NEW YORK (Reuters Health) – As a first-line operation for primary open-angle glaucoma, insertion of a Molteno drainage tube provides better control of intraocular pressure (IOP) than does trabeculectomy over the long term, the device’s developer reports.

Dr. Anthony C. B. Molteno and colleagues at the University of Otago Dunedin School of Medicine and Dunedin Hospital in New Zealand note in the Archives of Ophthalmology online July 11 that trabeculectomy became the standard drainage operation after it was introduced in 1968, while Molteno drainage tubes were initially used when additional risk factors compromised trabeculectomy results.

In the current paper, the authors describe outcomes of trabeculectomies and Molteno implants performed as the first drainage operation for cases of primary open-angle glaucoma at their hospital between 1976 and 2007. The prospective study includes 718 eyes in 500 patients who underwent primary trabeculectomy and 260 eyes in 195 patients who had primary Molteno implants.

Rates of IOP control at 21 mm Hg or less with or without hypotensive medication were 95% at 1 year, 82% at 10 years and 68% at 20 years in the trabeculectomy group; corresponding rates in the Molteno implant group were 98%, 96% and 91%, the team found.

Treatment failure, defined as an IOP greater than 21mm Hg, phthisis, re-operation, or total loss of vision due to early or late complications, occurred in 96 eyes (13%) in the trabeculectomy group and 8 (3%) in the Molteno implant group, according to the report.

“In summary,” Dr. Molteno and colleagues conclude, “insertion of a Molteno implant provided superior long-term IOP control to trabeculectomy when carried out as a first operation in cases of primary glaucoma.”

Reference:
Long-term Results of Primary Trabeculectomies and Molteno Implants for Primary Open-Angle Glaucoma
Arch Ophthalmol 2011.