Nonpenetrating glaucoma surgery cannot achieve lower target IOP

Nonpenetrating glaucoma surgery has little potential to reduce intraocular pressure (IOP) values, according to a study published in the March issue of the Journal of Glaucoma.

Ahmet Hondur, MD of Dinar State Hospital, Turkey and colleagues assessed the impact of nonpenetrating surgery on IOP by reviewing studies on nonpenetrating glaucoma surgery, deep sclerectomy (DS) and viscocanalostomy (VC) (excluding those reporting on combined glaucoma and cataract surgery) from the past five years.

Following primary DS, DS with implant, DS with antimetabolite, primary VC and VC with implant or antimetabolite, cases achieving IOP of ≤21 mmHg were 48.6%, 68.7%, 67.1%, 51.1% and 36.8%, respectively. The research team determined effectiveness in terms of target IOP achievement. For lower set IOP targets, DS and VC success rates were 35 – 86% and 10 – 67%, respectively.

Based on these data, the team concluded that the potential of nonpenetrating surgery to achieve lower target IOPs is low, although this type of surgery can reduce IOP into the high teens.