The innermost layer of the eyeball wall is the retina, the light-sensitive layer where we see objects. Newborns born at full term are usually born 38 weeks after the mother’s pregnancy, when the various structures in the eye are largely developed. This is not the case for premature babies, whose retinal vessels are prone to lesions, i.e., abnormal proliferation in the vitreous. On the one hand, this abnormal structure prevents light from reaching the retina, affecting the transparency of the vitreous; on the other hand, the proliferating tissue pulls on the retina, causing detachment of the retina and leading to blindness in the child. This disease occurs in premature infants, low birth weight infants, and newborns with a history of oxygen absorption, and it is one of the most important causes of neonatal blindness. Oxygen inhalation is also a risk factor. Oxygen must be used in order to save the life of a premature baby. Oxygen itself is not toxic, it is mainly an overreaction of the newborn’s body to high concentrations of oxygen. The newborn’s body is not well developed, and when there is hypoxia or low oxygen, the retinal blood vessels will grow in all directions like vines. When sufficient oxygen is given to the outside world, the blood vessels are “lazy” to grow. Once oxygen is stopped, the retinal blood vessels will overgrow, leading to retinal proliferative disease and blindness. Screening for retinopathy of prematurity (less than 36 weeks of gestation) or low birth weight (less than 2,000 grams of birth weight) is required for all premature infants. Screening time is: if the birth gestational week is greater than 32 weeks, the first screening after birth; if the birth gestational week is less than 32 weeks, to correct the gestational age of 32 weeks (corrected gestational age = gestational week + weeks after birth) that the first screening. The time of re-screening should be based on the results of the first examination. If the local hospital is not equipped for screening, parents should bring their baby to the vitreoretinal center of Tianjin Eye Hospital early to see the chief specialist, Prof. Chen Song, for examination. Wang Jinxing, Ophthalmology Department, General Hospital of Ningxia Medical University
What measures should be taken to prevent blindness due to retinopathy of prematurity?
First, control the duration of oxygen use and try to use it for a short period of time.
Second, the fundus should be checked regularly for premature or low weight infants with oxygen use and followed up to 3-6 months.
Third, laser and cryotherapy can be chosen for progressive lesions, and most of them can be regressed.
Fourth, vitreous or retinal surgery can be chosen for advanced cases, but the results are poor.
If retinopathy is detected early in premature infants, the treatment will be very good, basically, through laser or surgical treatment, the child’s vision can be completely unaffected. He told the reporter that they previously followed many premature babies and in the clinic, the high incidence of lesions is in premature babies growing to 37 and 38 weeks. However, for some preterm babies, the time after 38 weeks cannot be neglected. There was a newborn among Yongqiang Xiong’s patients who did not show symptoms of lesions until after 44 weeks, and this child’s eyes were not affected because they were treated in the first place. Reducing blindness caused by retinopathy of prematurity is important for regular follow-up and early detection and treatment, and many lesions can be cured. However, once the best time for treatment is missed and the disease reaches an advanced stage, the child loses the opportunity for surgery and may end up with loss of vision and atrophy of the eye, leaving lifelong regrets.
The disease can be divided into five stages according to the severity of retinal lesions. In the first and second stages, the retina is somewhat abnormal compared to the normal neonatal retina, but at this time there are no obvious neovascularization and no treatment is needed. Most neonates will heal spontaneously, but regular checkups are required because some neonates will continue to progress to the third stage. In the third stage, neovascularization begins to appear in the retina, which can be treated by condensation or retinal photocoagulation, and the condition of most children can be controlled and improved. However, if left untreated, the neovascularization continues to proliferate, pulling the retina and causing local retinal detachment and eventually total retinal detachment, which is the fourth and fifth stage of change. If a child has total retinal detachment in both eyes, there is little hope of cure.