Posterior vitreous detachment following intravitreal drug injection

BACKGROUND: To evaluate the incidence of posterior vitreous detachment (PVD) induced by intravitreal injection of different intravitreal drugs. METHODS: This prospective observational study included 61 patients (61 eyes) with different underlying retinal diseases: exudative age-related macular degeneration (n = 47), cystoid macular edema (CME) after retinal vein occlusion (n = 8), and CME of other origin (n = 6). Bevazicumab (1.25 mg) was injected into 25 eyes, ranibizumab (0.5 mg) into 27 eyes, triamcinolone (4 mg) into six eyes, and a combination of bevacizumab and triamcinolone into three eyes. Patients with initial PVD were excluded. Patients were followed for at least 4–6 weeks after their last injection by Fourier-domain OCT, fundus biomicroscopy and ultrasound B-examination. RESULTS: Overall, 15 of 61 eyes developed a PVD after intravitreal injection (n = 6 after ranibizumab, n = 7 after bevacizumab and n = 2 after triamcinolon) within a mean follow-up period of 11.1 weeks. PVD occurred in three eyes after the first injection, in three eyes after the second, and in seven eyes after the third injection. Incidence of PVD correlated with increasing age. CONCLUSION: Intravitreal injection of commonly-used drugs seems to induce posterior vitreous detachment, which may thus influence the outcome of the underlying disease.