Express Implant Versus Trabeculectomy After Late Failure Trabeculectomy

"Operative technique in group I (Express implant) was as in group II (trabeculectomy) except with no sclerectomy or peripheral iridectomy , the steps included conjunctival peritomy superior-temporally away from the site of the fibrotic bleb at 12 o'clock, placed on the episclera under the conjunctiva and Tenon's capsule for a contact time of 3 minutes, ,triangular scleral flap , scleral dissection forward to the clear cornea to allow exposure of scleral spur then creation of a pilot hole is fashioned using a sapphire blade (Alcon laboratories,USA) then Express shunt 3 mm long device and external diameter 400 microns was implanted followed by closure of scleral flap and conjunctiva.~While in group II, Trabeculectomy with Mitomycin-C was done in superior-temporal region away from the fibrotic bleb at 12 o, clock."