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Myopia or short/near-sightedness is when vision is blurry for distance and clear for near, such as, reading a book or looking at your mobile phone. However, the description is not as clear cut as blurry and clear vision. The description given applies to an individual under the age of 40 years, who has not developed other physiological conditions such as presbyopia (difficulty with near vision). Myopia is caused by an eye whose lens power is too strong for the length of the eyeball or whose eyeball length is too long. As a result, the focused rays of light merges to a point of focus which is in front of the retina rather than on the retina, giving a distant image that is out of focus. In order to get a clear image, negative lenses are added to the front of the eyes to focus the image on the retina.

There is no fixed age for the onset of myopia among minors. The onset of the condition starts from as early as birth, however, this is not the norm. Myopia has 3 types of onsets which is based on age; early onset which starts from about 3 years, typical onset starting from about 8 years and late onset, starting from about 14 years. The earlier the onset, the greater the progression of the condition resulting in higher power for the glasses. Adults can also develop myopia later in life. Clinical cases are now showing low levels of myopia that may develop in the age range of 30 to 40. Causality for this low myopia has not been established yet, but long hours of close work using the computer has been suspected as the probable culprit among the young professionals. Myopia can also develop in the elderly population prone to a certain type of cataract (nuclear sclerosis), which we refer to as reversal of their refractive power.

There are varying histories heard during an eye exam of how myopia is first suspected among patients, depending on the age on onset. In the infants to pre-schoolers, the history given is purely based on the parents’ observations, while older kids and teenagers describe their own symptoms. Infants’ vision is mostly based around their immediate surroundings; as a result, it may be difficult to identify slight “blurriness”. In general, signs that parents may notice that points towards myopia are:

Myopia is diagnosed through a sight test, where refraction is performed. The age of the child and their ability to respond to the practitioner determines the type of sight test required; cycloplegic or non-cycloplegic test.

Children’s attention spans are very short and their ability to focus on a given target is very poor. As a result of varying focusing points while they look around, their eye power also changes accordingly. This makes it difficultto find the true power of their eyes in its relaxed state (when the eye focuses on a distant target), thus the need fora cycloplegic refraction.

A cycloplegic sight test is one where the optometrist uses an eye drop called cyclopentolate or homatropine to relax accommodation in the eye and allows the power of the eye to manifest. This type of test gives an accurate prescription without the need for the patient to provide answers. It is done on infants and younger kids or even older kids who cannot understand and relate to the test.

A child’s risk of developing myopia and the final refractive power of the eyes can also be estimated based on the findings of a cycloplegic refraction.

A non-cycloplegic test is one where the use of eyedrops (cyclopentolate or homatropine) is not required as the child can respond accurately to give the required result for the power of the glasses. A such refraction is possible on older children from around the age of 6 upwards. However, the practitioner will judge the response of the child and determine whether drops are required or not.

Myopia is detected through a sight test while performing refraction. This consists of putting lenses in front of the eyes until the point of focus is on the retina, hence a clear image is found. However, myopia is not a condition that reverts or goes back to normal where no glasses is required in the future. As mentioned previously, the risk of other complications associated with it, increases the higher the myopia is.

Myopia is easily corrected with glasses which should be worn constantly. As the child gets older to an age where they are responsible enough, contact lenses also become an option. However, this should not replace glasses entirely as both should be used at different times.

Myopia is a condition that progresses and there are interventions to slow down its progression such as an eye drop containing a very low dose of Atropine. Topical atropine (eyedrops) has the same action as cyclopentolate or homatropine but in a much lower dose. Myopia research has proven that very low dose of atropine (0.01%) has the most beneficial effect in slowing down myopia progression, hence it is our drug of choice in MIOT TOTAL EYECARE. Atropine 0.01% has been shown to reduce the progression of myopia by 59% in children aged between 6 to 9 years. The low dose of atropine preparation is such that it does not cause the side effects of the usual drops such as homatropine and cyclopentolate.

Visual therapy covers a variety of ways in which the aim is to improve the final standard vision with or without glasses. In myopia, there are different scenarios that can arise for powers of the eyes such as: simple myopia (physiological or high), myopic astigmatism of low, moderate or high level, or a mixture of both myopia and astigmatism of low, moderate or high. Simple myopia and myopic astigmatism can also have large power differences between the eyes (anisometropia). In most cases of simple myopia that hasalmost equal power of the eyes,standard of vision develops to its maximum as near vision will be clear even if distant vision is blurry. However, in cases where there is complex powers for the eyes such as large differences in powers between the eyes, the higher powered eye may not develop good vision orin moderate to high astigmatism, both eyes may not develop good vision if not corrected by glasses. Both scenarios requires the eyes to be corrected at an early age, prior to 8 years for good standard of vision to fully develop. There are options such as soft contact lenses, rigid gas permeable contact lenses, glasses or a combination of contact lenses and glasses depending on the prescription and what is tolerable by the eyes and the brain.

Myopia predisposes the eyes to other risk factors such as retinal detachment, cataract, glaucoma and certain other retinal conditions.

The onset of myopia follows a trend upon which it accelerates and then slows down but does not reverse. Hence, wearing glasses does not “get rid” or “cure” the condition, but provides a clear image for the brain to process and develop vision. Progression of myopia will happen despite wearing glasses, but the speed of progression and the final power of the eyes depend upon lifestyle, genetics and using accurate correction. It is important to note that many eye conditions have overlapping symptoms. Parents should always bring their child for a sight test to rule out any existing conditions that may arise ranging from the front to back of the eye. There is no clear-cut age as to when a child should have their first sight test, but it is advisable before the age of 3 years. Uncorrected refractive error beyond the ages of 7 to 8 years may end up causing a lazy eye. Children’s visual development is critical and any refractive error prior to the age of 7 to 8 should be undertaken to ensure good visual outcome.