Ophthalmology Glaucoma

Volume 8, Issue 5, Supplement, September–October 2025, Pages S49-S57
Ophthalmology Glaucoma

Original Article
Glaucoma Surgery: From the Tried and True to the Novel and New

https://doi.org/10.1016/j.ogla.2025.06.009Get rights and content
The surgical options for managing glaucoma have expanded exponentially in recent years. Traditional glaucoma surgery includes trabeculectomy and tube shunt surgery. These procedures drain aqueous into the subconjunctival space, and they are highly effective at lowering intraocular pressure (IOP). Laser suture lysis and releasable sutures allow the surgeon to selectively increase outflow after trabeculectomy, and the ability to titrate IOP postoperatively is an advantage of trabeculectomy over other glaucoma procedures. Mitomycin C and 5-fluorouracil are adjunctive antifibrotic agents that have been shown to improve the success of trabeculectomy, but they also increase the risk of complications such as hypotony maculopathy and bleb-related infections. Tube shunts have been used with increasing frequency as an alternative to trabeculectomy. A silicone tube maintains the patency of the drainage fistula and shunts aqueous humor to an end plate. Devices with larger end plates produce greater IOP reduction, and the presence of a flow restrictor in valved implants serves to reduce the risk of hypotony-related complications. Minimally invasive glaucoma surgery (MIGS) is a newer group of nonbleb-forming procedures performed via an ab interno approach and involves minimal disruption of ocular tissues. Trabecular meshwork/Schlemm’s canal MIGS improve aqueous drainage through the conventional outflow system by stenting, dilating, or cutting/stripping the trabecular meshwork and inner wall of Schlemm’s canal. Suprachoroidal MIGS create a cyclodialysis and increase uveoscleral flow through a device that connects the anterior chamber and suprachoroidal space. The various MIGS procedures are frequently performed in combination with phacoemulsification in patients with mild to moderate open-angle glaucoma. Minimally invasive glaucoma surgery offers a more favorable safety profile than traditional glaucoma surgery, but MIGS are less effective in lowering IOP. A trade-off exists between safety and efficacy with all currently available glaucoma operations. Surgical innovation in glaucoma has provided surgeons with the opportunity to tailor the selection of a procedure to the individual patient. Multicenter randomized clinical trials have provided valuable information to guide the surgical care of glaucoma patients.

Financial Disclosure(s)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

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Section snippets

Traditional Glaucoma Surgery

Trabeculectomy was popularized by Cairns in the late 1960s.31 This procedure involves the creation of a conjunctival flap and dissection of a partial thickness scleral flap that overlies a limbal sclerostomy. The number and tension of sclera flap sutures controls the rate of filtration and resultant IOP. Use of releasable sutures or laser suture lysis allows the surgeon to selectively decrease IOP postoperatively, and the titratability of trabeculectomy is a clear advantage over other glaucoma

MIGS

The number of MIGS procedures continues to grow, and their use has become widespread among glaucoma and cataract specialists. Many MIGS procedures lower IOP by improving aqueous drainage through the trabecular outflow system.36 The juxtacanalicular trabecular meshwork has been identified as the site of greatest resistance to aqueous ouflow.37 This resistance can be overcome by bypassing the trabecular meshwork with placement of a stent or by cutting or removing tissue. Intraocular pressure

Glaucoma Surgery as Initial Treatment

Glaucoma surgery has historically been undertaken when additional IOP reduction is needed despite the use of maximum tolerated medical therapy and appropriate laser treatment. However, randomized clinical trials have suggested that initial surgical management has advantages over initial medical treatment. The Moorfields Primary Treatment Trial assessed the relative efficacy of medical therapy, laser trabeculoplasty, and trabeculectomy without an antifibrotic agent as primary treatment in 168

Conclusions

The American Glaucoma Society has experienced a transformation over its 40-year history. The glaucoma surgical landscape has similarly evolved during the same time period. The expansion of surgical options for managing glaucoma has provided surgeons with the opportunity to tailor the selection of an operation to the individual patient. Comparative studies with long-term data are needed to fully evaluate newer glaucoma procedures. Future surgical innovation should address the trade-off between

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    • Disclosure(s):
    All authors have completed and submitted the ICMJE disclosures form.
    The author has made the following disclosures:
    L.W.H.: Consultant – Alcon, Abbvie, Balance Ophthalmics, Bausch and Lomb, Elios, New World Medical, Glaukos, Iantrek, Implandata, Myra Vision, Sight Sciences; Honoraria – Alcon, AbbVie, Balance Ophthalmics, Sight Sciences, Glaukos, Iantrek, New World Medical; Participation on a Data Safety Monitoring Board or Advisory Board – AbbVie, Balance Ophthalmics, Glaukos, Iantrek, Implandata, Sight Sciences, New World Medical; Stock or stock options – Balance Ophthalmics, Sight Sciences. HUMAN SUBJECTS: Human subjects were not included in this study. This article does not constitute human subject research. Therefore, institutional board review and informed consent are not required. This study adheres to the Declaration of Helsinki.
    No animal subjects were used in this article.
    Author Contributions:
    Conception and design: Gedde, Herndon
    Data collection: Gedde, Herndon
    Analysis and interpretation: Gedde, Herndon
    Obained funding: N/A
    Overall responsibility: Gedde, Herndon
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