While this is a somewhat simplistic explanation, it gets the point across easily. Your eye is built like an old camera, with a lens in the front, and camera film (retina) in the back. The light is “focused” by your tear film, cornea, and lens to be exactly focused on the retina.

However, if your eye is too long, this is called MYOPIA (nearsightedness, shortsightedness). Yes, it was poorly named and everyone gets it confused. Just remember a nearsighted / myopic eye is an eye that grew too long in childhood, so you need glasses/contacts to make the incoming light reach the back of the retina of the longer eye. In a glasses prescription, myopia is indicated with a NEGATIVE number; the more minus the number the longer the eye is.

You’ve likely guessed that HYPEROPIA (farsightedness) is an eye that is too short (didn’t grow long enough during childhood). Therefore, we use glasses/contacts to bend the incoming light more to focus on the closer retina in the shorter eye. In a glasses prescription, hyperopia is indicated with a POSITIVE number. The more positive the number, the shorter the eye is.

NO, it does not make sense that a shortsighted eye it too long, but that is how they named it many centuries ago in 1622 ! It has been confusing everyone for 400+ years since.

Just like shoe size your feet have a length (eg size 11 shoe) but also a width (A,B,C,D,E). So, a Size 13 D shoe fits a long, wide foot, whereas a size 7 A shoe fits a short, narrow foot.

Eyeballs have a length AND width just like feet. The length (myopia…too long; hyperopia… too short)...and width of the eye is: ASTIGMATISM A nice round eye has minimal astigmatism, whereas a squooshed eye is high astigmatism.. Astigmatism is called “cylinder” in your glasses rx and it has 0-180 degrees of directionality to it, depending on which direction your eye is squooshed. In a glasses prescription, the amount of astigmatism is indicated as NEGATIVE CYLINDER and is followed by a direction (0-180degrees). The more negative the cylinder number, the more squooshed the eye is.

Finally, there is presbyopia, which has nothing to do with the length or width of the eye. Presbyopia is a loss of the ability to “focus” up close with your lens inside your eye. Normally, in young people, the lens inside the eye is “relaxed” to look in the distance at the concert stage, and then it “balls up” to focus up close on the concert program handout. When you are young, this can be done instantly and easily with instant auto-focus. No effort needed. But as we get older, our lens inside our eye loses the ability to “ball up” to see things at near…so then we need to wear “extra” near power in our glasses (reading glasses, or the “add” of a bifocal) to do the near focusing for us.

So, in summary… eyes can be too long (MYOPIA) or too short (HYPEROPIA) and / or too squooshed (ASTIGMATISM). Just like your own body shape, which is often inherited from your parents, the same can be said for eye shape. Tall parents tend to have tall kids; Parents with long eyes (myopia) tend to have kids with long eyes (myopia). Parents with squooshed eyes (astigmatism) tend to have kids with squooshed eyes (astigmatism). It’s not 100% inherited perfectly, but it is a strong inheritance pattern. Yes, there are parents with really long eyes who have 3 kids that don’t need glasses, and similarly there are parents who have never needed glasses (perfectly shaped eyes) who have children who all need glasses. But that’s fairly rare. Genetics can be a funny thing sometimes !!

As much as it may seem like smoke and mirrors, there is quite a bit of science and optics to determining a child’s refractive power (and therefore their need for glasses (or not). Since children have an AMAZING power to “overfocus”, thus giving false impressions of the power of the eye and a subsequent inaccurate glasses prescription.

The only official away around this in children and adolescents (up to about age 16-18 yo) is to take away the ability of the patient to “overfocus.” This is done with dilating eyedrops, which “cycloplege” or “stop the muscles involved in eyeball focusing from working.” Basically, we have to intermittently dilate young people to get a truly accurate refractive power. While glasses prescribing can be a little witchcrafty in children, getting the most accurate numbers possible tilts the odds in our favor of getting an accurate and wearable and non-headacheable glasses prescription.

The drops sting a little. They don’t sting as much as the dramatic response that some kids give to them, but they don’t feel pleasurable, for sure. But really not that bad and nothing to be all worked up about. PS. the drops sting a little because of the pH of them (they are a little acidic). Whoever invents a short-acting dilating eyedrop that doesn’t sting will have a goldmine and my eternal thanks. Here at Pediatric Ophthalmology (POASF) we are committed to getting the most accurate exam possible on your child. This can be a little time consuming depending on the cooperation level, but we believe an accurate healthy eye exam is essential. Call us at (540) 681 1211 to set up an appointment to have your child’s eyes examined.

A standard glasses prescription is composed of 3-5 components:

- sphere (how long or short the eye is)

- cylinder (astigmatism)(how squooshed the eye is)

- axis (only in astigmatic eyes, denotes the direction from 0-180 degrees of the squooshed area of the eye

- add power (this is the amount of bifocal to help with near focusing, mostly in old people, but also in children with eye crossing, to help avoid crossing the eyes with near focusing. Bifocals can be either “lined” or “lineless” (blended, progressive)

- prism (this is vertical or horizontal displacement of the image to help people with double vision see “single”)

A glasses rx may look like: +3.00 -1.75 x180 +2.50 add (this is an rx for a farsighted eye, with some astigmatism at 180 degrees; also a +2.50 bifocal at the bottom of the lens; no prism.

Another glasses rx: -8.00 -4.50 x 155 (this is an rx for a really nearsighted eye with a ton of astigmatism at the 155 degree meridian; no bifocal, no prism)

Another glasses rx: -3.00 sph (this is an rx with just a long eye, but no astigmatism, no bifocal, and no prism)

Many people are confused about the importance of eyeglasses for children. Some believe that if children wear glasses when they are young, they will not need them later. Others think that wearing glasses as a child makes one dependent on them later. Neither is true.

Wearing shoes does not make you dependent on them, other than the fact that you get dependent on the comfort of not walking on stones and pebbles all day. You can take your shoes off anytime you want, though if you are running across pavement, you will be much less comfortable.

Same thing for glasses. Your child’s glasses prescription is just like a shoe size. The glasses rx is just a bunch of numbers that describe the shape of your child’s eye (see above: understanding your child’s glasses rx) and a pair or glasses or a shoe gets made to whatever shoe size or glasses numbers/eye shape your child has. The shoes do NOT change your child’s foot size, just make it more comfortable to walk. Mother nature and growth are what change your child’s shoe size. Similarly, glasses do NOT change your child’s eye shape. They are made to “fit” the shape that your child’s eye has currently. Glasses don’t make your eyes grow or shrink…mother nature, growth (a lot dependent on genetics) are what makes your child’s eye grow and therefore need different glasses as they age.

Eyes only GROW during childhood, they never shrink. Eyeglass prescriptions are all centered around “0”, which indicates the perfectly sized eye that refractively does not need glasses to see (neither too long nor too short).

But, if your eye is too short in childhood (farsighted, hyperopia), AND you are growing…you may actually outgrow your farsightedness, because your short eyeball is growing longer. These are the people you meet who say “yes, I had glasses as a child, but I outgrew them.”

Unfortunately, if your eye is already too long (nearsighted, myopia) in childhood AND you are still growing, your already long eye will grow even longer…making it seem as if your nearsightedness has gotten worse. It did not, your eye just grew. (When your shoe size increases, your foot didn’t get worse or less healthy, it just “grew”. ) Same for eyeballs.

So, answer the question “will my child outgrow their glasses if they wear them” or “become dependent on them if they wear them” the answers are:

-your childs short eyeballs (farsightedness) may grow long enough to outgrow farsightedness (giving the false impression that they are getting better)

-your child’s long eyeballs (nearsightedness) will never outgrow their nearsightedness, and their eye will get longer still as they grow (giving the false impression that they are getting worse)

-as far as being dependent on them, the best analogy is the winter coat in 25 degree weather. Yes, you can be outside in 25 degree weather without a coat, but you’ll likely be cold. If you put a coat on (ie put on glasses) you will be warmer (ie see better) but you can take your coat off (glasses off) any time you want, but you will be cold (blurry). Most of us, even middle school boys, will eventually put a coat on if it gets cold enough. Similarly, your child will eventually wear their glasses when they feel they are blurry enough. Admittedly, though, there is a wide tolerance for “blurry vision”, just like there is a wide range of tolerance for spicy food and room temperatures. Add in the fact that cranky teenagers may be more concerned about “their look” than “their vision”. They will eventually come around. In the interim, this is why parents have gray hair and short tempers.

Just because your child failed a vision screening does NOT necessarily mean that they need glasses or that there is anything wrong. But, there may be. The technology of vision screening equipment has allowed screening of younger and younger children and the goal of screening is to “cast a wide net” so as not to miss any child with any eye issue whatsoever. This means that sometimes, healthy kids with healthy eyes get caught in the “screening net.” The only way to know for sure, especially if your child has been flagged on a vision screen, is to have your child checked out, including a dilated cycloplegic refraction exam (a quick “undilated” first time exam will likely yield unreliable and false results and will often times result in kids getting prescribed eyeglasses when they didn’t really need them). We hear it all the time: “she was prescribed glasses last year, but she never wore them and states she doesn’t need them” A dilated cycloplegic refraction is the answer, coupled with any symptoms (if any) the child is experiencing. In a nutshell, here at Pediatric Ophthalmology (POASF) we understand this phenomenon. Some kids “want” glasses, and some kids desperately “do not”. The cycloplegic refraction, coupled with the visual acuity and symptoms, cuts through all that and gets down to the science and the numbers. Our goal is always to avoid glasses in children if we can, or if the child is borderline, to give the prescription but with full disclosure to the parents that some borderline refraction kids will wear them and some won’t, so spend accordingly. Since we do not dispense or sell glasses at POASF, we have no secondary gain to prescribing glasses or not. We do what is best for our patient!

Other reasons to fail a vision screening may be unequal pupils, or possible alignment issues, or a poor red reflex. Sometimes, though, the kiddo was just having a bad day when the school nurse checked the vision. All of these possibilities need to be checked out. If your child has failed a screen, have their eyes checked with a dilated exam. Rest assured, we will get to the bottom of it.

Upon arrival to the office, our front desk personnel will review any paperwork that needs updating (let us know if you have moved or changed your email address or phone number, or if you have any changes to your HIPAA forms or (very importantly) or want to make any changes to “who is allowed to bring your child to their appointment”.

Then, we will try to use a machine that gives a prediction of your child’s (dry/undilated) refractive status. These aren’t terribly accurate in kids below age 14, but we do them because the info does help a little from an astigmatism standpoint.

Next, we will go to an exam room and talk about why your child (or you if here for adult strabismus) is here and discuss any important things you’ve noticed about your kids vision or visual behavior. We’ll want to know any pertinent family / social / and past medical history, especially any sort of eye issues that run in the family (particularly high myopia).

We’ll then do some testing for visual acuity, binocular function, eye movements, eye alignment, etc. If your child is too young to know their letters, we have appropriately sized shapes that we use, or other methods to get a flavor for how their visual status is in each eye. We usually use the slit lamp to check the front of the eye at this point, if the child will allow it. Some will and some won’t, though we do specialize in getting kids to cooperate (we are not 100% successful…but pretty close).

Then, if you are a new patient or are here for a return annual checkup, dilating drops are used to dilate the pupil for examination of the inside of the eye and to allow accurate measurement to see if glasses are needed (see other places on this website for “why we dilate” and what we learn from it). The drops don’t feel so great to children (sorta like shots don’t) but they are a necessary part of most pediatric exams.

It takes about 20-30 minutes for your child’s eyes to dilate. Then it's back to the refracting machine, followed by a manual retinoscopic refraction by Dr. Pav to do any tweaking. Another look at the now dilated eye with the slit lamp, followed by a look at the retina both with the slit lamp if we are able and the headlamp.

Depending on the cooperation level of your child (and the cooperation level of the children that were scheduled in front of your child) and any emergencies that got added on in front of you, one should expect a new or annual dilated exam to last between 1-2 hours, and a return undilated checkup about 20-35 minutes, depending on the problems being addressed. Dr. Pav makes a sincere effort to stay on time, but uncontrollable factors often conspire to make that goal elusive. If your child’s appointment has been delayed by an emergency situation, we apologize and ask that you remember that one day, that emergency patient may be your child.