Generation 1 iStent occlusion in angle closure glaucoma as a reason for postoperative intraocular pressure spike treated using non-interventional methods.

This case reports the behaviour of a first-generation iStent implant in angle closure glaucoma. A primary angle closure glaucoma patient with a cataract and baseline intraocular pressure (IOP) of 31 mm Hg underwent phacoemulsification with an iStent implant. After an uneventful initial postoperative course, a sudden IOP spike was noted 5 days postoperatively.Careful gonioscopy revealed an obstructed stent lumen due to peripheral iris incarceration. A simple non-invasive method of relieving the occlusion was tried, using pilocarpine 2% eye drops in the clinic, following which there was successful normalisation of IOP and relief of occlusion.The propensity for stent occlusion is higher in primary angle closure disease and should be routinely monitored. A prophylactic use of pilocarpine in the early postoperative period can help reduce this risk. The patient remained medication-free till the last follow-up of 6 months with a significant IOP reduction of 48%.