الفهرس 
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Abstract
Retinopathy of prematurity is a disorder of retinal vascular development in preterm infants. It remains a major cause of childhood blindness worldwide despite advances in neonatal care.
Because VEGF is highly elevated in advanced ROP and has been found to play a central role as the driving force for neovascularization, blocking VEGF with anti-VEGF agents seems to be a reasonable approach.
Bevacizumab injection neutralizes the VEGF already present in the vitreous cavity, but it does not inhibit continued production of VEGF in the avascular area. Laser treatment in the avascular retina further decreased VEGF production by destroying VEGF expression in the avascular retina. In addition, VEGF is not the only growth factor up-regulated in the eye. Insulin-like growth factor-1 and other growth factors may also play some role in the pathogenesis of ROP. Inhibition of VEGF by bevacizumab may not be able to induce regression in all ROP cases. However, the majority of eyes responded well to this treatment. Because the effects of bevacizumab injection in ROP eyes remain to be fully elucidated, standard laser treatment could serve as a backup in those cases that are nonresponsive.
This study found that the addition of intravitreal bevacizumab (IVB) (0.625 mg) to conventional laser photocogulation in stage 3 ROP (zones I and II) resulted in faster resolution of plus disease, more complete resolution of neovascularization, and less need for secondary intervention, without exaggeration of the cicatricial response. When IVB was added to supplemental laser treatment, the cicatricial response was more intense than cases where IVB was added to the primary laser treatment, but without the occurrence of retinal detachment. Thus IVB may be useful as an adjunct to primary laser treatment. The late addition of IVB to supplemental laser treatment requires further study.
This study found that combined intravitreal bevacizumab and laser photocoagulation treatment promptly and strikingly halted the progression of vascular proliferation. Although new vessel regression and the disappearance of plus disease may be achieved by laser photocoagulation alone, the prompt resolution of vascular engorgement and tortuosity from as early as postoperative day 1 suggests a possible adjunct effect of intravitreal bevacizumab.
Therefore, bevacizumab treatment seems to be better than laser treatment especially for zone 1 ROP. However, this study is only a small case series report, and no definite conclusions can be drawn. The other potential benefits of anti-VEGF therapy in comparison with ablative treatment include the ease of the procedure, the reduced operating time, and no need for equipment related to laser or cryotherapy. Bevacizumab is also less destructive to the retina. Furthermore, tunica vasculosa lentis regression and pupil dilation facilitate further follow-up or subsequent treatments. Finally, the technique eliminates complications associated with ablative treatments, such as refractive errors or visual field loss. However, long-term study is needed to substantiate this result.
Ocular complications did not occur, and no apparent systemic adverse effects related to the injection were found up to the date of the last follow-up.
These results are encouraging because they suggest the potential of a new treatment for ROP.