Sustained IOP Spikes May Follow Anti-VEGF Injections in Patients With Glaucoma

Sustained intraocular pressure (IOP) spikes are a potential complication of retinal treatments with intravitreal injections for patients who also have either glaucoma or high IOP, according to research published in Clinical Ophthalmology. The study shows specific clinical factors that contribute to larger and longer IOP rise when using a 31-gauge needle to treat patients with prior glaucoma or pretreatment pressure higher than 25 mm Hg.

Researchers evaluated 617 consecutive eligible adult patients at several clinics in the US who underwent intravitreal injections with bevacizumab or ranibizumab to treat macular edema triggered by age-related macular degeneration (AMD; n=355), diabetic retinopathy (DR; n=199), or retinal vein occlusion (RVO; n=63). Physicians used a hand-held tonometer to measure patients’ IOPs before injection, and every 10 minutes afterwards for 50 minutes. Patients with sustained IOP spikes higher than 35 mm Hg at 30 minutes received intervention of anterior chamber paracentesis (ACP).

A mean baseline IOP of 16±4 mm Hg in the nonintervention group increased to 25±9 mm Hg after 10 minutes. Of the 617 participants, 98% resolved to pretreatment pressure level by 50 minutes. Individuals who experienced sustained IOP spikes and required ACP (n=17) presented with a mean pretreatment IOP of 24±7, which rose to 47±10 mm Hg, a significant intergroup 10-minute postinjection difference (P <.0001).

Of those who received ACP, 82.3% had a prior glaucoma diagnosis vs 14.2% for those who did not require intervention (P <.0001).

The researchers concluded that patients with baseline pressures higher than 25 mm Hg and a history of glaucoma are likely to require ACP approximately 58.3% of the time. Moreover, data shows that anti-VEGF treatments conducted using a 31-gauge needle are significantly more likely to result in a sustained IOP spikes than those conducted using a 30-gauge injection (P <.0001).

“The use of smaller gauge needles and less vitreous reflux was also associated with a greater increase in post-injection IOP,” according to researchers. “As a result, we recommend that clinicians should, at the minimum, consider close observation of IOP after IVI in patients with high pre-injection IOP and glaucoma.”

Previous studies have shown greater incidence of new glaucoma diagnoses, as well as starting IOP-lowering medication or having glaucoma surgery in patients undergoing more frequent injections per year compared with those needing fewer treatments.

A population sample from one geographical region may limit generalizability. Strengths comprise a prospective design and examination of specific factors impacting immediate post-injection IOP.