Purpose: To report the outcome of intravitreal 0.312 mg bevacizumab (IVB) monotherapy in acute retinopathy of prematurity (ROP) and to describe the vascular development over time.
Methods: Seventeen prematurely born infants were treated with IVB (0.312 mg in 0.025 mL per eye) because of acute ROP in posterior Zone II or Zone I, including aggressive posterior ROP. Infants were examined by fluorescein angiography (FA) using RetCam II or III (Clarity Medical Systems Inc) before IVB (n = 21 eyes), within 6 weeks (n = 23 eyes), 8 to 13 weeks (n = 22 eyes), and up to 45 months (n = 10 eyes).
Results: Acute ROP regressed in 19 out of 27 analyzed eyes (70%), including 100% and 80% of posterior Zone II and Zone I eyes, respectively, but only 25% of aggressive posterior ROP eyes. Early recurrences (11%, all aggressive posterior ROP) and late reactivations (18%) were observed within 1 week and at 9 to 12 weeks, respectively. All eyes showed leakage at the junction of the vascularized zone and capillary malformation on FA before treatment. Vessel branching abnormalities and circumferential vessel formation were typical FA features after treatment. Vascular outgrowth after one IVB became complete in 87.5% of eyes for which FA was available up to at least 9 weeks after IVB.
Conclusion: A single dose of 0.312 mg bevacizumab was efficient to induce regression of ROP in posterior Zone II and most of Zone I cases, but not in aggressive posterior ROP. FA describes vascular abnormalities, the importance of which warrants further investigation.