Vision problems in children generally are not the direct cause of learning disorders; however, they can interfere with children’s abilities to perform to their potential. Regular eye examinations are essential to evaluate the functional status of the eyes and visual system, and to counsel and educate parents/caregivers regarding their child’s visual, ocular, and related health care status.

The important eye diseases which may be detected by a regular ophthalmic examination include refractive error, amblyopia, anisometropia, nystagmus, nasolacrimal duct obstruction, retinoblastoma and developmental glaucoma. Just as responsible parents adhere to an immunization schedule, regular eye examinations by an eye-care professional must be incorporated into the preventive health care plan for children.

The following is the recommended schedule for eye check-ups in children:

At birth

Screening by paediatrician for all, ophthalmology consultation if required

Birth to 24 months

Asymptomatic/ risk-free: At 6 months of age

At-risk: At 6 months of age or as recommended

2 to 5 years

Asymptomatic/ risk-free: At 3 years of age

At-risk: At 3 years of age or as recommended

6 to 18 years

Asymptomatic/ risk-free: Before first grade and every 2 years thereafter

At-risk: Annually or as recommended

In addition to the tests performed routinely for adults, a paediatric eye exam consists of a comprehensive visual acuity recording, cycloplegic refraction and fundus, assessment of binocular vision, accomodative function and ocular motility. Intraocular pressure measurement, syringing and probing of the nasolacrimal duct, detailed tests for stereopsis and visual field assessment may also be performed when indicated.

An eye exam during pregnancy is not mandatory. Your obstetrician decides if you need an eye exam, and will invariably refer you to an eye doctor if you have high blood pressure or diabetes. In these expectant moms, any change in vision may signal an emergency

This is because both high blood pressure and blood sugar can affect the eyes, especially during pregnancy.

Preeclampsia, a potentially serious problem that occurs in 5% to 10% of pregnancies is characterised by high BP and the presence of protein in urine. It can result in vision changes ranging to a  temporary blur to loss of vision, sensitivity to light, auras, and flashing lights.

Any of these symptoms means you should call your doctor immediately and go to the hospital emergency.

Diabetes, on the other hand, can lead to changes in the retina which do not threaten your general wellbeing, or the baby’s; but can potentially affect vision.

Also, the fluid retention during pregnancy can change the thickness and shape of your cornea, and result in blurry or distorted vision. Usually, these changes are temporary, and your vision becomes normal  after pregnancy or after you stop breast feeding.

If your vision alters significantly, however, talk to your doctor. You may need to change your prescription if you wear glasses. Usually the shape of your cornea will revert to normal after your pregnancy is over.

You will also notice that your eyes maybe drier than normal, and there may be an associated discomfort. Dry eyes can make wearing contacts irritating and uncomfortable.

You may use artificial tears which are available over the counter, to lubricate your eyes. Some artificial tears may have preservatives so, check with your doctor first to make sure the ingredients are safe for you during pregnancy.

Video: Eye Care during pregnancy

The WHO Global Initiative to Eliminate Avoidable Blindness, “VISION 2020: The Right to Sight”, aims to eliminate these diseases as a public health problem by the year 2020. These diseases, along with uncorrected refractive errors, may be controlled since they have effective strategies for elimination and control. The most important of these is cataract, and other diseases include glaucoma (12.3%), age-related macular degeneration (AMD) (8.7%), corneal opacities (5.1%), diabetic retinopathy (4.8%),

Cataract is the leading cause of visual impairment worldwide (47.9%), except for certain developed countries. Cataract results from a clouding of the lens of the eye, causing decrease in vision.  Cataract is normaally an age related change in the lens, but disease such as diabetes, and trauma, can accelerate cataract formation. Cataracts can affect any age group, even newborn children.

Cataracts are easily curable with surgery, and the newer cataract surgical techniques are safe and effective. Since many people do not have access to medical care, cataract remains a significant public health care burden.

Glaucoma usually results when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. It is usually asymptomatic in the initial stages, and a comprehensive eye exam alone can detect it.

There are two kinds of glaucomas, angle closure being more common in south-east Asians, while the open angle variant is more common in Caucasians. The incidence of blindness due to angle closure disease is almost three times that of the more common open angle glaucoma. As of now, there is no “cure” for glaucoma but early diagnosis and treatmentcan control the disease process so that blindness may be prevented.

Age-related macular degeneration (AMD) results due to the development of abnormal blood vessels at the macula (Wet AMD), or death of light-sensitive cells at the macula (Dry AMD). The macula is the most light sensitive part of the centre of the retina, which is responsible for perception of finer details and central vision. AMD therefore results in loss of central vision, unlike glaucoma which affects peripheral vision first. The disease is not preventable, but can be treated. Treatment of AMD involves injections into the eye (Lucentis and Avastin; Ranibizumab and Bevacizumab, respectively) and/or lasers.

Corneal diseases result in corneal scarring, and decrease/ loss of vision, especially in children and young adults. The main causes include trachoma, trauma, onchocerchiasis and corneal ulcers. Most of these diseases are preventable and curable in the early stages with relatively minor interventions. The WHO programs for the prevention and management of trachoma and onchocerciasis aims at providing eye health care to vulnerable groups, especially in parts of Asia and Africa. Visual rehabilitation of these patients usually requires a corneal transplant.

Diabetic retinopathy is  usually asymptomatic, and it is therefore essential for diabetics to undergo an annual dilated retinal evaluation.

Diabetes can cause abnormalities in the small blood vessels in the retina, including new blood vessel formation,resulting in leakage and bleeding from these vessels. If this leakage is at the macula, the most sensitive part of the retina, loss of vision results. Diabetic retinopathy may be treated with lasers, injections into the eye, and/or surgery. Blindness due to diabetes is largely preventable with timely interventions and adequate blood sugar, blood pressure and cholesterol control.

The WHO database from 2002 provide the first estimates of global burden of visual impairment:

• Globally, in 2002 more than 161 million people were visually impaired, of whom 124 million people had low vision and 37 million were blind.

• In this statistic, refractive error as a cause of visual impairment has not been included, which means that the actual magnitude of visual impairment is significantly more.

• For each person who is blind, an average of 3.4 people have low vision (regional variation ranging from 2.4 to 5.5).