Slit-Lamp Management of Silicone Oil-Induced Pupillary Block After Vitrectomy

Silicone oil (SO) is commonly used as a tamponade agent in vitreoretinal surgery for complex retinal detachments, but its migration into the anterior chamber (AC) can cause pupillary block and secondary angle-closure glaucoma (ACG). We report a 51-year-old Japanese man with proliferative diabetic retinopathy who underwent combined phacoemulsification and pars plana vitrectomy with SO tamponade for tractional retinal detachment. On postoperative day 1, SO was observed in the AC with normal intraocular pressure (IOP) and anterior chamber depth; however, on day 2, he developed pupillary block with a flattened AC and IOP of 60 mmHg. At the slit lamp, a dispersive ophthalmic viscosurgical device was injected through a corneal side port, and the iris was depressed posteriorly with a blunt cannula, allowing aqueous humor to re-enter the AC. A transcorneal peripheral iridotomy was then performed with a microvitreoretinal blade, resulting in the resolution of the pupillary block and normalization of IOP. This case highlights a practical outpatient technique that enables an effective management of SO-induced pupillary block at the slit lamp, avoiding the risks of supine surgical intervention or premature SO removal and preserving the tamponade effect.