Researchers led by Swaminathan S. Swarup, MD, of Bascom Palmer Eye Institute set out to determine whether the addition of two 9-0 Nylon wicks in nonvalved drainage device procedures could have positive effects on lowering IOP and reducing the use of glaucoma medications. A retrospective review of all nonvalved aqueous shunt insertions completed by a single surgeon at Duke Eye Center was completed using current procedure terminology. Patients undergoing Baerveldt (Johnson & Johnson) or Clearpath (New World Medical) 350-mm² aqueous shunt insertion with fenestrations only (n=37) or fenestrations with 2 Nylon wicks were identified (n=92). All devices were ligated with 7-0 Vicryl (polyglactin) sutures, and either 4 fenestrations or 2 fenestrations and two 9-0 Nylon wicks were placed anteriorly to the ligature. Data regarding VA, IOP, number of glaucoma medications, and complications were collected from the preoperative visit just before surgery and at postoperative day 1, postoperative week 3 (POW3), postoperative week 5, and postoperative month 2 (POM2). The main outcome measures were VA, IOP, number of glaucoma medications, and complications at all postoperative time points.

There was no difference in logMAR VA between the 2 groups at any time point. At POW3, IOP was significantly lower in the wick group (14.6±7.7 mmHg vs 18.1±8.7 mmHg, P=.03). Number of glaucoma medications used was significantly reduced in the wick group at POW3 (0.5±0.9 vs 1.0±1.2, P=.02) and POM2 (0.7±1.0 vs 1.4±1.3, P=.02). There was no significant increase in the overall rate of complications in the wick group, but there was a higher rate of transient hyphema (28% vs.8%) and hypotony (33 % vs 19%) in the wick group. The researchers, who reported their findings in the Journal of Glaucoma, concluded that the use of 2 Nylon wicks with fenestrations in nonvalved aqueous shunt device implantation can significantly lower IOP and medication burden over the time that ligature sutures dissolve.