Common Eye Care Terms

Definition: A vision condition in which images come to a focus behind the retina of the eye and your eye muscle must focus to make the object clear. Vision is usually better for distance than for near objects.

Hyperopia = farsightedness. These two terms are often thrown around and mean the same thing.

Hyperopia is when the light entering the eye focuses behind the retina, and muscles in your eye have to work to make the image appear clear on your retina.

Hyperopia is the most common refraction in the world, and almost every child is born farsighted.

Too much hyperopia can cause problems by increasing effort when reading, looking in the distance, or transitioning between the two. It can also lead to visual fatigue at school and work, tiredness, and headaches. Excessive hyperopia can also lead to a turned eye known as strabismus.

In later life, mild amounts of hyperopia can contribute to increased glare with driving, problems watching TV, the need for stronger reading glasses, or the need for reading glasses at a younger age.

Biggest Myth: If you’re farsighted, you don’t need glasses to see in the distance; you only need glasses to read.

Definition: A vision condition in which the light entering the eye comes to a focal point in front of the retina, resulting in blurred vision of distance objects.

Myopia = Nearsightedness. These two terms can be used interchangeably.

Definition: Reduced vision out of an otherwise healthy eye. Commonly seen in children as a result of a turned eye or an unequal prescription between the two eyes.

Amblyopia is often referred to as a lazy eye and is a common vision condition we see in children. It can affect up to 4% of the population and is one of the reasons we recommend early eye exams by an optometrist.

Amblyopia (lazy eye) is usually caused by an eye that turns in or out, but it can also be caused by an imbalance between the eyes where one eye has a stronger prescription than the other. Sometimes, it may also be caused by a medical condition like cataracts.

Symptoms of amblyopia in children can include: Rubbing eyes, closing one eye, problems with depth perception (doesn’t like 3D movies or has problems catching a ball), an eye that seems to turn in or out (more noticeable when tired), crying or fighting when one eye (the good eye) is covered.

Most amblyopia can be corrected or managed with early diagnosis and treatment. However, treatment success does decrease over time, making early diagnosis more critical.

Definition: A vision condition caused by a deviation from spherical curvature in the eye or lens results in distorted images, as light rays are prevented from meeting at a common focal point.

Astigmatism causes a lot of glare, which leads to squinting. Even a slight amount of astigmatism can throw off your vision.

Astigmatism means that your eye is focusing light on two separate points in the back of your eye. If one of those points falls on your retina, your vision might seem pretty clear throughout the day. However, in dim light, astigmatism might lead to a lot of visual blur and ghosting images, resulting in problems with night driving and reading in low light. In addition, uncorrected astigmatism may contribute to headache-like symptoms.

It’s estimated that 1 in 3 people has some degree of astigmatism.

Definition: The loss of the ability of our eyes to change focus or inability to focus on objects up close.

Presbyopia is a normal process where we lose the ability to change focus. Inside of our eye there is a physical lens that lives behind the coloured part (the iris). Overtime this lens hardens and becomes less flexible and is no longer able to change its shape.

This process is gradual, although patients normally notice this change seemingly over night. This happens to everyone once we get into our 40’s.

Typically this is best corrected with a progressive lens or reading glasses.

Single-vision lenses are eyeglass lenses with consistent prescription power throughout the entire lens, providing clear and precise vision for a single distance, such as reading or distance vision. Optometrists prescribe these lenses to correct common vision problems like nearsightedness (myopia), farsightedness (hyperopia) or astigmatism. Single-vision lenses are ideal when one specific vision correction is needed, with no requirement for multifocal capabilities like bifocals or progressive lenses.

Bifocal lenses are eyeglass lenses that have two distinct prescription powers in a single lens. Typically, the upper portion of the lens is designed for distance vision, while the lower portion is intended for near vision. Bifocals are commonly prescribed to individuals who require correction for both nearsightedness and presbyopia, a condition that affects the ability to focus on close objects as one ages. These lenses allow users to see clearly at different distances without the need for multiple pairs of glasses.

Progressive lenses, also known as multifocal or no-line bifocal lenses, are eyeglass lenses that offer a seamless transition between multiple prescription powers within a single lens. Unlike traditional bifocals or trifocals, progressive lenses do not have visible lines dividing the lens into distinct zones for different vision needs. Instead, they provide a smooth, gradual change in prescription from the top (for distance vision) to the bottom (for near vision), allowing wearers to see clearly at various distances, including intermediate ranges. Progressive lenses are commonly prescribed to individuals who require correction for presbyopia and those with a need for vision correction at different focal points. They offer a more natural and aesthetically pleasing solution for multifocal vision correction.