Intravitreal injection of bevacizumab: changes in intraocular pressure related to ocular axial length.

Purpose: To evaluate the immediate and short-term effects of intravitreal injection of 1.25 mg/0.05 ml of bevacizumab on intraocular pressure related to different ocular axial lengths.

Design: A prospective case series of consecutive patients referred to the Department of Ophthalmology, San Pietro-Fatebenefratelli Hospital, from September 2011 through January 2011.

Methods: Twenty-five patients (10 men and 15 women, mean age 70.2 ± 8.98 years) scheduled for intravitreal injection of bevacizumab for the treatment of neovascular age-related macular degeneration were enrolled in this study. Axial length was measured preoperatively using IOLMaster. Intraocular pressure was measured before injection, after 1 min and after 15 min using Tono-Pen XL tonometry.

Results: The mean intraocular pressure change following the intravitreal bevacizumab injection was 21.92 ± 6.95 mmHg after 1 min and 6.24 ± 3.77 mmHg after 15 min. The mean axial length of the examined eyes was 23.2 ± 1.06 mm. A good correlation was observed between the axial length and intraocular pressure rise after both 1 (R (2) = 0.752, p < 0.001) and 15 min (R (2) = 0.559, p < 0.001).

Conclusions: Patients undergoing intravitreal injection of 0.05 ml of bevacizumab can be exposed to intraocular pressure increases correlated to ocular axial length.