Kids

Development of the eyeballs

   Starting from the development of the eyeballs, we can better understand certain eye problems such as myopia, hyperopia, astigmatism, strabismus, etc. but also the prevention and treatment appropriate to each age.
 

                                                                       Perfect vision increases the quality of life!

     Imagine sitting next to a person who sees only half (color and visual acuity) of a gorgeous aurora borealis, your reaction to the one who sees only half will convince you!
    Perfect vision = visual acuity 1.5 – 2.0, correct distinguishment of colors and perfect coordination of the eyeballs in binocularity.
 
     The eyeballs are formed around the 22nd day of life in the form of optical grooves, their development continues massively after birth, until around the age of three, and the ocular maturity is reached around the age of nine. It is important to know, because there are eye problems that can be easily remedied up to this age.
  • In the first month of life, the child does not have tears(the lacrimal glands are not developed), distinguishes up to a maximum of 20 cm, the angle of view is below 30 degrees and has no binocular vision, visual acuity about 0.5/10 or 5% is normal.
  • Children up to two months “are not interested” in objects at a distance of more than 40 cm, since they distinguish only shadows at greater distances, the cause of which is insufficiently developed eyeballs at this age. The eyeballs being smaller and having a high hyperopia, results in poor vision at great distances.
  • In the second month of life, tears begin to appear, vision increases by up to 60 cm and visual acuity increases to 1/10, very importantly, the child begins to distinguish colors, the first ones are red and green! We’ll see the importance of these colors along the way.
  • Up to five to six months, children can have an alternating strabismus because the eye muscles are underdeveloped.    After this age, stabilization of binocular vision occurs, and in the next month the angle of view will increase to 60 degrees.
  • At the fulfillment of the first year of life, visual acuity reaches about 4/10 and the angle of view as in the adult.
  • At three years of life, the children have relatively developed eyeballs, following a period of their slower growth, being also a favorable period for the first consultation if there were no problems and it was done earlier.
  • Around the age of 9 years the eyeballs are fully developed, including the eye muscles become rigid (attention to forays, tropes, amblyopies, etc. they can be relatively easily corrected up to this age).
 
       For newborn parents
     Returning to the development of eyeballs that continues relatively quickly after birth, you have probably noticed those projections on the ceiling in the children’s rooms, in the movies, they are not part of the director’s imagination, these projections attract the attention of children at different distances, from different angles, helping to improve the development of the eye muscles (without strabismus) and to increase the visual acuity.
 
    Subjective consultations begin approximately at the age of three, when the child can make certain visual differences (letter E or C turned left, up or down,) necessary for the correct assessment of visual acuity.
 
    At the moment, when the child already needs glasses but refuses to wear them, try to watch his reaction when he does not know that he is being watched. Leave their glasses at hand, promise a reward if he wears them and leave the location. If the child returns to their port and does not feel disturbed by them when he is alone (minimum 10 minutes) then it is probably a fad, otherwise ask for another expertise, do not force a treatment that probably does not correspond.
 
 
     What is astigmatism, how does it appear, how does it manifest itself and how do we correct it?
      Refractive vices such as myopia and hyperopia (index of refraction of refringent media in the eyeball and/or its size) are well known, myopia corrects with minus, hyperopia with plus, but what is astigmatism and what is its sign?
 
 
    
     The most widespread astigmatism is the corneal one, which is usually congenital (from birth) but can also be traumatic, arising from corneal injuries.
  The cornea is the first refringent medium of the eyeball from the outside to the retina, it is transparent and has the shape of a spherical caot.
     Pay attention to the wearing of contact lenses and possible corneal wounds, it “feeds” by ozmosis from adjacent tissues (choroid, sclera..), so it heals very hard.
      To explain congenital corneal astigmatism, we must go back to the beginning of the development of the eyeballs, in the second month of pregnancy, when they have the shape of a grain of rice, and the cornea is almost flat.

     In the following months of pregnancy, the cornea develops in the form of a spherical calotte, so at birth it must be as close as possible to a perfect spherical calotte.
      In approximately seven months of primary corneal development, in some people’s cases, a channel is formed by incorrect growth of the cornea in a certain meridian. Think of a bloated balloon, on which we put a floss and pull on its ends. The balloon will form a channel along the length and width of the floss. This is what a cornea with astigmatism looks like.
     This astigmatism can also occur monocular (only in one eye).
    
    Astigmatism is corrected with cylindrical lenses, which can be written with both signs, plus and minus, due to the translation between the two spheres that make up astigmatism.
    Cylindrical lenses can be described as spherical lenses with a certain power only in one meridian.
     Cil +1.00 at 90 degrees can be written: Sf +1.00 <> Cil -1.00 to 180 degrees (+1.00 90* = +1.00<>-1.00 180*)
 
 
 
 
      In preschoolers, astigmatism is manifested by poor eye-hands-to-foot coordination, tilts its head often and approaches the TV. In schoolchildren, you might notice they mess up the details at a distance and don’t see well on the blackboard. In primary school, they can read very well from the book at home, but they copy wrong or do not understand what is written on the board at school (myopia or myopic astigmatism), and in many cases children avoid saying this, in order not to get out of the “comfort zone” around their peers, or for other reasons.
 
 
            In general, parents with preschool children should be careful about signs that may indicate vision problems:
  • The child sits close to the TV,  book or mobile
  • He tilted his head often
  • Rubs the eyes often
  • Light-sensitive
  • He moves one eye, or both of them, inwards or outwards and does not look straight at certain times
  • Difficulties in coordinating the eye-hands-feet when playing(ball, bicycle…)
  • Avoids activities such as coloring, drawing, puzzles, activities with more details or an average complexity for the child’s age
  • Limited attention for the age of the child
 
            What can we do, as parents of preschoolers?
  • Play by throwing and catching the ball
  • Encourage activities where he uses eye-hand-to-foot coordination (in the house and outside: puzzle, block building, video games like Wii or Kinect, swimming, dancing, musical instruments, scooter, bicycle, ice skates, roller skates, etc.)
  • Simple memory games
  • Read them in a clear voice and a slightly elevated tone (the day) and let your child see what you are reading
  • Give it opportunities to color, cut(paper) to paste
  • Encourage interaction with other children
  • Pay attention to the time spent by the child in the near environment, frequent breaks, at a maximum of half an hour
 
      As you know, the consultations for the establishment our dioptres are done through two successive methods, Objective Testing and Subjective Testing.
    Objective testing, autorefractometry (dioptron) or testing at the “device” is by definition an objective test, so it does not take into account the opinion of the specialist or the patient. Through this method, we find out the basic dioptric values of the patient, values that will be used in the second stage of the consultation to the subjective method.
    Even if you use in a patient ten or more different devices, the values will be extremely close. So, the basic values of a patient are almost identical to any dioptron.
30-40 years ago, schiascopy was done (patient objective, subjective observer / specialist), with a light slit, non-invasive… which can give results extremely close to many modern objective appliances or techniques – if done correctly! Basically, with a candle and some shards of refractive glass, you can manage a correct objective test!
    Subjective testing is the cause of the appearance of different recipes for the same patient. The different interpretation of the specialist may be due to different testing methods and subjectivity of the patient. To eliminate these problems, we can use complementary tests, tests through which we can deduce if the patient answers our questions correctly!
 
                             The recipes of different glasses are just different subjective interpretations that relate to the same dioptric problem !
 

For more details please contact us