Dynamic angle closure following pars plana vitrectomy with perfluoropropane gas

To report the clinical course of an aphakic patient who developed positional secondary angle closure glaucoma following pars plana vitrectomy (PPV) with perfluoropropane (C3F8) gas tamponade. A 23-year-old male presented due to a two-year history of vision loss in the left eye. Best-corrected visual acuity (BCVA) was 20/200 and intraocular pressure (IOP) was 12 mm Hg OS. Exam revealed iridodonesis and aphakia of both eyes, and a total RRD in the left eye. The patient underwent scleral buckle plus PPV with 15 % C3F8 gas and was instructed to maintain face-down positioning for 5 days. On post-operative day 1, IOP was 32 mm Hg and exam revealed significant diffuse corneal edema, a large epithelial defect, and 85 % C3F8 fill of the vitreous cavity. Patient was started on IOP-lowering drops but continued to have elevated IOP and corneal epithelial sloughing over the next 3 weeks. He was taken for a superficial keratectomy, but when placed supine under the microscope, a large new gas bubble was visualized overlying the pupil in a now shallow anterior chamber (AC) and IOP was 52 mm Hg. The patient was positioned back upright and the gas bubble migrated posteriorly out of the AC with return of IOP to 25 mm Hg. The dynamic nature of his IOP raised concerns for intermittent angle closure by C3F8 induced by supine positioning. Thus, a pars plana aspiration of the C3F8 gas was performed and resulted in normalization of the IOP. Dynamic, positional secondary angle closure glaucoma can occur after vitrectomy with C3F8 in the setting of aphakia. This is the first report to capture C3F8 gas migration causing intermittent acute angle closure in real-time. Due to its intermittent nature however, the diagnosis may not be initially apparent at the slit lamp. Thus, we suggest this potential complication should be carefully monitored for and discussed when advising post-vitrectomy positioning in aphakic patients.