Intraocular Pressure Variations After Intravitreal Injections Measured With an Implanted Suprachoroidal Telemetry Sensor

Abstract

Purpose: Intravitreal injections (IVIs) may create transient intraocular pressure (IOP) elevation. This report describes continuous IOP fluctuations following multiple IVI measured with a permanent implantable sensor. Patients and Methods: We report the case of a 49-year-old white glaucomatous male with refractory macular edema secondary to central retinal vein occlusion in his left eye who underwent deep sclerectomy combined with the implantation of a suprachoroidal tonometry sensor. Serial IOP measurements were performed immediately before and after each IVI over a 1-year period. Results: During the first 7 months following deep sclerectomy, IOP remained below 10\u2009mm\u2009Hg. During this period, mean IOP before each injection was 2.1±2.6\u2009mm\u2009Hg, and each IVI caused a reduction of 1.2±0.8\u2009mm\u2009Hg on average, with a maximum reduction of 2.7\u2009mm\u2009Hg, before IOP normalized within 50 minutes to 24 hours. From 7 months postoperatively, mean IOP increased to the low teens. During this period, mean IOP before each injection was 9.9±1.8\u2009mm\u2009Hg, and each IVI caused an increase of 15.8±11.7\u2009mm\u2009Hg on average, with a maximum increase of 44.8\u2009mm\u2009Hg, before IOP normalized within 20 minutes to 4 hours. Conclusions: During the initial postoperative phase, IVI may cause acute reduction in IOP, either through subconjunctival leaks or increased filtration secondary to increased fluid pressure. Several months after surgery, this effect subsides and IOP spikes sharply immediately after each IVI, suggesting the resolution of the initial mechanism, most likely through scarring and fibrosis.