Trabeculectomy has been the most commonly performed glaucoma surgery for the past few decades. Even now, new glaucoma surgeries e.g. Xen45 and Preserflo , are compared to this gold standard. Earlier glaucoma surgeries include iridectomy (Albrecht von Graefe – 1857), trephine operation for glaucoma (Argyll Robertson – 1876), cyclodialysis with intraocular drainage (Leopold Heine -1905), Iridenclesis (Soren Holt – 1906), Corneo-scleral trephining (Robert Henry Elliot – 1909) and Goniotomy with a contact glass (Otto Barkan -1936).

Foundational work demonstrating the intraocular pressure lowering ability of filtration surgery begins with work by Louis de Wecker (1867). He described filtration by sclerotomy. A narrow knife was used to cut a full thickness incision through the upper sclera 1mm posterior to the limbus into the upper anterior chamber angle. Argyll Roberston, better known for his eponymous pupils, described a trephine operation (1876) for glaucoma where an anterior sclerotomy was made in the sclera to drain aqueous. Lagrange described a scleroiridectomy (1906) where uveal tissue was incarcerated in the wound to prevent the wound closing. Sugar also introduced iridencleisis (1906) where iris was incarcerated in the wound for a similar purpose. Robert Henry Elliott introduced the modern trephining operation, a sclero-corneal trephining (1909) for the treatment of glaucoma.

In 1962, Sugar introduced the concept of a guarded filtering surgery by describing limboscleral trephination which had fewer post operative complications compared to earlier full thickness filtering surgery.

In 1968, John Edward Cairns, assuming that in primary open angle glaucoma resistance was mainly in the trabecular meshwork and Schlemm’s canal, devised “trabeculectomy”. He devised a posterior hinged partial thickness corneo-scleral flap and excised a portion of trabecular meshwork and Schlemm’s canal. He then sutured the flap firmly. Drainage was supposed to occur through the opened Schlemm’s canal into the aqueous veins.

Peter Watson (1970) performed a trabeculectomy with a more posterior excision which excluded excision of Schlemm’s canal. He found that the results were similar to his Cambridge contemporary John Cairn’s technique. With his modification, the surgery was similar to the current trabeculectomy surgery we use today.

Technically speaking, the modern trabeculectomy is a misnomer. Largely now, no trabecular meshwork is excised. It is a guarded sclerokeratectomy.


SUGAR HS. Some recent advances in the surgery of glaucoma. Am J Ophthalmol. 1962 Dec;54:917-29. PMID: 13979103

Cairns JE. Trabeculectomy. Preliminary report of a new method. Am J Ophthalmol. 1968 Oct;66(4):673-9. PMID: 4891876.

Watson PG, Barnett F. Effectiveness of trabeculectomy in glaucoma. Am J Ophthalmol. 1975 May;79(5):831-45. doi: 10.1016/0002-9394(75)90745-x. PMID: 1146946.