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FYidoctors Dictionary

Posted on January 20th, 2022

The world of optometry is full of words and phrases that are not part of most people’s everyday language. Many optometry terms are rooted in Latin and can often be difficult to spell and pronounce. That being said, in order to optimize your eye health, it’s important to know and understand some basics. We’ve compiled an “FYidoctors Dictionary,” containing common eye-related words and concepts that will help make the optometry landscape a breeze for you to navigate. 

Basic terminology 

Depth perception: Depth perception is the ability to see things three-dimensional. 

Intraocular: Intraocular refers to anything that occurs within or is administered to the inside of the eyeball.

Ocular: The term “ocular” indicates anything that is related to the eyes or vision. 

Oculist: Oculist is another word to describe an opthamologist or optometrist.

Opthamologist: A medical doctor that specializes in surgery and treatment of eye diseases.

Optometry: Optometry is the profession of examining the eyes to detect any visual defects and prescribe corrective measures, medications, and lenses when needed.

Optometrist: An optometrist is a primary care doctor who examines, diagnoses, and treats eye conditions. Unlike opthamologists, optometrists do not perform surgical treatments.

Peripheral vision: Peripheral vision refers to a person’s sight that extends beyond the central field of vision, enabling them to see objects to the left or right and up and down without having to move their eyes or head. 

Eye parts 

Anterior chamber: The anterior chamber is the frontal portion of the eye, situated between the cornea and the iris. 

Aqueous humour: The aqueous humour is a transparent, nourishing fluid that fills the gap between the lens and the cornea. It is what gives the eye its round shape.

Anterior ocular segment: The anterior ocular segment is the front portion of the eye, which comprises the cornea, iris, and lens. 

Choroid: The choroid is a high vascularized layer of the eyeball separating the retina and the sclera. 

Cornea: The cornea is the eye’s transparent outer layer, which protects against dirt, germs, and other damaging debris. The cornea also helps focus the light on the retina at the back of the eye.

Iris: The iris is the coloured portion of the eye, which contains the pupil in the centre.

Lens: The lens is situated behind the cornea and pupil. Similarly to a camera lens, an eye lens brings things into focus, making objects appear sharp and clear.

Macula: The macular is in the centre of the retina, and it is what allows the eyes to see clear details and colours.

Optic nerve: Also known as the cranial nerve II, the optic nerve communicates visual information from the retina to the brain. 

Pupil: The pupil is the dark hole at the centre of the iris, which regulates the amount of light that reaches the retina. 

Retina: The retina is a thin layer of tissue at the back of that eye that detects light and transfers images to the brain. 

Scela: The sclera is the white of the eye, which wraps around most of the eyeball, extending from the cornea in the front to the optic nerve in the back. 

Tears: Although tears are often thought of in relation to crying, they are actually essential for keeping the eyes moist and protecting them from irritation and infection. 

Tonometry: Tonometry is an eye test used to measure the pressure levels inside the eyes. It helps to detect glaucoma, along with many other eye diseases. 

Tunnel vision: Tunnel vision is the inability to see objects outside the central field of vision. In other words, it is the loss of peripheral vision. 

Vision therapy: Vision therapy comprises various exercises and treatments to improve visual capacity. 

Eye conditions

Amblyopia: Amblyopia is a condition commonly referred to as a “lazy eye.” It usually appears in childhood and refers to the lack of development of visual systems corresponding to one or both eyes within the brain. This leads to decreased vision in otherwise healthy eyes.

Aphakia: Aphakia is an eye condition caused by a missing lens in one or both eyes. A person can either be born with the condition or it can be triggered by an injury or cataracts surgery.

Asthenopia: Asthenopia is another word for “eyestrain,” caused by fatigue or discomfort. The condition is usually accompanied by headaches, blurry vision and/or sensitivity to light.

Astigmatism: Astigmatism indicates an imperfect curvature of the eye’s cornea, which can cause blurred vision. In the case of an astigmatism, the eye of shaped like an egg rather than a ball.  It’s a very common eye condition and is easily treatable.  

Cataracts: Cataracts are when the eye’s lens becomes cloudy gradually over time, leading to blurry, less robust vision. Cataracts are very commonly associated with aging.

Colour blindness: Also called colour vision deficiency, colour blindness is characterized by the decreased ability to see differences in colour. While it is usually genetic, colour blindness can result from the eye’s colour-sensitive cells not functioning properly. Complete colour blindness is rare, whereas red-green colour deficiency is most common.

Conjunctivitis: Conjunctivitis, otherwise known as pink eye, is an infection of the tissue that lines the inner eyelid and eyeball. Conjunctivitis commonly causes itchiness, redness, and sometimes crusty discharge.

Diabetic retinopathy: Diabetic retinopathy can be a complication of diabetes that directly impacts the eyes. The condition, which typically starts with very mild symptoms (if any), is caused by damage to blood vessels in the retina. 

Myodesopsia: Myodesopsia (otherwise known as floaters) are tiny, dark spots that can float across the field of vision. They usually come and go without requiring treatment, though in some cases the presence of floaters may indicate a severe eye issue.

Glaucoma: Glaucoma is a group of eye diseases that result in damage to the optic nerve, which can result in whole or partial vision loss.

Hyperopia: Commonly called farsightedness, hyperopia is an eye condition in which nearby objects are blurry, while far objects are relatively clear. The eyes must strain to see up close objects, but can focus on things in the distance far more easily.

Myopia: Commonly called nearsightedness, myopia is a common vision condition in which a person without vision correction can see objects close to them clearly, while objects further away are blurry.

Macular degeneration: Macular degeneration is an eye disease that results in the deterioration of the macula, the part of the retina that correlates to the centre of one’s vision. It is commonly associated with aging, and there are two basic types: dry and wet.

- Dry macular degeneration causes reduced central vision and thinning of the macula, and it can develop to become wet macular degeneration.

- Wet macular degeneration is more severe, and is characterized by leaking blood vessels that grow beneath the retina.

Nyctalopia: Also known as night blindness, nyctalopia is the inability to see well in darkness.

Presbyopia: Presbyopia is a condition commonly associated with aging in which the lens inside the eye loses flexibility, causing the eyes to lose their ability to focus on objects close up.

Strabismus: Strabismus, commonly called “crossed eyes,” or “lazy eyes” is a disorder in which only one eye is looking at the target, while the other is looking elsewhere.

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