Poor intraoperative visibility and postoperative astigmatism associated with trabecular micro-bypass stent for corneal dystrophy: A case report

There are reports of safe cataract surgery in eyes with posterior polymorphous corneal dystrophy (PPCD); however, to our knowledge, there are no reports of minimally invasive glaucoma surgery (MIGS) in eyes with PPCD. Herein, we report a case of poor intraoperative visibility with gonioscopy, postoperative corneal edema, and corneal astigmatism in eyes with PPCD treated with trabecular micro-bypass stent combined with cataract surgery. A 78-year-old man was referred to our hospital for MIGS. He presented with bilateral corneal endothelial vesicular changes and band lesions. Endothelial cell density was 2983/2871 cells/mm2 (right/left eye), central corneal thickness was 581 μm/572 μm, best-corrected visual acuity values (Snellen equivalent) were 20/32 (right) and 20/100 (left), and corneal astigmatism was -2.7D in the right eye and -2.5D in the left eye. After phacoemulsification and aspiration with intraocular lens implantation with a 2.4-mm corneal incision in both eyes, trabecular micro-bypass stents were inserted successfully despite the poor intraoperative visibility with gonioscopy. One week after surgery, the central corneal thickness was 614 μm/609 μm, and Descemet's membrane folds and mild corneal edema were observed. Best-corrected decimal visual acuity was 20/40 for the right eye and 20/50 for the left eye. In the left eye, total corneal astigmatism increased from -2.5D to -5.5D. Corneal astigmatism and edema showed gradual improvement. Although reports have shown that cataract surgery can be safely performed in eyes with PPCD, MIGS in eyes with PPCD may require caution regarding intraoperative visibility with gonioscopy and visual function in the early postoperative period.