week, month 1, 3, 6, 9 and 12 after the surgery.

      The primary outcome measure is cumulative probability of success, defined as intraocular
      pressure (IOP) of 6-21 mm Hg, with or without medication, and no serious complications,
      additional glaucoma surgery, or loss of light perception.

      The outcomes will be compared between two arms in each subgroup.

      The number of eyes requiring medications, time to initiation of medications, and number of
      medications will be compared.
    

Detailed description: 
      All procedures was performed by glaucoma specialists under general anesthesia employing the
      same technique in all subjects. The surgical field was prepared and draped in the usual
      sterile fashion. After insertion of a lid speculum and irrigation with povidine iodine 5%
      solution, a 7-0 silk limbal traction suture was placed to rotate the globe and achieve
      optimal supratemporal exposure. A limbus-based conjunctival peritomy was created 4mm
      posterior to the limbus and Tenon's capsule was dissected using Westcott and Stevens
      scissors. Hemostasis was achieved using wet field bipolar cautery. The Ahmed Glaucoma Valve
      (AGV) plate was secured to the sclera 8 mm posterior to the limbus with two interrupted 7-0
      silk sutures. The tube was trimmed to an appropriate length with the bevel facing anteriorly
      and inserted into the anterior chamber through a corneoscleral track created with a 23-gauge
      needle. The tube was fixed to the episclera with a 10-0 nylon mattress suture. A quadrangular
      donor scleral patch graft (4×7 mm) was fashioned to cover the exposed part of the tube and
      was secured to the sclera using 10-0 nylon sutures. At this stage, in adjunctive
      triamcinolone group, 10 mg triamcinolone was injected in the subtenon space around the Ahmed
      Glaucoma Valve (AGV) plate. The conjunctiva and Tenon were closed using 10-0 nylon suture in
      a running fashion. At the end of the procedure, a subconjunctival injection of 4 mg
      betamethasone and 50 mg cephazolin were given in all eyes.

      All patients were examined on the first post-operative day; the postoperative regimen
      included topical chloramphenicol 0.5% eye drops 4 times per day for 1 week and topical
      betamethasone 0.1% eye drops 6 times per day which was tapered over 6 to 8 weeks, except in
      cases with severe inflammation which required a longer period of treatment.

      Follow up examination was repeated every week during the first month and thereafter at 6
      weeks, and 3, 6, 9 and 12 months after the operation. Possible complications such as
      endophthalmitis, choroidal effusion or hemorr, wound leakage, hyphema, hypotony, malignant
      glaucoma, implant exposure, tube malposition, bleb encapsulation, and decreased best
      corrected visual acuity (BCVA) more than 2 lines were mentioned. IOP was measured by a
      calibrated Goldmann applanation tonometer (SN-9007, Haag-Streit, Koniz, Switzerland). All
      measurements were obtained by one masked examiner.

      The main outcome measure of the study was intraocular pressure and number of anti-glaucoma
      medications. Complete success was defined as IOP between 6 and 21 without the use of any
      glaucoma medication. Partial success was defined as IOP between 6 and 21 with a maximum of 2
      glaucoma drops. Overall success rate was the sum of complete and partial success rates.
      Failure was defined as IOP>21, IOP<21 with ≥3 medications, loss of vision, shunt extrusion
      and need for additional glaucoma surgery. Other outcome measures included best corrected
      visual acuity (BCVA), number of glaucoma medications, and complications.
    

Intervention name(s): Adjunctival Triamcinolone
Intervention type(s): Drug
Intervention description(s): Intraoperative Periplate 10 mg Triamcinolone Injection during AGV Implantation
Other intervention name(s): Intraoperative steroid
Intervention MeSH terms: Triamcinolone
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Steroid, Triamcinolone, Ahmed Glaucoma valve