Schlemm's Bidirectional Fluid Wave and Luminal Blood Reflux as Novel Intraoperative Signs Confirming Optimal...

Trabecular micro-bypass devices (TBDs) such as the iStent series (Glaukos Corporation), are effective in reducing intraocular pressure (IOP). However, precise placement of TBDs is crucial in achieving surgical efficacy, as device malpositioning may lead to suboptimal IOP reduction. We demonstrate 2 novel intraoperative signs to aid confirmation of accurate iStent placement, without reliance on imaging technologies.

Surgical technique report with video accompaniment.

Two intraoperative clinical signs that confirm optimal iStent placement are described: (1) Luminal Blood Reflux-achieved by gently decompressing the anterior chamber, with or without flushing of the stent lumen with balanced salt solution (BSS), thereby confirming stent positioning in the Schlemm canal (SC). (2) Schlemm's Bidirectional Fluid Wave (SBFW)-observable when flushing with BSS, suggesting fluid movement in the canal segments adjacent to the iStent device, thereby confirming stent patency and positioning in the SC.

The identified signs are useful, feasible, and reproducible indicators of accurate iStent placement. Future studies may evaluate the application of these confirmatory maneuvers in diverse clinical contexts and further establish a correlation with clinical outcomes.