Istent-W In Glaucoma Secondary To Corneal Transplantation Surgery

We analyzed a series of 6 corneal transplant cases who developed post-surgical ocular hypertension (OHT) or glaucoma and were implanted with the iStent-W device.

Analysis on 6 patients who had undergone corneal transplantation surgery, 4 penetrating keratoplasty (PK) and 2 Descemet membrane endothelial keratoplasty (DMEK). Although none of them had previously been diagnosed with OHT, all patients developed OHT within one year after the corneal transplantation surgery and 2 of them glaucoma. 

All patients were on hypotensive treatment with 3 drugs (including prostaglandin) and 2 of them were also on acetazolamide 250 mg every 8 hours. We consider poor intraocular pressure (IOP) control to be pressures greater than 25 mmHg with maximal treatment, or progression of optic nerve excavation. The surgical procedure used in all 6 cases was implantation of GlaukosR iStent inject-W, in two of them associated with cataract surgery. We analyzed the decrease in IOP, as well as intraoperative complications. Endothelial damage was also evaluated by means of previous and post-surgical endothelial cell counting.

In the analyzed patients the mean IOP decrease was 9.3 mmHg (maximum decrease of 14 mmHg and minimun of 5 mmHg). While average pre-surgical IOP was 27.3 mmHg (range 25-31 mmHg), average post-surgical IOP was found to be 16 mmHg (range 10-20 mmHg). The need for hypotensive topical medications decreased in all cases: in 3 of them were no longer necessary, 1 continued treatment with brinzolamide and 2 others with a fixed combination. None of the cases experienced intraoperative complications or a decrease  in the endothelial cell counting.

In our experience, iStent-W implantation in OHT or glaucoma secondary to corneal transplantation is a safe and effective technique for controlling IOP and reducing the hypotensive drugs used in this type of patients.