Being a mother who has had preemies myself, I understand all of the added risks that babies born early undertake. One of the conditions which preemies are sometimes at risk for is called Retinopathy of Prematurity or “ROP” for short. “Retinopathy of prematurity (ROP) is a potentially blinding eye disorder that primarily affects premature infants weighing about 2¾ pounds or less that are born before 31 weeks of gestation (A full-term pregnancy has a gestation of 38–42 weeks) (source 1). The smaller a baby is at birth, the more likely that baby is to develop ROP. This disorder—which usually develops in both eyes—is one of the most common causes of visual loss in childhood, sometimes leading to lifelong vision impairment and blindness. “(source 1)
Other factors and conditions besides low birth weight and gestation can also contribute to the risk of an infant developing ROP, these include:
- blood transfusions
- respiratory distress
- breathing difficulties
- brief stop in breathing (apnea)
- heart disease
- high CO2 levels in the blood
- low blood acidity (pH)
- low blood oxygen
- bradycardia (slow heart rate)
- the overall health of the infant
So what exactly is ROP? The exact mechanism of how ROP occurs is still not clear. What we do know is, from about the fourth month of pregnancy until birth, intricate networks of blood vessels are developing inside each eye. The blood vessels grow through the optic nerve and start to branch out to deliver vital blood (and oxygen) to the inner eye and peripheral retina. In preemies, these blood vessels grow abnormally or sometimes stop growing in the eye too early. This incomplete vascularization prevents the far outskirts of the retina from getting the oxygen it needs for proper development (stages 1 and 2 of ROP). In some severe cases, new blood vessel growth can occur after these primary blood vessels have stopped their growth (stage 3 of ROP). The new blood vessels think they are coming to the rescue to deliver blood and oxygen where the original blood vessels failed. However, the new blood vessels are weak and fragile, they can start to leak blood into the eye which causes scarring and tension on the retina. If this scarring pulls and tugs the retina too far, it can detach (stage 4 is a partial retinal detachment, stage 5 is a total retinal detachment). A retinal detachment can lead to permanent vision loss and is an emergency situation which calls for prompt examination and immediate medical treatment.
To understand how severe an individual is afflicted with ROP, we classify the condition into stages 1 to 5(with 5 being most severe), zones 1-3 ( with 1 being the central retina, and therefore the least desirable area affected since it is crucial to someone’s quality of vision in their everyday life) and blood vessel appearance (twisting and dilating of the new blood vessels at the demarcation line/ridge, also known as ‘Plus Disease’). (source 3).
Prognosis for the mild stages of ROP is very good and in many cases, does not significantly impact the infant’s vision in the long run. However 1 in 10 premature infants with ROP will progress through stage 3 and into the most severe stages 4 and 5 which carry the risk of lifelong blindness. (source 4) Early detection is absolutely necessary and essential to properly classify the sight-threatening condition and decide on a treatment plan. Treatments are available to help slow the growth of new leaky blood vessels in stage 3 and retinal surgery can also be performed in later stages to help preserve vision but again, eye examinations are crucial at birth, while the babies are in the NICU and beyond.
Babies born with a birth weight of 2¾ pounds or less or those who are born before 31 weeks of gestation should have retinal exams. The first eye exam should be within 4 to 9 weeks of birth. Follow up retinal exams will be scheduled based upon the findings at the first exam. Parents should know their child’s needed follow up schedule before they leave the NICU. (source 4).
With new statistics indicating that the rate of premature births in America has increased by 36 percent in the past 25 years (source 5), more babies are at risk for vision loss now than ever before. Please support the March of Dimes in their mission to help all babies get a healthy start through research, education and raised awareness of prematurity.
Picture the most beautiful sunset you have ever seen, the vibrant petals of a rose or the smiles on your loved ones faces. Protect your vision and help others also see the light. November is Prematurity Awareness Month. Please Donate to the March of Dimes here. Thank You!