Evaluation of intraocular pressure change and anterior segment parameters after intravitreal bevacizumab injection – Cannula size matters

Abstract

PURPOSE: To determine the changes in intraocular pressure (IOP) and anterior chamber parameters following intravitreal bevacizumab injection with different sizes of cannulas. METHODS: This clinical trial was conducted with 70 eyes of 70 patients who received an intravitreal injection of bevacizumab with 26 G (Group 1) or 30 G (Group 2) needle. Preinjection and postinjection 30 th -min IOP and pentacam measurements were obtained. Anterior chamber depth (ACD), anterior chamber volume (ACV), central corneal thickness (CCT), corneal volume (CV), and iridocorneal angle (ICA) measurements were evaluated in pentacam. RESULTS: Preinjection mean IOP values in Group 1 and 2 were 14.7 ± 3.29 mm Hg and 15.1 ± 2.87 mm Hg, respectively. Postinjection mean IOP in Group 1 was 16.8 ± 6.24 mm Hg and in Group 2 was 20.3 ± 3.66 mm Hg. Postinjection mean IOP values were significantly higher than preinjection values in both groups (Group 1 P < 0.005 and Group 2 P < 0.001). IOP change was significantly higher in Group 2 after injection ( P < 0.05). In both groups, the change in IOP found to be more significant in phakic eyes than pseudophakic eyes (Group 1 P < 0.001, Group 2 P < 0.001). CCT and CV were significantly higher in both groups 30 min after the injection than preinjection (Group 1 and Group 2; P < 0.01). In Group 2 ACD, ACV and ICA values were significantly lower than preinjection values ( P < 0.05). CONCLUSION: Needle bore size is an important parameter that influences anterior segment parameters and IOP change in the intravitreal injection. IOP rise and anterior segment changes are more prominent with a thinner cannula.

Effects of repeated intravitreal bevacizumab administration on anterior segment parameters and limbal stem cells

“…Consistent with the current results, a retrospective study of 100 patients by Arslan et al demonstrated a significant decrease in ACD at 1 and 2 months after injection compared to that of the pre-injection phase [14]. Additionally, in a study of 70 patients by Hamidi et al, ACD after injections was significantly decreased compared to that of the pretreatment phase [13]. In contrast, in a study by Guler et al measuring the ACD 1 month after bevacizumab injection, the mean value decreased in the eyes of 43 people 1 month after injection, although the difference was not statistically significant [44].…”

“…Although there have been numerous studies on the effect of intravitreal injections on the ocular structures, especially the posterior segment, assessment of changes in the anterior segment has been limited [13,14]. Most investigations have benefited from new imaging techniques, particularly optical coherence tomography (OCT) [15].…”

Immediate Effect of Intravitreal Bevacizumab Injection on Intraocular Pressure

“…15,16 Association of needle size with acute IOP rise after intravitreal injections showed that IOP rise was more with thinner needles which was most likely because of no or less conjunctival vitreous reflux with these needles. 17,18 Gomez-Mariscal M. et al, conducted a study to evaluate the effect of intravitreal anti-VEGF injections on IOP and optic nerve head. They evaluated the acute and chronic changes in these parameters.…”