Upon assessing the effect of intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) agents on immediate and long-term intraocular pressure (IOP) elevation and glaucoma, researchers found that these injections can cause an immediate and transient as well as a long-term increase in IOP. They note that there is insufficient data to determine at-risk populations, the impact of these injections on glaucoma progression and the significance of several intervention techniques used to reduce IOP.

Of the 34 evaluated studies, those reporting on short-term IOP elevation (between zero and 60 minutes) showed that an immediate increase in IOP can be seen in all patients when measured between zero and 30 minutes of intravitreal injection and that IOP elevation decreases over time. The results of those studying long-term IOP elevation were mixed; seven studies reported that between 4% and 15% of patients developed a sustained IOP elevation from nine to 24 months after injection; whereas, six studies found no long-term change in IOP from one to 36 months after injection. 

The team found that pretreatment with glaucoma medications, anterior chamber tap, vitreous reflux, longer intervals between injections and longer axial lengths were associated with lower IOP elevations after injection. They note that data was mixed on the relationship between IOP rise and the type of intravitreal injection, number of intravitreal injections, pre-existing glaucoma and globe decompression before injection. They add that there were no data on the onset or progression of glaucoma in the studies reviewed.