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Elizabeth wrote:
Last month my daughter had an aye examination. The results OD: Sphere +5.00 Cylinder -4.00 Axis 166 OS: Sphere +5.00 Cylinder -3.75 Axis 020 Our optometrist toll us that she has farsightedness and astigmatism. I found this information in your website "Farsightedness usually decreases as a child ages, typically normalizing to a negligible value by the age of 7-8", so my question is, Does she have to use glases now? She is 4 years old. Thank you
Dr. Sally Aldayeh's response:
Ei Elizabeth,
I like your question, The above prescription in my opinion must be introduced to your 4 yr old everyday slowly and eventually worn full-time ( Adaptation period). Please watch out for any adaptation problems, there should be none after 2 weeks. This prescription is usually given to children mainly as a treatment, and to allow full brain to eye development. I would also recommended you see your optometrist again in at least 3 months for a follow up visit, then if things are fine, see your optometrist annually. Thank you Elizabeth
Dr. Sally Aldayeh
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Daughter has Hyperopia
Michelle wrote:
My 3 year old daughter has just been diagnosed with hyperopia. Her prescription is +2.00 left and +5.00 right. The optometrist did do a cyclopegic test. Can you please explain why she was not able to see things when tested at a distance with the right eye? Is this because of amblyopia secondary to the hyperopia? I am having a hard time understanding why her distance vision seemed so poor on testing when she is "far-sighted" and supposed to be able to see at a distance better than up close. I also have a hard time understanding why she can string small beads and colour well when she has such poor vision. Also, can you please comment on whether the +2.00 eye should be corrected as some of the posts indicate that <+4.00 are often not corrected at this age. Thank you.
Dr Henry Smit's response:
Dear Michelle: You are correct in suggesting that your daughter does not see well at distance with the right eye because she has amblyopia secondary to hyperopia. To be more specific, however, your daughter has amblyopia in her right eye because she is significantly more hyperopic in her right eye than in her left eye. In the vast majority of cases of amblyopia that I have seen, there is a significant difference in the prescriptions of the two eyes, and it is almost always the eye with the greatest degree of farsightedness that has amblyopia. The simple explanation for this is that the human body is “intrinsically lazy” – that is, our bodies do the least amount of work required to “get the job done”. Your daughter is farsighted in both eyes, and has to exert some focussing effort to get a clear image. In order for her to perceive a clear image, she has to exert 2 dioptres of focussing effort to get a clear image in the left eye and 5 dioptres of focussing effort in the right. When she focuses 2 dioptres worth, her left eye will be in focus and the right eye will still be 3 dioptres out of focus. When she focuses 5 dioptres worth, her right eye would be in focus, but her left eye would be 3 dioptres out of focus. As it is much easier to exert 2 dioptres worth of focussing effort than it is to exert 5 dioptres of focussing effort, she has naturally focussed just enough to get her left eye in focus, continually leaving the right eye 3 dioptres out of focus. As her visual system developed, it did so in a way that newly formed neural connections in the parts of her brain dedicated to vision had a “preference” for receiving vision from her left eye which was consistently more clear than the information it was receiving from the right eye. As a result, her brain is not as able to interpret visual information from the right eye, a condition that we call amblyopia. Although amblyopia is most often considered an eye condition, it is probably more accurate to think of it as a perceptual dysfunction of the visual part of the brain. That is why the main component of the treatment of amblyopia involves a “re-training” of the visual brain to overcome its preference for receiving visual information from only one eye. Treatment takes time (months – years) and usually involves patching the better eye, forcing the brain to learn to better/normally interpret information received from the amblyopic eye. I would expect your daughter to have poor distance vision in the right eye because of her amblyopia, but normal distance vision in the left eye. Most 3 year old children have a range of accommodation (focussing ability) of 10 dioptres or more, so your daughter would easily be able to focus her left eye 2 dioptres in order to see clearly in the distance. For her to see clearly at near, she would have to focus an extra 2 to 4 dioptres, still well within the normal focussing ability of most 3 year olds. That explains why she is still able to see well up close despite being “farsighted”. Regarding the need to correct your daughter’s left eye with only 2 dioptres of hyperopia, your internet research is valid, in that if a child has 2 dioptres of hyperopia in BOTH eyes, it is most often not corrected. However, when there is a significant difference in correction between the eyes (anisometropia) it is conventional/preferred clinical practice to correct both eyes so that each eye can receive an in-focus image at the same time, enabling better development of binocular coordination and stereoacuity. Hope this is helpful. Dr. Smit
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Re: Daughter’s Prescription Lower than What She Needs
Amie wrote:
I noticed my 2.5 year old daughter doing a lot of exaggerated blinking lately, so I took her in for an eye exam. I was told that she needs glasses. Her prescription is +5.75 in one eye and +6.25 in the other with slight stignatisms in both eyes. I was told that the prescription written is lower then she actually needs to give her eyes room to adjust as she grows. I've been doing a lot of research on farsightedness and I was wondering if a child with her type of vision problems needs to have glasses. If she doesn't get them is there more of a chance that she will outgrow some of the farsightedness? Her eyes are straight and she seems to be able to see everything close up and far away. Any insight you can give me into this would be great thanks!
Dr Langis Michaud's response:
Dear Amie, This is a very good question. Thanks for asking it. Your optometrist is perfectly right to say that at +5.75 and +6.25 your child needs glasses. Farsightedness creates an image that is focused back from the retina. Eyes have to adjust their “power” to refocus that image at the appropriate point on the retina. This is done with the effort of the crystalline lens. Over +4.00, many studies have proved that the effort to compensate farsightedness is too demanding for the visual system. At near, you have to add +2.50 to the visual demand at far. That means that your daughter has to compensate +7.25 and +8.75 at near! She can, but she is already rapidly developing visual fatigue… OR she compensates by not looking for a long time at near or doing many things at the same time. Some parents think their children are hyperactive but in fact they are just hyperopes… She also develops a tendency to look at near at a closer distance than normal. This is linked to the fact that for every dioptre the child has to compensate the eyes turn inward by 6 degrees. For a natural demand of +2.50 to +4.00, a regular reading distance is maintained. At +7.00 or +8.00 your daughter is focusing and seeing well at near only if she is at less than 12 cm! Very close. Further than that, she would see double since the eyes crossed at this distance. In the long term, it is not possible, with such a problem uncorrected to learn to read efficiently and to maintain near work for more than 1-2 minutes. Many children drop out of school simply because their visual system cannot handle the demand. Even if the child seems to see well, high hyperopia is known to be amblyogenic, meaning that without the appropriate correction the eyes will never develop to their optimal level. We can translate that by the fact that, without correction, these eyes will remain at 80-85% of their capacity and that further on the binocular vision and the 3D vision will be also reduced. This is sad because that can cause reading difficulties, headaches while doing computer work and this reduced capacity can also make the difference in career choices: a policeman, a firefighter or an aircraft pilot have to have 100% percent vision with full 3D vision. Under +4.00, habitually we do not correct and we observe how the eyes are developing between 2 and 8 years old. This is the critical period when eyes have to be appropriately stimulated in order to fully develop their capacities. This period of development is known as the emmetropization phenomenon. This means that whatever the visual problem is from birth, the eyes tend to compensate for it in order to get perfect unaided vision at 8 years old. When you are under +4.00 this phenomenon should not be altered and to prescribe glasses could interfere with “nature”. This is another story over +4.00, which is the case of your daughter. Considering that the eyes don’t have the possibility to fully develop their potential, emmetropization is cancelled. This is also true for myopia over 5.00D and astigmatism over 1.50. Yes, just 1.50 because astigmatism is way more disturbing for the visual system than spherical refractive errors such as farsightedness and myopia. The way to prescribe glasses has to take in account the age of the children. This is true that, for hyperopes (farsightedness) we have to lessen the amount of the full correction by the normal visual demand at near. For a younger child, like your girl, a +2.00 reduction is OK. Older than that, this reduction will be +1.25. To get the right script, it is necessary to perform a cycloplegic refraction. This means that the optometrist or the ophthalmologist will put some drops on the eye of the patient. This aims to alleviate any compensation of the refractive error by the natural lens of the eye, the crystalline lens. Once done, this test allows us to assess the “real” amount of hyperopia on which to base the prescription. It is not rare to find +2.00 to +3.00 higher values compared to the test done without cycloplegia. For instance, if with that test your daughter is +6.00 at far, I would start the prescription at +4.00 and see how the eyes will develop. IMPORTANT: These glasses have to be worn ON A FULL TIME BASIS. ALWAYS. With time, this prescription will be updated according to the evolution of the eyes. In the long term, most of the hyperopes, well corrected with appropriate glasses, will be back on the emmetropization pathway. This means that the system will adjust to lessen the amount of hyperopia over the years. Most of the hyperopes cease to wear glasses by the age of 12-15 but again this is unique to each patient. Genetics play a big role here. Some patients will remain hyperopes, no matter if they wear glasses or not at a younger age. Again, glasses will not do anything but good for the development of your children. This is a misconception that eyes can be made stronger by leaving them without correction. The visual system is not built that way. Consequently, my recommendation are the following: 1) Re-consult your optometrist if the first exam was not performed with drops. 2) Follow his recommendation — it seems that you are in very good hands considering the recommendations he gave to you. 3) Your daughter should wear her glasses on a full time basis. Her future in school depends on the way you deal with her hyperopia NOW. 4) Make regular follow-ups until the age of 8 to confirm the full development of the eyes. 5) Make annual follow-ups thereafter. 6) Contact lenses can be considered by the age of 8 for most of the children. There are a lot of benefits and self-esteem of the children is boosted as a consequence. Many studies were done in the last years that prove this. Thanks for sharing that with us. Hoping that this will help, Dr. Langis Michaud, OD, MSc, FAAO (Dipl) Associate Professor Université de Montréal
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