Retinopathy of Prematurity, or ROP, is a condition affecting premature infants. This happens when abnormal blood vessels start growing and spreading across the retina, which can cause retinal detachment, resulting in permanent blindness.
It is one of the leading causes of vision impairment in children, and the consequences can last a lifetime. The good news is that recent research and advances in the diagnosis and treatment of ROP means better outcomes for children who are affected by this disorder.
One of these treatments is known as “anti-VEGF” therapy. The initials stand for “Vascular Endothelial Growth Factor.” This is a protein that causes the growth of blood vessels, which are produced by cells in the retina. Before explaining how this therapy works, however, it may be helpful to understand exactly what ROP is and how it occurs.
During fetal development, blood vessels of the eye grow from the middle of the retina and spread outward. This growth continues right up until about three weeks before delivery. When an infant is born prematurely, this process has not been completed. In most cases, the blood vessels continue to grow normally; however, when this does not happen, ROP can be a result.
Abnormal blood vessels start growing outward from the retina, causing bleeding inside the eyes. As the blood and vessels are reabsorbed, membranes develop, putting pressure on the retina and causing retinal detachment. In general, infants most likely to develop ROP are those born at 31 weeks or earlier. Premature infants who suffer from any respiratory distress, infections, hemorrhaging or other perinatal disorders should be screened for ROP.
Anti-VEGF therapy involves using medications in order to inhibit the growth of abnormal retinal blood vessels. It has been used for some time in treating age-related macular degeneration as well as some cancerous tumors. Medications typically used include Avastin (becacizumab), Lucentis (ranibizumab) and tyrosine kinase inhibitors such as Votrient (pazopanib).
There is another issue involved in ROP – and that is the availability of physicians who have expertise in the prevention and treatment of ROP. When under the care of a specialist or obstetrician with experience and training in dealing with ROP, over 90% of at-risk infants have better outcomes, even with severe cases.
However, at health care facilities that are poorly staffed and equipped with fewer resources, such infants are more likely to experience permanent blindness. The good news is that technological advances such as wide-angle retinal imaging, combined with information technology, is enabling physicians to consult with colleagues with more experience in dealing with cases of ROP anywhere in the country.
Ophthalmologist Michael Chiang M.D. of the Oregon Health & Science University in Portland notes that:
“ROP care is now being gradually transformed by some of these technologies. By evaluating other emerging imaging technologies, understanding their benefits and limitations, and gradually implementing them into practice when warranted, pediatric ophthalmologists will be able to enhance the care they provide to patients for a broader range of problems in the future.”
Dr. William V. Good of San Francisco's Smith-Kettlewell Eye Research Institute acknowledges that major progress is being made. While there is much work that needs to be done, he says, “It's time to consider the real possibility that this condition can be eliminated. When that happens, we will have achieved nothing short of a miracle.”