Conventional Non-Penetrating Deep Sclerectomy Versus Modified Subflap Mattress Suture in OAG

The surgical protocol for Non-Penetrating Deep Sclerectomy (NPDS) begins with standardized aseptic preparation using 10% and 5% Betadine, followed by peribulbar anesthesia. In the standard Group 1 procedure, a 4 mm x 4 mm superficial scleral flap is created after conjunctival dissection, and Mitomycin-C (0.2 mg/mL) is applied for two minutes to inhibit scarring. The core of the surgery involves dissecting a deeper scleral flap to 90% thickness, unroofing Schlemm's canal to expose the trabeculo-descemet's membrane (TDM) and allow for aqueous percolation. The deep flap is then excised, the superficial flap is sutured with 10/0 nylon, and the conjunctiva is closed with watertight 7/0 Vicryl sutures. For Group 2, the standard NPDS steps were followed until the excision of the deep scleral flap, at which point a specific mattress suture modification is introduced. Utilizing the Abdel Rahman and Habib technique, a 10/0 nylon suture is threaded through the sclera 2 mm lateral to the flap borders in an anteroposterior and postero-anterior fashion, creating a mattress configuration beneath the superficial flap to maintain the filtration space. Postoperatively, both groups follow a strict regimen of topical moxifloxacin and prednisolone acetate, which is tapered over six weeks, alongside a five-day course of oral ciprofloxacin to prevent infection and manage inflammation.