Surgically Induced Corneal Astigmatism Following Intravitreal Ranibizumab Injection

To evaluate surgically induced astigmatism (SIA) after an intravitreal ranibizumab (IVR) injection.

Fifty eight eyes of 58 patients who underwent IVR injection due to age-related macular degeneration (wet form) or macular edema were included in this study. Patients’ pre- and postoperative detailed ophthalmologic examinations were done and topographic keratometric values (K1, K2) were noted. Pre- and postoperative measurements were compared.

The mean preoperative astigmatism of 0.87 Diopters (D) was found to be 0.95 D, 0.75 D, 0.82 D and 0.78 D on the 1st day, 3rd day, 1st week and 1st month, respectively. After injection, absolute change in astigmatism was found to be 0.08 D, 0.12 D, 0.05 D and 0.09 D on the 1st day, 3rd day, 1st week and 1st month, respectively. The absolute change in astigmatism seemed to be insignificant in terms of refractive analysis, however; when we performed a vectorial analysis, which takes into account changes in the axis of astigmatism, the mean value of induced astigmatism were found to be 0.33±0.22 D, 0.32±0.29 D, 0.41±0.37 D, 0.46±0.32 D on the 1st day, 3rd day, 1st week and on 1st month, respectively.

Intravitreal injection is a minimally invasive ophthalmologic procedure, however; it may still cause statistically significant induced astigmatism when evaluated from a vectorial point of view.