Retinopathy of premature infants
Synonyms in the broadest sense
Premature retinopathy
English: Terry's syndrome, retinopathy of prematurity
introduction
Premature babies are, by definition, children born before the 37th week of pregnancy. However, premature retinopathy is more common in children born before the 33rd week 1500g birth weight have or suffer from severe general illnesses and have a prolonged need for oxygen.
Depending on the characteristics, the Retinopathy of premature infants for blindness to lead. However, thanks to intensive research into the right therapy at the right time, the risk of going blind has significantly decreased. However, to this day it is the third most common cause of blindness in children.
definition
Retinopathy of premature infants is an underdevelopment of the Retina of the eye at Premature babies. Since the newborn saw the light of day too early, its organs are not yet fully developed and prepared for the world outside the womb.
It is a threatening one Disease to the eyewhich can lead to blindness in premature babies. The vessels of the eyes are not yet developed sufficiently and are therefore damaged.
causes
General causes
Retinopathy in a Premature birth is caused primarily by the toxicity of oxygen on the developing vessels of the retina. Oxygen acts as a poison in premature births because their retinal vessels have not yet adapted to the changed environmental conditions. In the womb, the vessels would have developed even further, around the entire body Retina to supply. If the oxygen concentration rises too early, vascular growth stops. Oxygen prevents the release of growth factors that are supposed to stimulate the retinal vessels to grow.
Full term babies usually have no risk of developing retinopathy, as their retina is already completely supplied with blood vessels.
Risk factors
Other risk factors that can promote retinopathy are:
- immaturity
- Birth weight less than 1000g
- Increase in CO2
- Blood transfusions
What exactly happens when retinopathy occurs in premature babies?
The exact event has not yet been clearly clarified and is still being discussed. The following theory provides an explanation:
Once the premature baby is born and begins to breathe on its own - although some premature babies are also artificially ventilated - the proportion of oxygen in theirs increases blood. This fact causes the vessels of the immature retina to contract. Thus, the retina is not only equipped with immature vessels, but cannot be adequately supplied with oxygen, growth factors and nutrients through these existing vessels. If this narrowing is permanent, the vessels close completely.
Based on various findings on the fundus, the Retinopathy of premature infants be divided into five stages, each of which is characterized by specific, progressive characteristics. They are all characterized by an increase in the vascular connective tissue located outside the retina. This connective tissue forms strands on the basis of which the normal, vascular (vascularized) Retina can be distinguished from the avascular retina. In some cases, growth factors are increasingly released in the stadiums. In the case of mild courses, this process is limited to the area around the retina. In more severe cases, the newly formed vessels grow into the vitreous humor, among other things, and can certainly cause retinal detachment. Retinal detachment leads to blindness if not corrected.
Another complication is the displacement of the lens forward. The outflow of aqueous humor is obstructed and it comes to glaucoma (green Star: increased Intraocular pressure with various causes).
stage
- Boundary line that separates the normal retina from the immature retina
- The borderline is raised like a wall
- New abnormal blood vessels form, connective tissue multiplies, and both grow into the vitreous humor
- Partial detachment of the retina due to the tension exerted by the attached vessels and strands of tissue
- Complete detachment of the retina
Furthermore, a genetic component is considered, because African-Americans develop retinopathy prematurely less often than Caucasians.
course
Usually both eyes are affected. However, the two eyes can develop different degrees of severity.
The course of the disease is variable: the first changes in the retina can be noticed after 3 weeks. The maximum of the changes, however, is around the calculated due date.
forecast
If there is no blindness due to retinal detachment or if it is mild, long-term effects can still be observed. Strabismus, weak and nearsightedness, and glaucoma are described. Delayed retinal detachment can occur years after retinopathy. This complication is much feared because it is associated with blindness. However, it is not very common. In rare cases, these changes regress spontaneously.
Therapies such as blocking receptors for growth factors are still a long way off, as they would also stop the growth of the rest of the organs.
diagnosis
The diagnosis is made by the Ophthalmologist, which routinely examines all premature babies on a regular basis. Equipped with a lamp and a magnifying glass, he can look the little one in the eye. What may look cruel to outsiders is, however, of the utmost importance: the so-called eyelid lockers. The eyes are kept open by means of these metal brackets. The pupils were dilated with medication (eye drops) in order to get an optimal view. The table above describes which findings the ophthalmologist sees in the various stages. Of course, an inconspicuous fundus is desirable.
An initial examination in the 6th week of life has proven to be sufficient, since the retinal damage that begins earlier is a rarity.
therapy
It should be noted in advance that the premature baby itself needs special care. In larger clinics there are special wards for premature babies where the little ones receive medical and nursing care. As a rule, there is also an ophthalmologist in-house who takes care of the retinopathy of premature babies on site. In order to care for a premature baby efficiently, several medical disciplines need to work together.
Mild forms can regress without permanent damage, such as blindness. If the form is severe, it can progress through Laser therapy to get stopped. Also Cryotherapy (Exposure to cold) is used here. Vessels which are in the Vitreous ingrowth can be deserted and thus stopped in their growth.
Once the retina has been detached, Cerclagen is used. They press the retina back against the original surface and promote regrowth.
For a while the Administration of vitamin E. as a precautionary measure for discussion. In studies, however, no difference to the placebo has been found.
prophylaxis
Retinopathy of premature infants can be prevented in that an attempt is made to prevent premature birth itself. The pregnant woman should seek advice on this from her supervising gynecologist (gynecologist).
In premature babies, the oxygen level in the blood should always be measured and regularly checked. Regular and frequent examinations by an experienced ophthalmologist are essential for the prognosis of the little ones.
Summary
Retinopathy of premature babies is a disease of the Retina due to the child's development not being advanced enough. The vessels that supply the retina with nutrients and oxygen in full-term babies are not yet fully developed. After birth In premature babies there is a risk that the increasing oxygen content in the blood will damage these few vessels. They are contracting. This is also called the Oxygen toxicity designated.
Usually are both eyes of the premature baby affected. Not only the severity but also the course of the damage is variable. The greatest damage is to be expected around the calculated due date.
With the little ones, not only the oxygen levels in the blood have to be checked, but also an experienced one Ophthalmologist should regularly mirror the fundus.
