Changes in the Plasma Levels of VEGF, IGF-1 and Growth Parameters in Infants with Retinopathy of Prematurity after Intravitreal Injection of Bevacizumab and Laser Therapy

Purpose: To determine the changes in serum levels of free vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) in infants with retinopathy of prematurity (ROP) who received intravitreal injection of bevacizumab (IVB) or laser therapy; and to assess the changes in main growth parameters of infants. Methods: A prospective case series study including 38 eyes from 19 infants with type 1 ROP was conducted. Ten patients received simultaneous bilateral IVB at 0.625 mg per eye, and nine patients were treated with conventional laser. Using the enzyme-linked immunosorbent assay (ELISA), serum levels of VEGF and IGF-1 were measured before, 1 month, and 2 months after treatment. Growth parameters including weight, length, and head circumference and their Fenton’s Z-score were also measured. Results: Serum VEGF levels were suppressed significantly, 1 month after IVB (P=0.006); but the reduction was not significant in the laser group (P=0.066). Serum levels of VEGF increased significantly between 1 and 2 months after IVB (P=0.017). Significant increase was observed in the serum levels of IGF-1 after 2 months in laser group (P=0.008) in contrast to IVB (P=0.059). Z-scores of all growth parameters decreased in the first and second months that were significant in the IVB group except weight z-score. A positive correlation was found between the serum levels of IGF-1 and weight, length and head circumference in both IVB and laser group. Conclusion: Serum VEGF levels showed a transient reduction after IVB which lasted less than 2 months. Growth velocity of length and head circumference was significantly decreased after both IVB and laser, although a greater decrement was detected in the IVB group