Purpose: To evaluate possible changes in anterior scleral thickness and structure and changes in the anterior segment in eyes receiving multiple intravitreal injections using ultrasound biomicroscopy imaging.
Methods: Prospective, interventional, nonrandomized, cross-sectional study. Both eyes from 33 patients previously treated at least by 15 intravitreal injections in one eye only for retinal diseases were included. Intravitreal injections were performed by ophthalmologists using an aseptic standardized procedure. Ultrasound biomicroscopy examination was performed in all eyes, and scleral thickness was measured at the pars plana in four quadrants. Anterior chamber depth and ciliary body size were measured. Scleral thickness in the study eye was compared with the fellow eye. Secondary outcome measures were 1) anterior chamber depth; 2) ciliary body size; 3) scleral qualitative changes in the study eye compared with the fellow eye and 4) risk factors for scleral thinning.
Results: There was no statistically significant difference in scleral thickness between the study and fellow eyes when comparing each quadrant between the two eyes (P = 0.86 superotemporal; P = 0.76 superonasal; P = 0.72 inferonasal; P = 0.55 inferotemporal). Scleral thickness was neither related to the number of injections nor to the duration of treatment in the treated eye.
Conclusion: Multiple intravitreal injections do not impact scleral thickness in a clinical practice using different injection sites.